**Calm Technology for Biofeedback: Why and How?**

**Calm Technology for Biofeedback: Why and How?**

DOI: 10.5772/intechopen.71114

Loe Feijs and Frank Delbressine Loe Feijs and Frank Delbressine Additional information is available at the end of the chapter

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/intechopen.71114

#### **Abstract**

We discuss several possibilities and fundamental difficulties when designing biofeedback systems based on calm technology. As a carrier for the discussion, we develop a novel biofeedback installation based on heart rate variability (HRV). The system is built-in to an elegant table and gives visual feedforward or feedback for relaxation based on breathing. When in feedforward mode, the system will show a sine wave of about 7 cycles per second, close to the well-known resonant breathing frequency. Alternatively, the amplitude of the movement can give feedback on the heart rate variability level, which is known to be directly associated with a reduced level of mental stress. The demonstrator has a pulse-plethysmography sensor which measures the beat-to-beat intervals of successive heart beats. The mechanical design of the actuator is designed to operate completely noiseless. Both the adaptive algorithm and the actuator are new to the best of our knowledge. Still new fundamental questions arise.

**Keywords:** biofeedback, breathing, active surface, data visualization, real-time, calm technology

### **1. Introduction**

There are many relaxation techniques and meditation techniques in which breathing plays an important role. Burn-out and depression are contemporary conditions with high prevalence [1, 2] and there is an increasing evidence that certain types of breathing-based biofeedback are helpful to support therapies [3, 4]. Key notions in these feedback approaches are breathing and heart rate variability (HRV).

The term "calm technology" has been proposed by Weiser and Brown in their first essay in 1995 [5] and it has been very influential in the sense that ambitious research programs have been based on it such as the Ambient Intelligence program described by Aarts and Marzano [6]. As Weiser and Brown argue, "Information technology is more often the enemy of calm. Pagers, cellphones,

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2017 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

newservices, the World-Wide-Web, email, TV, and radio bombard us frenetically". Despite the original enthusiasm for calm technology, we are still bombarded frenetically, by these media, and at the same time by a growing variety of new social media, geographic information systems and large public displays. One would expect that the application domain of biofeedback for relaxation would embrace calm technology but, with a few exceptions, that is not what happened. Instead, different developments can be observed: gamification of biofeedback and the rise of mindfulness as an alternative approach for coping with stress. But the topic of calm biofeedback technology is still studied in Stanford University's Calming Technology Lab [7] and at TU/e. Also, there exist several design proposals where the biofeedback is rendered more ambient, not in a handheld device or a smart phone. Examples are the ExoPranayama system by Moran and others [8] and the Living Surface by Yu in cooperation with Alissa and Nienke [9].

Traditional breathing techniques fall into two categories: (1) breathing in a prescribed rhythm and (2) observing one's own breath mindfully, without any restrictions. Pranayama yoga belongs to the first category, Anapanasati (mindfulness of breathing) to the second. Modern technology-based techniques can be categorized into two somewhat related categories: feedforward systems and feedback systems. Paced breathing software such as EZ-air belongs to the first category, Stress-eraser and Cardio Sense Trainer to the second category. But there are differences between the modern technology-based techniques and the traditional-breathing techniques, based on a new understanding of our internal mechanisms connecting breathing, heart rate (HR) and stress. We mention the following insights [10].


In this article we present and demonstrate a novel biofeedback installation based on heart rate variability. We discuss the design choices, some of the alternatives and some of the fundamental challenges we encountered. Both the information display and the model-based biofeedback software are new to the best of our knowledge. Whereas today's trend is to use the smart phone as the main platform for displaying information, we believe there is a need for a real calm technology, which keeps a distance from the overloaded screen, the multi-functionality and the busy social-media life that are associated with smart phones. Therefore we decided to try turning the biofeedback system into a minimalist modernist furniture element with a novel shape-changing interface as information display. To be in contact again with one's heart and indirectly with one's unconscious emotion regulation system is an important activity which deserves a special place and attention to the biofeedback training ritual. The biofeedback system is designed to support that. We aim at an information display which is a subtly shapechanging interface, which is completely flat at rest, having certain esthetic qualities of its own.

The idea of calmness is also essential to the design of the software implementing the translation from the sensor to the actuator. Existing feedback systems fall into various overlapping categories:


The first category is a rich cocktail of 2–4. But it is certainly not adopted here because it is not calm. On the contrary, it adds to the information overload which is perhaps one of the causes of stress in the first place. The second category (labeled I, for integrating in our 2010 paper [11]) has great potential for being calm or playful, but the integrative nature of the calculation has the effect that the improvements are only apparent after a significant number of heart beats or even after several breaths. The delay between cause and effect is likely to hamper learning. The third and fourth interventions, called proportional (P) and differential (D) in [11], are more immediate, but they are another source of unrest themselves: as each heart beat appears, the pumping irregular rhythm of the heart is visible in a dominant way. Yu tested auditory variations of the fourth category [12] and found that they were difficult to understand and not optimal for relaxation. Of course it is possible to filter the tachogram, smoothing the plot so the individual beats do longer appear. Regretfully, the classical filter techniques unavoidably cause delays of at least several seconds (several beats). This is a fundamental difficulty which we set out to resolve in Section 4. We developed a novel filter which combines smoothing with predictive filtering. Sections 2 (usage scenario) and 3 (shape-changing information display) provide a context for the more technical work in Sections 4 and 5.

### **2. Usage scenario**

newservices, the World-Wide-Web, email, TV, and radio bombard us frenetically". Despite the original enthusiasm for calm technology, we are still bombarded frenetically, by these media, and at the same time by a growing variety of new social media, geographic information systems and large public displays. One would expect that the application domain of biofeedback for relaxation would embrace calm technology but, with a few exceptions, that is not what happened. Instead, different developments can be observed: gamification of biofeedback and the rise of mindfulness as an alternative approach for coping with stress. But the topic of calm biofeedback technology is still studied in Stanford University's Calming Technology Lab [7] and at TU/e. Also, there exist several design proposals where the biofeedback is rendered more ambient, not in a handheld device or a smart phone. Examples are the ExoPranayama system by Moran and

Proceedings of the Conference on Design and Semantics of Form and Movement - Sense and Sensitivity, DeSForM

Traditional breathing techniques fall into two categories: (1) breathing in a prescribed rhythm and (2) observing one's own breath mindfully, without any restrictions. Pranayama yoga belongs to the first category, Anapanasati (mindfulness of breathing) to the second. Modern technology-based techniques can be categorized into two somewhat related categories: feedforward systems and feedback systems. Paced breathing software such as EZ-air belongs to the first category, Stress-eraser and Cardio Sense Trainer to the second category. But there are differences between the modern technology-based techniques and the traditional-breathing techniques, based on a new understanding of our internal mechanisms connecting breathing,

• Heart rate variability (HRV) tends to go up under conditions of relaxation and it goes down under stress. The HRV signal is rich and complicated and can be analyzed in many ways, for example, distinguishing low- and high-frequency components. Visualizing HRV allows performing biofeedback training to reduce stress levels and supports reducing anxiety,

• Breathing in, heart rate goes up, if we breathe out, heart rate goes down. The phenomenon is called respiratory sinus arrhythmia (RSA), and it allows to artificially increase heart rate variability. The effect is most strong at a particular frequency near 0.1 Hz which is called

In this article we present and demonstrate a novel biofeedback installation based on heart rate variability. We discuss the design choices, some of the alternatives and some of the fundamental challenges we encountered. Both the information display and the model-based biofeedback software are new to the best of our knowledge. Whereas today's trend is to use the smart phone as the main platform for displaying information, we believe there is a need for a real calm technology, which keeps a distance from the overloaded screen, the multi-functionality and the busy social-media life that are associated with smart phones. Therefore we decided to try turning the biofeedback system into a minimalist modernist furniture element with a novel shape-changing interface as information display. To be in contact again with one's heart and indirectly with one's unconscious emotion regulation system is an important activity which deserves a special place and attention to the biofeedback training ritual. The biofeedback system is designed to support that. We aim at an information display which is a subtly shapechanging interface, which is completely flat at rest, having certain esthetic qualities of its own.

others [8] and the Living Surface by Yu in cooperation with Alissa and Nienke [9].

heart rate (HR) and stress. We mention the following insights [10].

burnout and depression.

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resonant breathing.

The installation will be in the living room or private library of the user. Next to the dedicated table, which includes the shape-changing information display and the embedded software, there is a comfortable chair. When the user decides to do a relaxation session, she sits in the comfortable chair, attaches the sensor to one finger and relaxes. She watches the shapechanging information display, which is the top of the table, and observes the regular rhythm of the subtly moving surface. Alternatively she can put a hand on the top of the table and feel

the moving surface. She breathes in the very same rhythm indicated by the moving surface. During the first 5 min, that is what she does. It is a relaxing experience. Then the system gradually and automatically moves into feedback mode. The user has to train in a goal-oriented fashion now. The goal is to maximize the amplitude of the movement of the surface. Larger amplitude means higher heart rate variability, which means higher level of relaxation. The system does not provide instructions explicitly, the goal to maximize amplitude is told to the user beforehand when she obtains or buys the system. After a total of 10 or 15 min, the session can be stopped, as the user wishes. The user feels more relaxed and is ready for other daily tasks. The user can do one or two relaxation sessions per day, according to personal preferences or needs.

### **3. Design of a shape-changing information display**

The side table was designed by Sander Lucas and produced in studio LUCAS&LUCAS in Eindhoven. We had asked Lucas to re-use the design language of furniture for the Mind the Step exhibition, which was also designed by Lucas. *Mind the Step* is an annual design and technology exhibit which is part of the Dutch Design Week (DDW). We appreciate the modernist and minimalist form of this furniture. The table is made of wood, painted white, very compatible with the calm design aim. On top is the shape-changing interface: a surface which moves up and down, in accordance with the breath feedforward or feedback. The surface is made of polyoxymethylene (POM), which has high stiffness and low friction. We experimented with polymethylacrylate (PMA) too, but it is too brittle. The plate material is turned into a flexure by laser-cutting. The cut is a double-threaded spiral with a particular pattern with angles of (close to) 90° forming an interlocking tessellation. The basic tiles are connected by thin strips, which give rise to an extremely flexible surface. One sees not only the laser-cut spiral, but also, as a Gestalt, emerging spiral lines like in a pine cone or a pineapple (phyllotaxis). When the surface is flat, the latter spirals are apparent, the cut spiral is harder to see. When the surface deforms from flat to non-flat, the vertical cuts appear very clearly with a subtle and beautiful effect (**Figure 1**).

There is significant freedom in the design of the flexure. The spiral was considered a good solution for the shape-changing surface because it is a kind of labyrinth, the archetype of the journey to one's self. For the tessellation, we adopted a specific fashionable and intriguing pattern, mathematically explored by the first author in earlier studies published in Bridges. The spiral generator is written in Processing, and uses Oogway, a turtle-graphics library designed by Hu in 2013 [13]. Each spiral is written, starting at the inner loop, with the turtle spiraling outward. The outer demarcation line of one basic tile consist of 20 commands forward(s) in turtle graphics, 8 commands left (90) and 9 right (90 + dα). So each right-turning angle has a slight deviation dα and the accumulated effect is that after *T* tiles there is a total deviation of *T* × 9 × dα, which must be 360°. We arbitrarily chose *T* = 21, solving dα = 1.90476190°. After each tile, the basic step-size *s* is increased by a factor 1.0148. So after each full turn, the tessellated tiles are a factor (1.0148)<sup>21</sup> = 1.3614 larger than before. After nine full turns, the outermost tile is (1.3614)9 = 16 times larger than the innermost tile (**Figure 2**).

**Figure 1.** The double-threaded tessellated spiral used for laser-cutting.

the moving surface. She breathes in the very same rhythm indicated by the moving surface. During the first 5 min, that is what she does. It is a relaxing experience. Then the system gradually and automatically moves into feedback mode. The user has to train in a goal-oriented fashion now. The goal is to maximize the amplitude of the movement of the surface. Larger amplitude means higher heart rate variability, which means higher level of relaxation. The system does not provide instructions explicitly, the goal to maximize amplitude is told to the user beforehand when she obtains or buys the system. After a total of 10 or 15 min, the session can be stopped, as the user wishes. The user feels more relaxed and is ready for other daily tasks. The user can do one or two relaxation sessions per day, according to personal prefer-

Proceedings of the Conference on Design and Semantics of Form and Movement - Sense and Sensitivity, DeSForM

The side table was designed by Sander Lucas and produced in studio LUCAS&LUCAS in Eindhoven. We had asked Lucas to re-use the design language of furniture for the Mind the Step exhibition, which was also designed by Lucas. *Mind the Step* is an annual design and technology exhibit which is part of the Dutch Design Week (DDW). We appreciate the modernist and minimalist form of this furniture. The table is made of wood, painted white, very compatible with the calm design aim. On top is the shape-changing interface: a surface which moves up and down, in accordance with the breath feedforward or feedback. The surface is made of polyoxymethylene (POM), which has high stiffness and low friction. We experimented with polymethylacrylate (PMA) too, but it is too brittle. The plate material is turned into a flexure by laser-cutting. The cut is a double-threaded spiral with a particular pattern with angles of (close to) 90° forming an interlocking tessellation. The basic tiles are connected by thin strips, which give rise to an extremely flexible surface. One sees not only the laser-cut spiral, but also, as a Gestalt, emerging spiral lines like in a pine cone or a pineapple (phyllotaxis). When the surface is flat, the latter spirals are apparent, the cut spiral is harder to see. When the surface deforms from flat to non-flat, the vertical cuts appear very clearly with a

There is significant freedom in the design of the flexure. The spiral was considered a good solution for the shape-changing surface because it is a kind of labyrinth, the archetype of the journey to one's self. For the tessellation, we adopted a specific fashionable and intriguing pattern, mathematically explored by the first author in earlier studies published in Bridges. The spiral generator is written in Processing, and uses Oogway, a turtle-graphics library designed by Hu in 2013 [13]. Each spiral is written, starting at the inner loop, with the turtle spiraling outward. The outer demarcation line of one basic tile consist of 20 commands forward(s) in turtle graphics, 8 commands left (90) and 9 right (90 + dα). So each right-turning angle has a slight deviation dα and the accumulated effect is that after *T* tiles there is a total deviation of *T* × 9 × dα, which must be 360°. We arbitrarily chose *T* = 21, solving dα = 1.90476190°. After each tile, the basic step-size *s* is increased by a factor 1.0148. So after each full turn, the tessellated tiles are a factor (1.0148)<sup>21</sup> = 1.3614 larger than before. After nine full turns, the outermost

= 16 times larger than the innermost tile (**Figure 2**).

**3. Design of a shape-changing information display**

ences or needs.

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subtle and beautiful effect (**Figure 1**).

tile is (1.3614)9

We were surprised by the extreme flexibility of the spiral, first cut in a wooden version. Just holding it in our hands, we got the serendipity moment to see that such spiral would be a good solution for the design challenge of a shape-changing interface to be combined with the biofeedback algorithms already under development. We then optimized the design by choosing size, material and more technical elements such as a voice coil to obtain the visible effects for the biofeedback installation. We considered servo-motors but they are noisy and they wear out, so we rejected them and began exploring voice coils. The voice coil is precisely the same as the voice coils used in loudspeakers and a current of 0.5 A is enough to move 5 mm (free) or 3 mm (loaded with the spiral). Although it is very difficult to produce very low

**Figure 2.** The furniture of the biofeedback installation.

frequency soundwaves with voice coils, it is not hard to produce mechanical movement (the difficulty would be in transferring the movement to the free air). To drive the voice coil we developed a simple direct current (DC) amplifier with a LM324 op-amp and an MJE3055 transistor in emitter-follower configuration (traditional audio amplifiers will not work). During further explorations we found that the actuator does not serve well as a haptic actuator, yet the visible effect is precisely what we need. The connection between the voice coil and the spiral went through many rounds of exploration and testing. In the end we found the best solution to be that the spiral is supported by flat surface underneath and is pushed up by the voice coil at one or a few off-center points only. The effect is that the spiral lies completely flat when not in use but works as an information display during feedforward and feedback sessions. In the terminology of Skakoon [14] the surface is flat by force closure where the weight of the spirals acts as the nesting force (in the flat state). We found that the actuator works completely silently (no noticeable voice-coil sounds, no noticeable mechanical friction sounds).

### **4. Design of the smoothing predictive filter**

frequency soundwaves with voice coils, it is not hard to produce mechanical movement (the difficulty would be in transferring the movement to the free air). To drive the voice coil we developed a simple direct current (DC) amplifier with a LM324 op-amp and an MJE3055 transistor in emitter-follower configuration (traditional audio amplifiers will not work). During further explorations we found that the actuator does not serve well as a haptic actuator, yet the visible effect is precisely what we need. The connection between the voice coil and the spiral went through many rounds of exploration and testing. In the end we found the best solution to be that the spiral is supported by flat surface underneath and is pushed up by the voice coil at one or a few off-center points only. The effect is that the spiral lies completely flat when not in use but works as an information display during feedforward and feedback sessions. In the terminology of Skakoon [14] the surface is flat by force closure where the weight of the spirals acts as the nesting force (in the flat state). We found that the actuator works completely

Proceedings of the Conference on Design and Semantics of Form and Movement - Sense and Sensitivity, DeSForM

**Figure 2.** The furniture of the biofeedback installation.

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silently (no noticeable voice-coil sounds, no noticeable mechanical friction sounds).

The main characteristic of the heart signal is that it consists of discrete events appearing at intervals which are slightly irregular. The heart beat events can be detected using a variety of techniques. The most reliable method is by peak detection in the electrocardiogram (ECG), which requires a fairly obtrusive sensor (something with electrodes). Each peak is called an R event (referring to the QRS complex discovered by Einthoven). We used a pulse-plethysmography (PPG) sensor, which works with a small clip on the finger or the ear. PPG is a reasonable compromise between ease of use and reliability. The sensor, amplifier, detection circuit and Arduino interrupt routine are described by Langereis [15]. Note that most smart watches and face color-based camera detector systems can deliver heart rate (HR), but are not yet able to detect each individual beat and hence cannot (yet) reliably calculate beat-to-beat intervals, which is essential for heart rate variability (HRV).

Now we describe why we aim at a novel filter which combines smoothing with predictive filtering. To clarify the fundamental challenge we refer to **Figure 3**. Consider a sequence of heart beats arising at times t(i − 5), t(i − 4), …, t(i − 1), t(i), where i is the index of the last beat detected (a). In a tachogram, the beat-to-beat intervals RR(k) = t(k) – t(k − 1) are plotted vertically against a horizontal time axis, which is a typical way to visualize heart rate variability on a screen (as in stress-eraser). For a shape-changing interface, we could translate them directly into a Voltage V(t) proportional to RR(i) and use that to drive the voice coil during the time interval t(i) < t < t(i + 1). But the heart beats appear as staircases in the tachogram and as jumps in V(t) and hence as jumps by the shape-changing interface (b). It is technically possible to get rid of the staircases by analog or digital filter techniques such as resistor-capacitor filters or finite impulse response (digital) filters, but the filters always introduce a delay. So an increase in RR interval appears in the filtered tachogram or on the voice-coil's Voltage only several beats after the increase happened (c). Even if we would interpolate the vertical plots linearly (d, first four lines), we would still not know what to plot or what Voltage to provide during the interval *after* the last beat, t(i) < t < t(i + 1)? But if we would have a prediction RR\*(t + 1) for RR(t + 1),

**Figure 3.** Heart beats appearing at irregular intervals (a), tachogram with intervals plotted vertically (b), RC-filtered signal (c) and continuous smooth interpolation with predication for last segment (d).

"looking into the future", we could plot a continuous line (d, including dashed line). Next we could explore all kinds of spline techniques or smoothing techniques to eliminate the staircases and triangular forms. Therefore we decided to develop an experimental predictive filter.

Predictive filters are used in areas such as motion detection of cameras or path prediction of airplanes (for military purposes, regretfully). The most used technique is Kalman filtering, which deploys a given dynamic model of the object's behavior (typically based on Newtonian or Lagrangian equations of motion). The time constants and Eigen-frequencies of the dynamic behavior are built-in to the model. In our case, we do not know the breathing frequency beforehand so we need a special model, not precisely Kalman. We work in a transformed RR space where we can estimate the momentary breathing rate, denoted as E(BR). The algorithm is remotely related to the minima and maxima-counting method of Schaefer and Kratky [16], who claim that it allows not only determining average values over the investigated time interval, but also to define an instantaneous respiratory rate. A Fourier transform is not very helpful because that would find a spectrum after many breaths only and cannot adapt quickly (and is not accurate either, as shown by McMullen et al. [17]). Further details of the special model are outside the scope of the present paper. We take the previous RR intervals RR(i), RR(i − 1), RR(i − 2), etc. as inputs, but using exponential weighing (so the very old values do not matter anymore). From RR(i) and RR\*(i + 1) we can find plot values or Voltages for at least one (estimated) interval duration after the last detected beat. We explored Catmull Rom splines, based on the polynomial V(τ) = ½(−τ + 2τ<sup>2</sup> − τ<sup>3</sup> )RR(i − 1) + ½(2 − 5τ<sup>2</sup> + 3τ<sup>3</sup> )RR(i) + ½ (τ + 4τ<sup>2</sup> − 3τ<sup>3</sup> ) RR\*(i + 1) + ½(−τ<sup>2</sup> + τ<sup>3</sup> )RR\*(i + 2) with τ = t − t(i) for t > t(i), which has the advantage that the lines are continuous and their slopes are continuous too. Schaefer and Kratky [16] work with splines as well, yet not for t > t(i). After multiple trial versions we decided for linear interpolation with jump smoothing of slope discontinuities, which we found to be more robust against outliers and poor predictions as shown in **Figure 4**. The filter is realized in software, first developed in Processing (for easy testing) and then ported to Arduino as an embedded system within the installation. The system has no buttons, remote control or data collection options, in accordance with the design goal to create calm technology. Plugged into the mains, it works.

There are several alternative options for extracting meaningful data from the sensor data. We could work with mixed linear models (good in case of missing data) or machine learning

**Figure 4.** Overview of predictive and smoothing system.

(taking advantage of large data sets). We should also mention that we see new technologies at the horizon for getting the heart beat or respiratory data even better, that is, less intrusively. Ballistocardiographic or face image-based methods (vascular mapping, blood perfusion modeling) could allow us to get rid of the PPG sensor.

### **5. Mechanical design of the actuator**

"looking into the future", we could plot a continuous line (d, including dashed line). Next we could explore all kinds of spline techniques or smoothing techniques to eliminate the staircases and triangular forms. Therefore we decided to develop an experimental predictive filter. Predictive filters are used in areas such as motion detection of cameras or path prediction of airplanes (for military purposes, regretfully). The most used technique is Kalman filtering, which deploys a given dynamic model of the object's behavior (typically based on Newtonian or Lagrangian equations of motion). The time constants and Eigen-frequencies of the dynamic behavior are built-in to the model. In our case, we do not know the breathing frequency beforehand so we need a special model, not precisely Kalman. We work in a transformed RR space where we can estimate the momentary breathing rate, denoted as E(BR). The algorithm is remotely related to the minima and maxima-counting method of Schaefer and Kratky [16], who claim that it allows not only determining average values over the investigated time interval, but also to define an instantaneous respiratory rate. A Fourier transform is not very helpful because that would find a spectrum after many breaths only and cannot adapt quickly (and is not accurate either, as shown by McMullen et al. [17]). Further details of the special model are outside the scope of the present paper. We take the previous RR intervals RR(i), RR(i − 1), RR(i − 2), etc. as inputs, but using exponential weighing (so the very old values do not matter anymore). From RR(i) and RR\*(i + 1) we can find plot values or Voltages for at least one (estimated) interval duration after the last detected beat. We explored Catmull Rom splines,

Proceedings of the Conference on Design and Semantics of Form and Movement - Sense and Sensitivity, DeSForM

− τ<sup>3</sup>

lines are continuous and their slopes are continuous too. Schaefer and Kratky [16] work with splines as well, yet not for t > t(i). After multiple trial versions we decided for linear interpolation with jump smoothing of slope discontinuities, which we found to be more robust against outliers and poor predictions as shown in **Figure 4**. The filter is realized in software, first developed in Processing (for easy testing) and then ported to Arduino as an embedded system within the installation. The system has no buttons, remote control or data collection options, in accordance with the design goal to create calm technology. Plugged into the mains, it works. There are several alternative options for extracting meaningful data from the sensor data. We could work with mixed linear models (good in case of missing data) or machine learning

)RR(i − 1) + ½(2 − 5τ<sup>2</sup>

)RR\*(i + 2) with τ = t − t(i) for t > t(i), which has the advantage that the

+ 3τ<sup>3</sup>

)RR(i) + ½ (τ + 4τ<sup>2</sup>

 − 3τ<sup>3</sup> )

based on the polynomial V(τ) = ½(−τ + 2τ<sup>2</sup>

**Figure 4.** Overview of predictive and smoothing system.

+ τ<sup>3</sup>

RR\*(i + 1) + ½(−τ<sup>2</sup>

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The mechanical design of the actuator is designed to operate completely noiseless. Although specific users might like the sound of servo-motors [8], the requirement of calm design suggests that it is much better to keep the mechanism silent. A voice coil meets this requirement very well. Although this is the very same mechanism used in loudspeakers to generate high volume sound, a voice coil can operate silently at very low frequencies—as in this design. The basic idea of the mechanism is described in **Figure 5**. At present there are two driving pins, but it could be any other number. The force of gravity makes sure that the spiral flexure lays completely flat, except at certain positions where a driving pin pushes it upward. The force of gravity works as a nesting force [14], yet when the driving pin is low, the spiral flexure cannot sink into the (circular) holes.

**Figure 5.** Mechanical design of the actuator (1: moving voice coil, 2: air gap, 3: magnet, 4: steel flux return, 5: driving pin, 6: horizontal support plate with holes, 7: support structure, 8: spiral flexure).

### **6. Conclusions and outlook**

The system can work both in feedforward mode and in feedback mode. When in feedforward mode, the system will show a sine wave of about 7 cycles per second, close to the well-known resonant breathing frequency [10]. This is an easy way for the user to get started. Then after

5 min, the system gradually goes into feedback mode. When the deep and regular breathing continues, the system will respond with movements which are of the same frequency and approximate phase as the user's breathing. In this state, the distinction between feedback and feedforward has disappeared (with respect to frequency). User and system are synchronized. The amplitude of the actuator's movement still provides feedback on HRV amplitude.

As a limitation we mention that the present set-up is not yet comfortable enough for sessions longer than 10 or 20 min. However, for relaxation that should be enough (typical audio tapes of progressive muscle relaxation are also not longer than 10 min).

The design goal of creating calm technology has been met in several ways. We found that for the form-giving, and the display the aim of "calm" can be implemented satisfactorily: the chosen hounds-tooth labyrinth is just one of many possibilities for the flexure pattern; the voice coil works silently. The PPG sensor is not very comfortable, but we leave it for now (in a few years, camera-based pulse detection technology could be available). The interaction by breathing works well in feedforward mode and also in feedback mode when breathing is regular indeed. Still there is a lot of work to be done as we found that irregular breathing breaks the synchronization, and we are still exploring options to provide useful feedback in such conditions. We also found an open question regarding HRV: how to interpret the HRV components which are *not* caused by RSA? If breathing is shallow and other, non-breath HRV components dominate, the combined smoothing and predictive filtering algorithm does not work well. In a different setting McMullen et al. [17] discuss how RSA peak frequency and breathing frequency do not coincide. We do not know what precisely causes the nonbreathing-related HRV component? Does it allow one-beat ahead prediction? How does it correlate to thoughts or absence thereof? There is literature on the various sources of vagal cardiac control, but so far we got lost in literature, which is either on vagal control brain nuclei studied in rats, or on statistical long-term HRV parameters—which are not helpful for shortterm prediction. We leave the matter as an (extremely interesting) option for future research.

Finally let us mention how to conduct experiments for fine-tuning the feedforward and feedback subsystems. The formal evaluation of the feedforward could be done along the lines of Yu's research who has been testing soundscapes and their effect on subjective and objective relaxation [18]: for subjective relaxation there exist instruments such as the Relaxation Rating Scale (RSS). An alternative is the State-Trait Anxiety Inventory (STAI). These can be combined with open interviews. Objective relaxation can be assessed using HRV. For testing the feedback subsystem it would make sense to benchmark the breathing extraction algorithm against other ways of deriving the respiratory influences on the HRV, for example, using so-called Orthogonal Subspace Projection (OSP) [19]. We leave these as options for future research.

### **Acknowledgements**

We like to thank Sander Lucas, Jeanette Schoumacher, Sabine Van Huffel, Biyong Zhang, Matthias Rauterberg, Geert van den Boomen, Jasper Sterk and Chet Bangaru for their kind help and support during the development of this project.

### **Author details**

5 min, the system gradually goes into feedback mode. When the deep and regular breathing continues, the system will respond with movements which are of the same frequency and approximate phase as the user's breathing. In this state, the distinction between feedback and feedforward has disappeared (with respect to frequency). User and system are synchronized.

Proceedings of the Conference on Design and Semantics of Form and Movement - Sense and Sensitivity, DeSForM

As a limitation we mention that the present set-up is not yet comfortable enough for sessions longer than 10 or 20 min. However, for relaxation that should be enough (typical audio tapes

The design goal of creating calm technology has been met in several ways. We found that for the form-giving, and the display the aim of "calm" can be implemented satisfactorily: the chosen hounds-tooth labyrinth is just one of many possibilities for the flexure pattern; the voice coil works silently. The PPG sensor is not very comfortable, but we leave it for now (in a few years, camera-based pulse detection technology could be available). The interaction by breathing works well in feedforward mode and also in feedback mode when breathing is regular indeed. Still there is a lot of work to be done as we found that irregular breathing breaks the synchronization, and we are still exploring options to provide useful feedback in such conditions. We also found an open question regarding HRV: how to interpret the HRV components which are *not* caused by RSA? If breathing is shallow and other, non-breath HRV components dominate, the combined smoothing and predictive filtering algorithm does not work well. In a different setting McMullen et al. [17] discuss how RSA peak frequency and breathing frequency do not coincide. We do not know what precisely causes the nonbreathing-related HRV component? Does it allow one-beat ahead prediction? How does it correlate to thoughts or absence thereof? There is literature on the various sources of vagal cardiac control, but so far we got lost in literature, which is either on vagal control brain nuclei studied in rats, or on statistical long-term HRV parameters—which are not helpful for shortterm prediction. We leave the matter as an (extremely interesting) option for future research. Finally let us mention how to conduct experiments for fine-tuning the feedforward and feedback subsystems. The formal evaluation of the feedforward could be done along the lines of Yu's research who has been testing soundscapes and their effect on subjective and objective relaxation [18]: for subjective relaxation there exist instruments such as the Relaxation Rating Scale (RSS). An alternative is the State-Trait Anxiety Inventory (STAI). These can be combined with open interviews. Objective relaxation can be assessed using HRV. For testing the feedback subsystem it would make sense to benchmark the breathing extraction algorithm against other ways of deriving the respiratory influences on the HRV, for example, using so-called Orthogonal Subspace Projection (OSP) [19]. We leave these as options for future research.

We like to thank Sander Lucas, Jeanette Schoumacher, Sabine Van Huffel, Biyong Zhang, Matthias Rauterberg, Geert van den Boomen, Jasper Sterk and Chet Bangaru for their kind

The amplitude of the actuator's movement still provides feedback on HRV amplitude.

of progressive muscle relaxation are also not longer than 10 min).

**Acknowledgements**

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help and support during the development of this project.

Loe Feijs\* and Frank Delbressine

\*Address all correspondence to: l.m.g.feijs@tue.nl

Department of Industrial Design, Eindhoven University of Technology, Eindhoven, The Netherlands

### **References**

	- [10] Lehrer PM, Gevirtz R. Heart rate variability biofeedback: How and why does it work? Frontiers in Psychology. 2014;**5**:756
	- [11] Feijs L, Langereis G, Van Boxtel G. Designing for heart rate and breathing movements. In: Proceedings 6th International of the Workshop on DeSForM. Eindhoven: Koninklijke Philips Electronics; 2010. pp. 57-67
	- [12] Yu B, et al. Designing auditory display of heart rate variability I biofeedback context. In: 21st International Conference on Auditory Display (ICAD2015), 6-10 July 2015. Austria: Graz; 2015
	- [13] Feijs L, Hu J. Turtles for tessellations. In: Hart G,Sarhangi R, editors. Proceedings of Bridges 2013: Mathematics, Music, Art, Architecture, Culture. pp. 241-248
	- [14] Skakoon JG. The Elements of Mechanical Design. New York: ASME; 2008
	- [15] Langereis G. PhotoPlethysmoGraphy (PPG), what is PhotoPlethysmography? http:// www.fontyssensorwiki.nl/doku.php?id=methods:ppg:ppg\_main [Accessed: December 2016]
	- [16] Schaefer A, Kratky KW. Estimation of breathing rate from respiratory sinus arrhythmia: Comparison of various methods. Annals of Biomedical Engineering. 2008;**36**(3):476-485
	- [17] McMullen MK, Whitehouse JM, Shine G, Towell A. Respiratory and non-respiratory sinus arrhythmia: Implications for heart rate variability. Journal of Clinical Monitoring and Computing. 2012;**26**(1):21-28
	- [18] Yu B, Hu J, Funk M, Feijs L. A study on user acceptance of different auditory content for relaxation. In: AM '16 Proceedings of the Audio Mostly, Norrköping, Sweden. ACM; 2016. pp. 69-76
	- [19] Widjaja D, Caicedo A, Vlemincx E, Diest IV, Huffel SV. Separation of respiratory influences from the Tachogram: A methodological evaluation. PLoS One. 2014;**9**(7):

**Provisional chapter**

### **Toward the Development of a Monitoring and Feedback System for Predicting Poor Adjustment to Grief Feedback System for Predicting Poor Adjustment to Grief**

**Toward the Development of a Monitoring and** 

DOI: 10.5772/intechopen.71109

Wan Jou She, Laurie Burke, Robert A. Neimyer, Kailey Roberts, Wendy Lichtenthal, Jun Hu and Matthias Rauterberg Kailey Roberts, Wendy Lichtenthal, Jun Hu and Matthias Rauterberg Additional information is available at the end of the chapter

Wan Jou She, Laurie Burke, Robert A. Neimyer,

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/intechopen.71109

#### **Abstract**

[10] Lehrer PM, Gevirtz R. Heart rate variability biofeedback: How and why does it work?

Proceedings of the Conference on Design and Semantics of Form and Movement - Sense and Sensitivity, DeSForM

[11] Feijs L, Langereis G, Van Boxtel G. Designing for heart rate and breathing movements. In: Proceedings 6th International of the Workshop on DeSForM. Eindhoven: Koninklijke

[12] Yu B, et al. Designing auditory display of heart rate variability I biofeedback context. In: 21st International Conference on Auditory Display (ICAD2015), 6-10 July 2015. Austria:

[13] Feijs L, Hu J. Turtles for tessellations. In: Hart G,Sarhangi R, editors. Proceedings of

[15] Langereis G. PhotoPlethysmoGraphy (PPG), what is PhotoPlethysmography? http:// www.fontyssensorwiki.nl/doku.php?id=methods:ppg:ppg\_main [Accessed: December

[16] Schaefer A, Kratky KW. Estimation of breathing rate from respiratory sinus arrhythmia: Comparison of various methods. Annals of Biomedical Engineering. 2008;**36**(3):476-485

[17] McMullen MK, Whitehouse JM, Shine G, Towell A. Respiratory and non-respiratory sinus arrhythmia: Implications for heart rate variability. Journal of Clinical Monitoring

[18] Yu B, Hu J, Funk M, Feijs L. A study on user acceptance of different auditory content for relaxation. In: AM '16 Proceedings of the Audio Mostly, Norrköping, Sweden. ACM;

[19] Widjaja D, Caicedo A, Vlemincx E, Diest IV, Huffel SV. Separation of respiratory influences from the Tachogram: A methodological evaluation. PLoS One. 2014;**9**(7):

Bridges 2013: Mathematics, Music, Art, Architecture, Culture. pp. 241-248

[14] Skakoon JG. The Elements of Mechanical Design. New York: ASME; 2008

Frontiers in Psychology. 2014;**5**:756

Philips Electronics; 2010. pp. 57-67

and Computing. 2012;**26**(1):21-28

Graz; 2015

2017

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2016]

2016. pp. 69-76

Losing a loved one is a fundamental and ubiquitous life experience that is often characterized by a certain period of grief and emotional distress. Although the majority of the bereaved can cope with grief resiliently, around 1 of 10 individuals could experience an unusually protracted and intense response referred to as prolonged grief disorder (PGD) following death of a loved one. PGD is associated with work and social impairment and heightened risk of severe medical and psychological conditions. Current means of diagnosis requires a minimum of 6 months to confirm and identify PGD and is discrepant with the fact that the bereaved may need psychotherapeutic intervention in a more timely manner. Contemporary studies have outlined prospective risk factors that could cause poor bereavement outcome, which can potentially contribute to early identification and prevention of problematic response to grief. Self-monitoring applications have been developed and broadly implemented in a vast spectrum of mental and health-related interventions and self-managing processes. This study presents the conceptualization and development of an Internet-based screening method designed by the researchers and psychotherapists that aims to provide meaningful and quantitative feedback in the early phase of the grief and to support decision making in the bereavement process through monitoring the susceptibility to problematic grief outcome.

**Keywords:** bereavement, prolonged grief disorder, self-monitoring system, Internet-based bereavement support

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2017 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

### **1. Introduction**

Self-management is often considered one of the critical factors that contribute to promoting a better medical or mental health care outcome [1–8]. Applications specifically designed for this purpose are widely implemented in a spectrum of medical and psychological conditions ranging from self-exam of blood pressure and heart rate through screening methods to identify depressive symptoms or assess the level of posttraumatic stress. Users of self-managing applications are not only more informed about their health-related conditions but also more empowered to act as an active role in the health care processes [9, 10]. In 2015, the Wall Street Journal pointed out the frequent implementation and the explicit benefits of self-managing applications in certain medical practices such as cardiovascular rehabilitation program and cancer pain management [11]. The advantage of utilizing self-managing applications in the medical and psychological care procedures is that these applications are more accessible and integrated to users' everyday life experiences. They are often characterized by low cost, connectivity, anonymity, nonstop availability, and opportunities for a self-paced health care approach. For health care service providers, the versatile data gathered or reported from the applications facilitate better monitoring of the users' health-related behaviors and are informative to further studies of the health conditions when compared and analyzed with data from a large group of users.

In the context of bereavement, studies as early as in 2004 have demonstrated that more than half of the bereaved used online bereavement support, and such resources yield potential in preventing and protecting the bereaved from further mental disorders [12–14]. However, as Krysinska and Andriessen warned in one of their papers, most of the websites created by professional bereavement organizations are not immediately available or credited from the search, rendering the quality of online bereavement support and the authenticity of information under question [15].

Accordingly, this article takes a focus on designing a self-management application in bereavement-related contexts and presents the conceptualization and development procedures of it. We start by introducing the context of usage, followed by the process of conceptualizing two approaches to attend the needs in bereavement context. These two approaches were further prototyped into two applications, and one of which was selected for further development and evaluation. In the end, this paper reports a preliminary evaluation of the selected application and elaborates its potential to serve as both a data collection instrument in the future studies and a self-monitoring system for the bereavement process.

### **2. Context of usage-bereavement**

Bereavement refers to an individual's adaptive process following the loss of a loved one through death. The process is characterized by a variety of emotional responses (e.g., grief and distress) and cognitive crisis (e.g., meaning reconstruction), as well as heightened risk of syndromal medical conditioning and social and occupational impairment. It is also a fundamental and life-changing event that almost everyone will encounter in his or her lifetime. The prevalence and ubiquity of loss and grief are reflected in studies showing that most individuals will have experienced at least one loss by early adulthood (e.g., 60% have lost a friend; 81% have lost an extended family member; Herberman et al., 2013). Losing a loved one through death is frequently reported as one of the most stressful life events and was formally rated as the most stressful event in the Holmes and Rahe Stress Scale.

**1. Introduction**

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from a large group of users.

tion under question [15].

Self-management is often considered one of the critical factors that contribute to promoting a better medical or mental health care outcome [1–8]. Applications specifically designed for this purpose are widely implemented in a spectrum of medical and psychological conditions ranging from self-exam of blood pressure and heart rate through screening methods to identify depressive symptoms or assess the level of posttraumatic stress. Users of self-managing applications are not only more informed about their health-related conditions but also more empowered to act as an active role in the health care processes [9, 10]. In 2015, the Wall Street Journal pointed out the frequent implementation and the explicit benefits of self-managing applications in certain medical practices such as cardiovascular rehabilitation program and cancer pain management [11]. The advantage of utilizing self-managing applications in the medical and psychological care procedures is that these applications are more accessible and integrated to users' everyday life experiences. They are often characterized by low cost, connectivity, anonymity, nonstop availability, and opportunities for a self-paced health care approach. For health care service providers, the versatile data gathered or reported from the applications facilitate better monitoring of the users' health-related behaviors and are informative to further studies of the health conditions when compared and analyzed with data

Proceedings of the Conference on Design and Semantics of Form and Movement - Sense and Sensitivity, DeSForM

In the context of bereavement, studies as early as in 2004 have demonstrated that more than half of the bereaved used online bereavement support, and such resources yield potential in preventing and protecting the bereaved from further mental disorders [12–14]. However, as Krysinska and Andriessen warned in one of their papers, most of the websites created by professional bereavement organizations are not immediately available or credited from the search, rendering the quality of online bereavement support and the authenticity of informa-

Accordingly, this article takes a focus on designing a self-management application in bereavement-related contexts and presents the conceptualization and development procedures of it. We start by introducing the context of usage, followed by the process of conceptualizing two approaches to attend the needs in bereavement context. These two approaches were further prototyped into two applications, and one of which was selected for further development and evaluation. In the end, this paper reports a preliminary evaluation of the selected application and elaborates its potential to serve as both a data collection instrument in the future studies

Bereavement refers to an individual's adaptive process following the loss of a loved one through death. The process is characterized by a variety of emotional responses (e.g., grief and distress) and cognitive crisis (e.g., meaning reconstruction), as well as heightened risk of syndromal medical conditioning and social and occupational impairment. It is also a fundamental

and a self-monitoring system for the bereavement process.

**2. Context of usage-bereavement**

Looking from the other side of bereavement, it is a natural mechanism that helps individuals to gradually come to terms with the potentially overwhelming loss and to continue living a productive life in which the deceased is recognized in a different form of existence. The majority of bereaved coped with grief resiliently, and some of them even adopted so well that they further experienced enhanced meaning and spirituality post loss. However, a noteworthy percentage of bereaved, around 1 of 10 bereaved individuals, could experience a protracted and intense response to their grief referred to as prolonged grief disorder (PGD) [16].

Individuals who suffer from PGD often feel "stuck" in the process of bereavement and find it hard to accommodate to a different lifestyle or the world without the deceased. PGD can severely hamper an individual's psychological well-being, as well as the social functioning and physical health. In the extreme situation, individuals could experience strong suicidal tendency. For the individuals who suffer from PGD, psychotherapeutic intervention is mostly needed to support their adaptation and acceptance of the loss. On the other hand, performing grief counseling and therapy to normal grievers could yield deleterious effect and even disturb the natural bereavement procedure.

Since offering grief counseling to normal grievers is unwarranted, a screening method that helps to determine who will benefit from the psychotherapeutic intervention is of the primary importance. Psychologists have outlined the importance and pressing need of a trustworthy screening method, whereas the current PGD diagnosis instruments require a minimum 6 months to identify the PGD symptoms. The amount of time required to issue a PGD diagnosis and to allow psychotherapists' active involvement is discrepant with the fact that individuals who suffer from intense grief or suicidality may need psychotherapeutic intervention in a more timely manner.

The inability to identify potential PGD grievers in an earlier phase could also posit a negative implication on the development of preventive intervention and enhance the difficulty of attending the disorder after 6 months have elapsed. It could potentially explain why studies related to preventing PGD remained scarce and the effect far from warranted.

### **3. Two approaches to predict PGD symptoms in early phase**

Assessing symptomatology and attending to the needs of grievers with severe emotional distress as quickly as possible is imperative. Various approaches were explored by previous bereavement-related studies to identify problematic self-evaluations and potentially traumatic characteristics that contribute to predicting poor adjustment outcomes to bereavement. These approaches can be briefly categorized into two groups.

The first group stems from the problematic narratives and coping strategies can potentially be detected through linguistic cues or behaviors post loss [17–20]. Examples of the first approach include negative self-evaluation such as thinking that the self is less worthy without the deceased and problematic coping strategies such as repetitive rumination of the deceased. The second group evaluates the traumatic loss circumstances and psychological states that can make the bereaved vulnerable to poor adaptation, all of which are often static at the time of loss and are harder to change [21–29]. Examples of the second approach range from traumatic death, lacking social support to the strong dependency on the deceased and an insecure attachment style.

Both approaches are informative for follow-up development of screening methods that could support grievers and psychotherapists to monitor the bereaved's susceptibility to PGD and to target the appropriate interventions in a more timely manner. A primary concern is that these methods remain in a highly theoretical and explorative phase and are in demand of empirical validation. In this regard, the applications developed should also serve as a means of evaluating and validating the proposed screening approaches. With this concept in mind, we propose two Internet-based applications that seek to empower the bereaved by providing meaningful feedback to the aspects related to their grief experiences and, on the other hand, collect useful data that contribute to further validation of the screening methods.

### **4. Method**

#### **4.1. The design and conceptualization of two prototypes of PGD screening methods**

Two prototypes were developed using different approaches. The first prototype, My Grief Journal, was a technology-driven concept based on the available technological solutions and studying the related bereavement literature. The second prototype, Grief Inquiry Following Trauma, was developed with field experts and psychotherapists. The overall aim of both applications is to empower the users to gain knowledge and control of their bereavementrelated decisions. To achieve this goal, the research team defined the following concepts that should be achieved by both prototypes:


• The prototypes should attempt to integrate and utilize the existing and validated measures as a starting point but should remain flexible for developing and validating new measures.

#### **4.2. External experts from the psychological field**

Although the purpose of this project was not to develop an intervention of PCBD, due to the sensitive nature of loss and grief study, the team included one researcher specified on bereavement and post-loss meaning reconstruction and one psychotherapist specified on grief counseling. The external experts brought contribution to the design and phrasing of questions that were used in assessing the grievers' grief experiences and provided further opinions from psychological field on the ethics and design of the study. The author, as a lead investigator of this study, first proposed two prototype concepts based on previous literature review for evaluation within the team, and the final decision was made based on the practicality of the concept and the available technology that could facilitate the prototyping of the app.

Based on the suggestion of the IRB, to pilot test the app and gain users feedback from the concept, the team had recruited a certified thanatologist and grief counselor to facilitate the session. It was meant to avoid bias in interviewing the users and to maintain anonymity of the study. An interview protocol was drafted by the researcher and the psychotherapist to ensure the questions would not provoke excessive/harmful emotional responses. The interview was conducted in English, and all of the users were native English speakers.

#### **4.3. My Grief Journal**

The first group stems from the problematic narratives and coping strategies can potentially be detected through linguistic cues or behaviors post loss [17–20]. Examples of the first approach include negative self-evaluation such as thinking that the self is less worthy without the deceased and problematic coping strategies such as repetitive rumination of the deceased. The second group evaluates the traumatic loss circumstances and psychological states that can make the bereaved vulnerable to poor adaptation, all of which are often static at the time of loss and are harder to change [21–29]. Examples of the second approach range from traumatic death, lacking social support to the strong dependency on the deceased and an insecure attachment style. Both approaches are informative for follow-up development of screening methods that could support grievers and psychotherapists to monitor the bereaved's susceptibility to PGD and to target the appropriate interventions in a more timely manner. A primary concern is that these methods remain in a highly theoretical and explorative phase and are in demand of empirical validation. In this regard, the applications developed should also serve as a means of evaluating and validating the proposed screening approaches. With this concept in mind, we propose two Internet-based applications that seek to empower the bereaved by providing meaningful feedback to the aspects related to their grief experiences and, on the other hand,

Proceedings of the Conference on Design and Semantics of Form and Movement - Sense and Sensitivity, DeSForM

collect useful data that contribute to further validation of the screening methods.

**4.1. The design and conceptualization of two prototypes of PGD screening methods**

Two prototypes were developed using different approaches. The first prototype, My Grief Journal, was a technology-driven concept based on the available technological solutions and studying the related bereavement literature. The second prototype, Grief Inquiry Following Trauma, was developed with field experts and psychotherapists. The overall aim of both applications is to empower the users to gain knowledge and control of their bereavementrelated decisions. To achieve this goal, the research team defined the following concepts that

• Target users: individuals who have experienced death of a loved one and would be interested in searching for support on the Internet, especially individuals who have experienced

• Deliverables: an Internet-based Product Service System (PSS) that provides meaningful, objective, trustworthy, and quantitative feedback of the various bereavement-related aspects.

• Portal: the application should be affordable, easy-to-use, and widely accessible through the

• The system must collect only bereavement-related data from the users and generate per-

• The feedback provided to the users must contain both positive and negative aspects of their

**4. Method**

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should be achieved by both prototypes:

computer and mobile devices.

the loss very recently or less than 6 months ago.

sonalized feedback based on the data collected.

grief situation and must come from the authentic sources.

The concept of My Grief Journal was inspired by studies concerning the self-narratives in the bereavement process and the meaning reconstruction theory. Narrative variables can be effective predictors of psychological health during bereavement and even of the outcome of coping with bereavement. Counting the relevant words in the written text was considered an effective approach to measuring the cognitive changes and emotional expression in the bereavement context. Many suggested endorsed that verbal materials carry more additional information about psychological phenomena and symptoms, which are often less detectable from self-report [19, 30]. For instance, consider the following two examples, "it's so hard to say good bye" and "I am lucky to have somebody that makes saying goodbye so hard." Both sentences included a negative statement but were framed in a different manner and hence reflected different appraisal to an event.

The researchers tested various available types of software and APIs to perform the keywords extraction and analysis and determine the positive emotions and negative emotions in the narratives. We used a narrative that described feelings in an indirect manner. For instance, "I am feeling terribly good today," or "…determined to enjoy her luxury of grief uncomforted." It was easy for human to understand but hard for programs to determine whether the sentence really described a positive perception or a negative one. The most precise software appeared to be Linguistic Inquiry and Word Count (LIWC). However, it was not available in command line interface (CLI) and the EULA prevented users from implementing it in a customized application. Other alternatives tested were NLTK in python, Afinn, and AlchemyAPI. In the end, IBM Alchemy API was implemented to extract meta-data such as concepts, entities, keywords, categories, sentiment, emotion, relations, and semantic roles. Unfortunately, there

was no corpus specifically trained for bereavement-related sentences or articles. Therefore, it could not be as precise as the corpus for movie reviews, tweets, or advertisement.

My Grief Journal was developed to store users' short articles (e.g., diaries) and analyze the sentiment of the article. The analysis will yield two types of results, providing a visualized feedback of the frequency of the emotional keywords detected in the article and determining the positive or negative valence of the keyword and its relationship to five types of emotions (anger, disgust, fear, joy and sadness). **Figures 1** and **2** showed the sample page and report of My Grief Journal. Unfortunately so far, there was no available corpus specifically trained for bereavement-related sentences or articles. Therefore, it could not be as precise as the corpus for movie reviews, tweets, or advertisement, which was an obvious drawback that obstructs the researchers from testing it with grievers. Only the developers and the research team members tested it. Developing My Grief Journal should include training the corpus with plenty of bereavement-related articles or sentences in order to determine how to precisely analyze the sentiment in the users' writing.

#### **4.4. Grief Inquiry Following Trauma (GIFT)**

The concept of GIFT stemmed from psychological studies related to prospective risk factors that could render grievers more vulnerable to PGD, such as low social support, low income, or traumatic death circumstances. A framework of risk factors was created based on literature review (see **Table 1**).


**Figure 1.** The entry page of My Grief Journal.

Toward the Development of a Monitoring and Feedback System for Predicting Poor Adjustment… http://dx.doi.org/10.5772/intechopen.71109 31

**Figure 2.** The demo visualization of keywords and the valence of the keywords.

was no corpus specifically trained for bereavement-related sentences or articles. Therefore, it

Proceedings of the Conference on Design and Semantics of Form and Movement - Sense and Sensitivity, DeSForM

My Grief Journal was developed to store users' short articles (e.g., diaries) and analyze the sentiment of the article. The analysis will yield two types of results, providing a visualized feedback of the frequency of the emotional keywords detected in the article and determining the positive or negative valence of the keyword and its relationship to five types of emotions (anger, disgust, fear, joy and sadness). **Figures 1** and **2** showed the sample page and report of My Grief Journal. Unfortunately so far, there was no available corpus specifically trained for bereavement-related sentences or articles. Therefore, it could not be as precise as the corpus for movie reviews, tweets, or advertisement, which was an obvious drawback that obstructs the researchers from testing it with grievers. Only the developers and the research team members tested it. Developing My Grief Journal should include training the corpus with plenty of bereavement-related articles or sentences in order to determine how to precisely analyze the sentiment in the users' writing.

The concept of GIFT stemmed from psychological studies related to prospective risk factors that could render grievers more vulnerable to PGD, such as low social support, low income, or traumatic death circumstances. A framework of risk factors was created based on literature

could not be as precise as the corpus for movie reviews, tweets, or advertisement.

**4.4. Grief Inquiry Following Trauma (GIFT)**

review (see **Table 1**).

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**Figure 1.** The entry page of My Grief Journal.

All of the risk factors were reviewed by the researcher and the external experts [21, 24]. Two measurement tools were designed together by the researcher and the external experts in order to measure the risk factors. The team has further included another to-be-validated scale for identifying risk factors related to bereavement and loss circumstances. These three questionnaires were grouped into the major section, Basic Information. Basic Information consisted of questionnaires related to the participant's demographic characteristics and proposed predictors of bereavement distress (**Table 1**; scales #1–3). Six validated questionnaires were selected to provide feedback on bereavement-related perspectives. They measured respectively grief degree (PG-13), depression (CESD-R), post-traumatic stress disorder (PCL), resilience (CD-RISC-10), meaning making (ISLES-SF), post-traumatic growth (PTGI). These six questionnaires belonged to the secondary section named Monitor My Grief. **Table 2** displayed a list of scales included in the application. The validated scales administered were, if not openly available, all requested or purchased from the respective researchers and consent acquired to use in the app.

The feedback that addressed the participants' result after taking the questionnaire was drafted for the six validated questionnaires in the Monitor My Grief section. Users who successfully completed the questionnaire will be presented a personalized feedback according to the score of each validated questionnaire. It was meant to adhere to the purpose of design of GIFT and to lessen participants' stress after taking the emotionally disruptive questionnaires.


**Table 1.** Risk factors suggested in the review papers.


Scales #1–3 assess bereavement-related risk factors. Scales #4–9 have been empirically validated and are widely used in bereavement research.

**Table 2.** Assessment instruments.

Personalize the questionnaire with the name of the deceased. An important feature for GIFT was that all of the questions were personalized with the name and gender of the deceased (replace "the deceased" or "the person I lost" into the name of the deceased) to engage the users.

Slider selection for Likert scale questions. Most of the Likert scale options were displayed in a horizontal slider to enhance the linear relationship of the options (see **Figure 6** for an example). The handle will change color after an answer has been indicated (see **Figure 7** for an example). When users access GIFT on a mobile, we choose to keep the two items in the left and right of a Likert scale question but allow users to review the default value after hovering or clicking on the pip on the slider (see **Figure 8**).

Add the option "not applicable" to the risk factor questionnaires. For scale #2 and scale #3, users were provided "not applicable" on the right of all of the questions. This was to allow them to better express themselves when the presented risk circumstances appeared not applicable to them and the options failed to help them to convey it (see **Figure 9**).

According to the IRB suggestion, the website was certified by SSL protocol protection, and all of the data collected in GIFT were coded and encrypted in order to ensure the security of the data.

#### *4.4.1. Preliminary evaluation of GIFT*

**Scale set Scale name To assess**

(CGRF)

Income level Potential Insufficient income

Anticipation of grief Potential Death is unexpected

Prior losses Potential Prior losses

**Table 1.** Risk factors suggested in the review papers.

BRISQ-B)

2. Complicated grief risk factors checklist

**Details**

Proceedings of the Conference on Design and Semantics of Form and Movement - Sense and Sensitivity, DeSForM

Social support level Primary Lacking social support is a salient risk factor that is highly related to problematic grief Discovering the body Primary Discovering the body or viewing the death scene (especially with

Primary Dissatisfaction with death notification

Gender Potential Female grievers are more susceptible to PGD than male grievers

Ethnicity Potential Being non-Caucasian is regarded as a risk factor for PGD Educational level Potential Low education is connected to having more severe grief

Type of loss Potential Losing a child of any age to a violent sudden death

Pre-death dependency Primary High levels of pre-death marital dependency Attachment style Primary Avoidant/anxious/insecure attachment style Close kinship Primary Being a spouse or a parent of the deceased

traumatic nature) is a salient risk factor for PGD

3. Bereavement Risk Inventory and Screening Questionnaire (for the bereaved;

Monitor My Grief 4. PG-13 Grief severity

1. Background information Demographic data, such as age,

5. PCL Posttraumatic stress

8. ISLES-SF Meaning made of loss 9. PTGI Posttraumatic growth

6. CESD-R Depression 7. CD-RISC-10 Resilience

Scales #1–3 assess bereavement-related risk factors. Scales #4–9 have been empirically validated and are widely used in

distress

gender, ethnicity, religious affiliation

Proposed predictors of bereavement

Risk factors of Prolonged Grief

Basic information (including loss-related characteristics)

**Risk factors Primary or potential** 

Satisfaction with the death notification

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**risk factor**

bereavement research.

**Table 2.** Assessment instruments.

The research team evaluated both applications regarding the opportunities to yield trustworthy and quantifiable predictions in the earliest phase of bereavement. In comparison to My Grief Journal, which required a period of contemplation and was less precise in determining the positive and negative thinking style, GIFT exhibited better potential to offer users meaningful and objective feedback based on evaluating the factors that are relatively static and foreseeable even before the loss (**Figures 3** and **4**).

**Figure 3.** GIFT entry page.


**Figure 4.** GIFT slider scale.


**Figure 5.** Gift personalized report.

**Figure 6.** A slider for Likert scale answer.

In the end, GIFT was selected for further development and implementation to validate the proposed risk factors with a larger base of participants. To gauge the applicability of the app in the real life situation and optimize the user experiences of using it, five sessions of protocol analysis were conducted in the United States with the patients of one of the collaborative psychotherapists. The approval to conduct the study with the bereaved patients and to deploy the application through the Internet was sought in the respective Institutional Review Boards from both United States and the Netherlands, in which the former is where the study will be conducted and the latter is where the app was conceptualized and developed (**Figures 5**–**9**).

In the protocol analysis session, participants were prompted to "think out loud" on an individual basis as they completed the questionnaires by a certified thanatologist, who is also a graduating counseling student. After completion of the scales, participants were interviewed with questions regarding their general experiences of using GIFT, the wordings of the application as well as of the personalized feedback they received after completing the scales from the second section (Monitor My Grief). The protocol analysis sessions were all audio recorded and completely transcribed. Each session was approximately 1.5 hour long, generating approximately 7.5 hours of recording from the interview and the notes from the interviewer.

**Figure 7.** Slider response after an answer is indicated.

**Figure 8.** The responsive slider on a mobile device.

**Figure 6.** A slider for Likert scale answer.

**Figure 5.** Gift personalized report.

**Figure 4.** GIFT slider scale.

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Proceedings of the Conference on Design and Semantics of Form and Movement - Sense and Sensitivity, DeSForM

**Figure 9.** When user selects "N/A," it means that the statement could not apply to his/her situation.

### **5. Result**

The protocol analysis sessions for GIFT pilot testing were all audio recorded and completely transcribed. Each session was approximately 1.5 hour long, generating approximately 7.5 hours of recording from the interview and the notes from the interviewer. All of the participants were from the United States. There were total five participants, including one male and four female grievers. Their socio-demographic data are displayed in **Table 3**. Almost all of the participants bereaved about the loss of a family member. Of the total, 80% have received formal education for more than 13 years and had their religion. Participants who considered religion important practiced religious activity more frequently. Except PA3, who experienced death of a loved one around 6 months ago, the other participants generally experienced death of a loved one for more than 6 months to receive psychotherapeutic support. Two of our participants experienced unnatural death of a loved one such as suicide or fatal accident, and 60% of our participants were in contact with the deceased almost daily before the death happened.


Toward the Development of a Monitoring and Feedback System for Predicting Poor Adjustment… http://dx.doi.org/10.5772/intechopen.71109 37


**Table 3.** The socio-demographic data of the protocol analysis participants.

### **6. Discussion**

**5. Result**

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The protocol analysis sessions for GIFT pilot testing were all audio recorded and completely transcribed. Each session was approximately 1.5 hour long, generating approximately 7.5 hours of recording from the interview and the notes from the interviewer. All of the participants were from the United States. There were total five participants, including one male and four female grievers. Their socio-demographic data are displayed in **Table 3**. Almost all of the participants bereaved about the loss of a family member. Of the total, 80% have received formal education for more than 13 years and had their religion. Participants who considered religion important practiced religious activity more frequently. Except PA3, who experienced death of a loved one around 6 months ago, the other participants generally experienced death of a loved one for more than 6 months to receive psychotherapeutic support. Two of our participants experienced unnatural death of a loved one such as suicide or fatal accident, and 60% of our participants were in contact with the deceased almost daily before the death happened.

Proceedings of the Conference on Design and Semantics of Form and Movement - Sense and Sensitivity, DeSForM

**Figure 9.** When user selects "N/A," it means that the statement could not apply to his/her situation.

**Participant PA1 PA2 PA3 PA4 PA5** Gender of the participant Female Female Female Male Female Gender of the deceased Male Male Male Male Female

Age of the participant 70 39 32 61 31 Age of the deceased 70 26 40 87 95

> living together in a committed relationship

fiancé

Single Married or

living together in a committed relationship

Son Granddaughter

Single

Relation to the deceased Spouse Sister Partner/

Marital status Widowed Married or

The preliminary test of GIFT yielded fruitful data for future optimization. Since the three questionnaires from the background information were still under development, and the details of wordings and content refinement would not be of interest to the readers of this article, this discussion concentrated on the general experiences of using the app and participants' feedback on the applicability of this app in their bereavement process.

#### **6.1. Participants' experiences of searching for support on the Internet**

All of the participants were under bereavement intervention by professional therapist and trusted that they need professional counseling. We were particularly interested in participants' support seeking on the Internet, since this app was developed as an Internet-based app. Three out of five participants reported having searched for information related to bereavement or grief support on the Internet. One participant did not answer, and one indicated that she had never thought of searching for support on the Internet. The information on the Internet helped them to gauge their grief level or target the therapies that were available/ appropriate for them. One participant specifically stated that reading other people's stories

about surviving traumatic loss was helpful. Another participant indicated that grief is too personal and looking for support on the Internet did not feel safe.

In general, Internet sites, blogs, and forums were resources that participants could turn to when they needed immediate answer to their questions or information related to grief counseling or coping strategies. However, it was still obvious that participants were mostly prone to find a therapists or "somebody" who knows grief to support them, implying that bereavement-related services or information on the Internet, disregarding the quality of it, could face the difficulty to gain trust from the users. It could also be because most of our participants knew that they needed psychotherapeutic support at the first hand and only used the Internet to help them gain access to the services.

### **6.2. Participants' general experiences of using GIFT**

Most of the participants were satisfied with GIFT and found the feedback relevant, authentic, and reflective to their real situation and trustworthy. Some positive feedback pieces were as follows:


Some negative feedback pieces and suggestions were also reported:


#### **6.3. The evaluation of the performance of the app**

about surviving traumatic loss was helpful. Another participant indicated that grief is too

Proceedings of the Conference on Design and Semantics of Form and Movement - Sense and Sensitivity, DeSForM

In general, Internet sites, blogs, and forums were resources that participants could turn to when they needed immediate answer to their questions or information related to grief counseling or coping strategies. However, it was still obvious that participants were mostly prone to find a therapists or "somebody" who knows grief to support them, implying that bereavement-related services or information on the Internet, disregarding the quality of it, could face the difficulty to gain trust from the users. It could also be because most of our participants knew that they needed psychotherapeutic support at the first hand and only used the Internet

Most of the participants were satisfied with GIFT and found the feedback relevant, authentic, and reflective to their real situation and trustworthy. Some positive feedback pieces were as

• GIFT was a tool for thinking and widens awareness of the bereavement-related aspects.

• GIFT was a tool that enhance self-referring from grievers who obviously need grief

• Personalizing the questionnaires with the name of the deceased was really immersive, love

• The questionnaire results were similar to what the participant thought about herself, but it

• The feedback only presented shallow and "canned" responses to the questionnaires result. • It should connect to useful resources in the end of the feedback (e.g., books, grief counselors). • The fifth participant encountered enormous technical difficulties because of older version

• Participants should be "guided" through the process instead of choosing what questionnaires they should do next. The navigation had to be more clear and straightforward.

• The application should allow participants to share the results with others (e.g., sending the

• The session took too long to complete, and the data should be saved step by step.

personal and looking for support on the Internet did not feel safe.

to help them gain access to the services.

follows:

2017

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it.

counseling

was more validating.

of hardware.

report to their family or friends).

**6.2. Participants' general experiences of using GIFT**

• The process of using GIFT was therapeutic.

• The feedback was trustworthy and reassuring.

Some negative feedback pieces and suggestions were also reported:

Based on the participants' feedback, there were several points to take into consideration for next stage app refinement.

The problem of various usage platform: GIFT was a Web application, and we tested it with different devices such as computer, tablet, and mobile phone. One participant was using an iPhone 5S, and the questions and answers were completely overlapped. The problem could be caused by the older version of browser that did not support libraries such as jQuery. Designers usually need to take into consideration of how much the application was backward compatible and make a clear suggestion to the users.

The difference between mobile navigation and large screen navigation: on the larger screen, the questionnaire were separated into two groups and placed horizontally within each group. This design generated confusion for the participants who used tablet or laptop. One the mobile devices, the blocks were naturally sorted from top to bottom and participants who used mobile devices did not have problems related to navigation.

The app should add a function to share the report with other people.

Format of date: In the U.S., it would make more sense if the date was formatted as "month/ day/year." In this question, we provided a date picker powered by jQuery. However, it should be noted that the date format had to accustom to the familiar format of the participants.

There should be a save button where participants can review the in-progress questionnaires. This feature was added later on.

The environment of using this app should be suggested in the welcoming message. One participant mentioned that she would not be able to complete the questionnaires at home with her kids, suggesting that participant would appreciate a certain period of engagement in the app.

The app will welcome the users with a note of how long they could expect to complete the app in one session. In the introduction of each questionnaire, we should also indicate a time range of how long users usually take to complete the questionnaire.

Keywords such as "in the past month" in some questionnaires should be enlarged/bold and highlighted with visible colors. Some of the questionnaires such as PTSD or CESD-R were designed specifically to inquire the participants' experiences in the past months or past weeks. These keywords should be stressed since without emphasizing these conditions, the whole questionnaire could not precisely measure the participants' experiences.

The sliders in the questionnaires were nice, but there should be instructions of how to operate the sliders and the default option needed to be considered with caution. Some of the questionnaires were designed with Likert scale responses. Since the items in a Likert scale usually had a linear relationship between each other, it was a conscious choice of the research team to use a horizontal slider that allowed users to slide between each "pip" on the bar. However, researchers need to be very cautious in choosing where to place the default option or not to place it. In the study, the default option was placed in the 3rd Likert scale item. For instance from "Strongly disagree" to "Strongly agree," the default option was placed in the middle "Neither agree nor disagree." However, when the participants had the same answer with the default value, they simply skipped this question and realized that they needed to click or slide on the slider when trying to submit the questionnaire. It is important to provide certain instruction at the beginning that informs users how to interact with the slider

It should be explicit that the question has been answered, and the participants should be able to review their answers.

### **7. Conclusion**

Disregarding the obvious need to enhance the navigation and user experiences of the application, from the preliminary test, we could conclude that GIFT exhibits a good potential to be implemented in the early phase of bereavement and could empower the bereaved to be more attentive and autonomous to their grief response. Alone with the design of the application, a study was also planned to test GIFT with a larger base of participants and collect data that could be informative to validate the risk factors of PGD empirically. Modern technologies are more and more interwoven into our everyday life experiences. Grief was, and maybe still is, a highly private experience, but contemporary researchers have notified a growing phenomenon of bereaved individuals seeking social support and sharing their grief experiences or emotions on the Internet. Furthermore, the Internet likely also serves as a medium of communicating and connecting with the deceased. Examples are frequent addressing the deceased in a post on social media or talking to the deceased in a public forum. The effect of these phenomena remains unknown in both an intra- and interpersonal level but is by far worth heeding. More studies are being planned and will be presented elsewhere. We hope more results from the future studies can contribute to informing the field and professional practitioners how to better support the bereaved and facilitate positive health outcomes following the coping process of the bereavement.

### **Acknowledgements**

This work is funded by the Taiwanese Ministry of Education Funds for Studying Abroad. The authors want to thank Taiwanese government for sponsoring the study and Ph.D. project.

The authors also wish to address deepest gratitude to Laura Nelson for her professional execution in the protocol analysis sessions and to all the participants that contribute precious opinions regarding the contents and user experiences of the app.

### **Author details**

The sliders in the questionnaires were nice, but there should be instructions of how to operate the sliders and the default option needed to be considered with caution. Some of the questionnaires were designed with Likert scale responses. Since the items in a Likert scale usually had a linear relationship between each other, it was a conscious choice of the research team to use a horizontal slider that allowed users to slide between each "pip" on the bar. However, researchers need to be very cautious in choosing where to place the default option or not to place it. In the study, the default option was placed in the 3rd Likert scale item. For instance from "Strongly disagree" to "Strongly agree," the default option was placed in the middle "Neither agree nor disagree." However, when the participants had the same answer with the default value, they simply skipped this question and realized that they needed to click or slide on the slider when trying to submit the questionnaire. It is important to provide certain

Proceedings of the Conference on Design and Semantics of Form and Movement - Sense and Sensitivity, DeSForM

It should be explicit that the question has been answered, and the participants should be able

Disregarding the obvious need to enhance the navigation and user experiences of the application, from the preliminary test, we could conclude that GIFT exhibits a good potential to be implemented in the early phase of bereavement and could empower the bereaved to be more attentive and autonomous to their grief response. Alone with the design of the application, a study was also planned to test GIFT with a larger base of participants and collect data that could be informative to validate the risk factors of PGD empirically. Modern technologies are more and more interwoven into our everyday life experiences. Grief was, and maybe still is, a highly private experience, but contemporary researchers have notified a growing phenomenon of bereaved individuals seeking social support and sharing their grief experiences or emotions on the Internet. Furthermore, the Internet likely also serves as a medium of communicating and connecting with the deceased. Examples are frequent addressing the deceased in a post on social media or talking to the deceased in a public forum. The effect of these phenomena remains unknown in both an intra- and interpersonal level but is by far worth heeding. More studies are being planned and will be presented elsewhere. We hope more results from the future studies can contribute to informing the field and professional practitioners how to better support the bereaved and facilitate positive health outcomes fol-

This work is funded by the Taiwanese Ministry of Education Funds for Studying Abroad. The authors want to thank Taiwanese government for sponsoring the study and Ph.D. project.

The authors also wish to address deepest gratitude to Laura Nelson for her professional execution in the protocol analysis sessions and to all the participants that contribute precious

instruction at the beginning that informs users how to interact with the slider

to review their answers.

lowing the coping process of the bereavement.

opinions regarding the contents and user experiences of the app.

**Acknowledgements**

**7. Conclusion**

2017

40

Wan Jou She1 \*, Laurie Burke2 , Robert A. Neimyer2 , Kailey Roberts3 , Wendy Lichtenthal4 , Jun Hu1 and Matthias Rauterberg<sup>1</sup>


### **References**

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	- [13] van der Houwen K, Schut H, van den Bout J, Stroebe M, Stroebe W. The efficacy of a brief internet-based self-help intervention for the bereaved. Behaviour Research and Therapy. 2010;**48**(5):359-367
	- [14] Krysinska K, Andriessen K. On-line support and resources for people bereaved through suicide: What is available? Suicide and Life-Threatening Behavior. 2010;**40**(6):640-650
	- [15] Krysinska K, Andriessen K. Suicide bereavement online: Sharing memories, seeking support, and exchanging hope. Suicide Prevention and New Technologies: Springer. 2013:150-165
	- [16] Lundorff M, Holmgren H, Zachariae R, Farver-Vestergaard I, O'Connor M. Prevalence of prolonged grief disorder in adult bereavement: A systematic review and meta-analysis. Journal of Affective Disorders. 2017
	- [17] Bauer JJ, Bonanno GA. Doing and being well (for the most part): Adaptive patterns of narrative self-evaluation during bereavement. Journal of Personality. 2001;**69**(3):451-482
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	- [19] Maercker A, Bonanno GA, Znoj H, Horowitz MJ. Prediction of complicated grief by positive and negative themes in narratives. Journal of Clinical Psychology. 1998;**54**(8): 1117-1136
	- [20] Schnider KR, Elhai JD, Gray MJ. Coping style use predicts posttraumatic stress and complicated grief symptom severity among college students reporting a traumatic loss. Journal of Counseling Psychology. 2007;**54**(3):344
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	- [23] Field NP, Filanosky C. Continuing bonds, risk factors for complicated grief, and adjustment to bereavement. Death Studies. 2009;**34**(1):1-29
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[25] Lombardo L, Morelli E, Luciani M, Bellizzi F, Aceto P, Penco I, et al. Pre-loss demographic and psychological predictors of complicated grief among relatives of terminally ill cancer patients. Psychotherapy and Psychosomatics. 2012;**81**(4):256-258

[10] Beatty L, Lambert S. A systematic review of internet-based self-help therapeutic interventions to improve distress and disease-control among adults with chronic health con-

Proceedings of the Conference on Design and Semantics of Form and Movement - Sense and Sensitivity, DeSForM

[11] Landro L. Doctors prescribe new apps to manage medical conditions. Wall Street Journal.

[12] Vanderwerker LC, Prigerson HG. Social support and technological connectedness as protective factors in bereavement. Journal of Loss and Trauma. 2004;**9**(1):45-57

[13] van der Houwen K, Schut H, van den Bout J, Stroebe M, Stroebe W. The efficacy of a brief internet-based self-help intervention for the bereaved. Behaviour Research and Therapy.

[14] Krysinska K, Andriessen K. On-line support and resources for people bereaved through suicide: What is available? Suicide and Life-Threatening Behavior. 2010;**40**(6):640-650

[15] Krysinska K, Andriessen K. Suicide bereavement online: Sharing memories, seeking support, and exchanging hope. Suicide Prevention and New Technologies: Springer.

[16] Lundorff M, Holmgren H, Zachariae R, Farver-Vestergaard I, O'Connor M. Prevalence of prolonged grief disorder in adult bereavement: A systematic review and meta-analy-

[17] Bauer JJ, Bonanno GA. Doing and being well (for the most part): Adaptive patterns of narrative self-evaluation during bereavement. Journal of Personality. 2001;**69**(3):451-482

[18] Capps L, Bonanno GA. Narrating bereavement: Thematic and grammatical predictors of

[19] Maercker A, Bonanno GA, Znoj H, Horowitz MJ. Prediction of complicated grief by positive and negative themes in narratives. Journal of Clinical Psychology. 1998;**54**(8):

[20] Schnider KR, Elhai JD, Gray MJ. Coping style use predicts posttraumatic stress and complicated grief symptom severity among college students reporting a traumatic loss.

[21] Burke LA, Neimeyer RA. Prospective risk factors for complicated grief. Complicated

[22] Burke LA, Neimeyer RA, McDevitt-Murphy ME. African American homicide bereavement: Aspects of social support that predict complicated grief, PTSD, and depression.

[23] Field NP, Filanosky C. Continuing bonds, risk factors for complicated grief, and adjust-

[24] Lobb EA, Kristjanson LJ, Aoun SM, Monterosso L, Halkett GK, Davies A. Predictors of complicated grief: A systematic review of empirical studies. Death Studies. 2010;

grief: Scientific Foundations for Health Care Professionals. 2013:145

ditions. Clinical Psychology Review. 2013;**33**(4):609-622

2015

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42

2010;**48**(5):359-367

2013:150-165

1117-1136

**34**(8):673-698

sis. Journal of Affective Disorders. 2017

adjustment to loss. Discourse Processes. 2000;**30**(1):1-25

Journal of Counseling Psychology. 2007;**54**(3):344

OMEGA: Journal of Death and Dying. 2010;**61**(1):1-24

ment to bereavement. Death Studies. 2009;**34**(1):1-29


**Provisional chapter**

### **The Design Process and Usability Assessment of an Exergame System to Facilitate Strength for Task Training for Lower Limb Stroke Rehabilitation an Exergame System to Facilitate Strength for Task Training for Lower Limb Stroke Rehabilitation**

**The Design Process and Usability Assessment of** 

DOI: 10.5772/intechopen.71119

Edgar R. Rodríguez Ramírez, Will Duncan, Scott Brebner and Kah Chan Scott Brebner and Kah Chan Additional information is available at the end of the chapter

Edgar R. Rodríguez Ramírez, Will Duncan,

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/intechopen.71119

#### **Abstract**

Successful stroke rehabilitation relies on early, long-term, repetitive and intensive treatment, which is rarely adhered to by patients. Exergames can increase patients' engagement with their therapy. Marketed exergaming systems for lower limb rehabilitation are hard to find and, none yet, facilitate Strength for Task Training (STT), a novel physiotherapeutic method for stroke rehabilitation. STT involves performing brief but intensive strength training (priming) prior to task-specific training to promote neural plasticity and maximize the gains in locomotor ability. This research investigates how the design of an exergame system (game and game controller) for lower limb stroke rehabilitation can facilitate unsupervised STT and therefore allow stroke patients to care for their own health. The findings suggest that specific elements of STT can be incorporated in an exergame system. Barriers to use can be reduced through considering the diverse physiological and cognitive abilities of patients and aesthetic consideration can help create a meaningful system than promotes its use in the home. The semantics of form and movement play an essential role for stroke patients to be able to carry out their exercises.

**Keywords:** engagement, rehabilitation, stroke, exergame, game controller, serious games, strength for task training

### **1. Background**

With over 15 million cases worldwide every year [1], strokes are a leading cause of serious long-term disability [2, 3]. Up to 75% of people affected by stroke have lower limb mobility limitations [3, 4], including hemiplegia (muscle paralysis) or hemiparesis (muscle weakness)

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2017 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

down one side of the body [5]. The World Health Organization (WHO) has highlighted the need for home health care that calls for rehabilitative devices, self-monitoring tools and selfmanagement skills [6].

Success for stroke rehabilitation relies on early, intensive, long term repetitive treatment to regain motor control [5, 7] by learning to use existing redundant neural pathways [8]. However, although abundantly prescribed by clinicians, as little as 31% of patients perform these exercises correctly and consistently, often due to their monotonous nature [9].

Recent studies show that systems of rehabilitative devices with incorporated digital games for exercising (exergames) improve patient engagement with their home-based therapies. This has promoted beneficial patient outcomes for different long-term conditions, including upper limb stroke rehabilitation [5, 10, 11], and more effective recovery [12]. While there exist systems designed for upper-limb stroke rehabilitation [5, 13, 14] and for improving gait and balance [15–17], only one was found targeted specifically towards lower limb stroke rehabilitation [18].

#### **1.1. Strength for task training**

Strength for task training (STT) is a novel and promising approach to lower limb stroke rehabilitation [19]. STT combines priming the brain for learning through strength-based exercises, with task-specific movements promoting neural plasticity. Neural plasticity finds new pathways or rebuilds obsolete ones in the brain. These pathways establish the connection between the brain and subsequent muscle movement. Relearning these movements helps the patient attain better locomotion [19]. Priming involves the strengthening of the muscles using a weight or a resistance band while getting the patient to exert themselves as much as possible. This exertion creates corticomotor excitability. This primes the neural pathways in the brain so when followed promptly with task-specific training the brain is better equipped to promote neural plasticity [19].

While there are many systems of exergames for stroke rehabilitation, there currently exists an opportunity for the development of an exergame system that facilitates unsupervised STT for home-based lower limb rehabilitation. As an adjunct to clinical rehabilitation, this system could help promote therapy, optimizing recovery of lower limb function and reduce the load on the public health system.

### **2. Methodology**

This project reports on the design and usability testing of a system that involves an exergame and game controllers for facilitating home-based STT for stroke rehabilitation. We used a research-through-design approach based on design criteria through a user centered and iterative design (UCD) methodology to involve the clinicians and stroke patients in the designing of the system [5, 14, 20]. Shirzad et al. [14] proposed that UCD for rehabilitative exergames consists of three stages:


Initial design criteria were developed through literature and design reviews [21, 22], expert reviews, workshops and interviews with stroke clinicians [23]. The design reviews included hundreds of sketches, paper models and quick prototypes. The interviews and workshops involved a PhD and practitioner in physiotherapy, a PhD and neurophysiologist expert in stroke rehabilitation, a PhD and Associate Professor psychologist and a PhD and Senior Lecturer in a Graduate School of Nursing, Midwifery and Health. Initially, we interviewed clinicians through semi-structured interviews and asked them how they facilitate STT. We developed hundreds of sketches and showed them to clinicians in a design workshop that lasted 3 hours to discuss the different ways in which STT could be deployed. The most promising concepts were prototyped and showed to clinicians in an expert review workshop that lasted 3 hours.

The design criteria are listed in **Table 1**. The list of criteria was used to design and build prototypes, test them with participants and clinicians, iterate several times and then to assess the final designs. The list of criteria was also useful to explicitly communicate the design knowledge produced through this research-through-design process. There is much embedded tacit design knowledge within the designed products in this type of research-through-design processes that it is necessary to make it explicit to clarify the findings of the research.

#### **Function**

down one side of the body [5]. The World Health Organization (WHO) has highlighted the need for home health care that calls for rehabilitative devices, self-monitoring tools and self-

Proceedings of the Conference on Design and Semantics of Form and Movement - Sense and Sensitivity, DeSForM

Success for stroke rehabilitation relies on early, intensive, long term repetitive treatment to regain motor control [5, 7] by learning to use existing redundant neural pathways [8]. However, although abundantly prescribed by clinicians, as little as 31% of patients perform

Recent studies show that systems of rehabilitative devices with incorporated digital games for exercising (exergames) improve patient engagement with their home-based therapies. This has promoted beneficial patient outcomes for different long-term conditions, including upper limb stroke rehabilitation [5, 10, 11], and more effective recovery [12]. While there exist systems designed for upper-limb stroke rehabilitation [5, 13, 14] and for improving gait and balance [15–17], only one was found targeted specifically towards lower limb stroke rehabili-

Strength for task training (STT) is a novel and promising approach to lower limb stroke rehabilitation [19]. STT combines priming the brain for learning through strength-based exercises, with task-specific movements promoting neural plasticity. Neural plasticity finds new pathways or rebuilds obsolete ones in the brain. These pathways establish the connection between the brain and subsequent muscle movement. Relearning these movements helps the patient attain better locomotion [19]. Priming involves the strengthening of the muscles using a weight or a resistance band while getting the patient to exert themselves as much as possible. This exertion creates corticomotor excitability. This primes the neural pathways in the brain so when followed promptly with task-specific training the brain is better equipped to

While there are many systems of exergames for stroke rehabilitation, there currently exists an opportunity for the development of an exergame system that facilitates unsupervised STT for home-based lower limb rehabilitation. As an adjunct to clinical rehabilitation, this system could help promote therapy, optimizing recovery of lower limb function and reduce the load

This project reports on the design and usability testing of a system that involves an exergame and game controllers for facilitating home-based STT for stroke rehabilitation. We used a research-through-design approach based on design criteria through a user centered and iterative design (UCD) methodology to involve the clinicians and stroke patients in the designing of the system [5, 14, 20]. Shirzad et al. [14] proposed that UCD for rehabilitative exergames

these exercises correctly and consistently, often due to their monotonous nature [9].

management skills [6].

2017

46

tation [18].

**1.1. Strength for task training**

promote neural plasticity [19].

on the public health system.

**2. Methodology**

consists of three stages:

The design should provide sufficient load for intensive hip abduction and extension during the priming component

The design should enable the user to perform part and whole tasks to maintain intensity during the task training component

#### **Ergonomics and usability**

The shoe should be able to be put on and taken off using one hand

The design should allow for load to be removed quickly and easily to facilitate priming

The design should allow for load to be added/removed handsfree

The shoe and weighted sole should be able to be put on and taken off without written instruction

The design should be easy to setup and use, reducing the number of steps required for interaction

The design should use materials that consider the movement of the stroke patient

The design should be comfortable

The design should be usable for patients at different stages of recovery

The design should allow for increasing complexity and challenge to facilitate the state of flow and increase engagement

The design should involve competition as an option to increase engagement

The design should include positive feedback along its many interactions and avoid negative feedback to increase engagement

The design should involve social interaction to increase engagement

#### **Aesthetics**

Areas of high contrast should help distinguish between the shoe's inner and outer Areas of high contrast should help distinguish Key points of interaction The designs aesthetic should reflect contemporary footwear appropriate for the audience The user should not feel embarrassed wearing and using the design The games should look like a game familiar to the audience

**Table 1.** List of design criteria that the design should fulfill based on literature review, review of existing systems, expert reviews, interviews with clinicians and stroke patients.

Initial concepts were produced and assessed using a decision matrix model [24]. This model involved using several potential designs assessed next to prioritized criteria. The criteria were developed and revisited based on literature research, interviews with clinicians and finally user testing. Concepts were evaluated accordingly until a final design concept was formed for subsequent prototyping. Prototypes were reviewed by clinicians then iterated. Subsequent prototypes were submitted to user testing with stroke patients.

#### **3. Iterative design process**

#### **3.1. Selection of technology**

Based on feedback from interviewed clinicians and from a review of the literature and existing devices, the following criteria were decided upon for the technology to be used (**Table 2**). From the clinician's perspective, the technology should allow STT movements to act as inputs for playing the exergame, including priming and task exercises. The literature includes similar exergaming systems that rely on stationary cameras (for instance Kinect), balance boards (Wii balance board), remote controls (Wii remote) or movement sensors. We compared those systems with the initial criteria for the selection of technology in **Table 2**.

#### **3.2. Defining the therapeutic intervention**

In discussion with neuro-physiotherapist experts in STT, two STT exercises were chosen based on their feasibility of being emulated in an unsupervised environment as inputs for the game: Hip abduction and hamstrings (**Table 3**).

#### **3.3. Design process**

#### *3.3.1. The physical game controller*

The prototypes tested of the physical controller were made up of two components: a pair of shoes and a weighted sole. The weighted sole can facilitate up to 2500 g of weight for use in intense strength priming.

The Design Process and Usability Assessment of an Exergame System to Facilitate Strength… http://dx.doi.org/10.5772/intechopen.71119 49


A: The design should allow STT movements to act as inputs for playing an exergame; B: The design should allow the user to perform priming and task exercise uninhibited by the game controller; C: The design should be reliably accurate; D: The design should be of a similar price to commercial gaming system; E: The design should be easy to setup and use, reducing the number of steps required for interaction; F: The design should be able to be played anywhere in the home; G: The design should have easy to use controls.

**Table 2.** Criteria for selection of technology.

After many iterations, the final concept builds on the idea of a slipper with a modular sole system. A sleeve around the ankle was added for resistance band attachment and the upper folds across the foot for ease of access. Shoe lasts, which are used to create the pattern for a shoe's upper, were digitally modeled and then 3D printed and iterated. This process allowed the experimentation with different last shapes that represent the dynamic foot types of stroke patients due to spasticity.

Load is applied differently to the foot according to the STT exercise. The priming component for hip abduction requires load to be applied to the foot using a resistance band. The priming component for hamstrings requires weight to be attached to the foot using a Westminster pulley. Modular soles of different weights were proposed to facilitate similar load to what is applied using the Westminster pulley.

#### *3.3.2. The game*

Initial concepts were produced and assessed using a decision matrix model [24]. This model involved using several potential designs assessed next to prioritized criteria. The criteria were developed and revisited based on literature research, interviews with clinicians and finally user testing. Concepts were evaluated accordingly until a final design concept was formed for subsequent prototyping. Prototypes were reviewed by clinicians then iterated. Subsequent

**Table 1.** List of design criteria that the design should fulfill based on literature review, review of existing systems, expert

Proceedings of the Conference on Design and Semantics of Form and Movement - Sense and Sensitivity, DeSForM

Based on feedback from interviewed clinicians and from a review of the literature and existing devices, the following criteria were decided upon for the technology to be used (**Table 2**). From the clinician's perspective, the technology should allow STT movements to act as inputs for playing the exergame, including priming and task exercises. The literature includes similar exergaming systems that rely on stationary cameras (for instance Kinect), balance boards (Wii balance board), remote controls (Wii remote) or movement sensors. We compared those

In discussion with neuro-physiotherapist experts in STT, two STT exercises were chosen based on their feasibility of being emulated in an unsupervised environment as inputs for the

The prototypes tested of the physical controller were made up of two components: a pair of shoes and a weighted sole. The weighted sole can facilitate up to 2500 g of weight for use in

prototypes were submitted to user testing with stroke patients.

Areas of high contrast should help distinguish between the shoe's inner and outer

The designs aesthetic should reflect contemporary footwear appropriate for the audience

Areas of high contrast should help distinguish Key points of interaction

The user should not feel embarrassed wearing and using the design

The games should look like a game familiar to the audience

reviews, interviews with clinicians and stroke patients.

systems with the initial criteria for the selection of technology in **Table 2**.

**3. Iterative design process**

**3.2. Defining the therapeutic intervention**

game: Hip abduction and hamstrings (**Table 3**).

**3.1. Selection of technology**

**Aesthetics**

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**3.3. Design process**

*3.3.1. The physical game controller*

intense strength priming.

Based on feedback from clinicians, the final game is a set of dominoes, with the intention that our target audiences would be familiar with the game's mechanics. Initially, the player performs


**Table 3.** Definition of exercises selected to design the games: hip abduction and hamstrings.

strength-based priming exercises while wearing the weighted sole. This movement in turn shuffles a bag of dominoes in the game. Players progress through the game by performing sets of task exercises to push their dominoes into the desired position on the board. For instance, performing sideways walking task exercises moves the chosen piece of dominoes sideways to the desired location on the board. Mapping these rehabilitative processes to their in-game equivalents intends to help maintain immersion.

### **4. User testing**

#### **4.1. Users**

Testing of the exergame system involved the smart shoe, weighted sole and gaming media. We completed three sessions of tests of the system at stroke clubs at 2-week interval with the findings influencing iterations to the design between each session. Inclusion criteria: aged >18; had experienced a disabling stroke; has or has experienced hemiplegia or hemiparesis following their stroke and can walk without standby assistance. Exclusion criteria: significant cognitive deficit; unable to follow a one step verbal command; unable to give informed consent; medically unsuitable in the opinion of the screening physiotherapist, G.P. or medical specialist; experiences excessive joint pain and suffering other conditions that could impact results (e.g. substance abuse, significant mental illness such as major depression).

Recruited participants (N: 3) included: one with left hemiplegia with little to no use of his left arm due to contractures and no fine motor control over his left leg; one can walk unassisted but has minor weakness on the right side of her body and one has right hemiparesis with minor issues with her balance.

#### **4.2. Testing protocol**

With consent from participants, testing took place in their homes. User testing took 25–30 min and involved usability testing followed by a short semi-structured interview and filling of a Geneva Emotion Wheel [25]. User testing involved the user putting on the smart shoe and playing one round of the Dominoes game 12–12 on the iPad. The game then prompted them to put on, use and remove the weighted sole for the priming component, followed by repetitions of STT's task component. Hip abduction and sideways walking were observed. The think aloud protocol was used to assist our observation to fill usability heuristics. Usability heuristics were created based on the relevant criteria that informed the ergonomic and usability requirements of the design.

#### **4.3. User testing sessions**

Three user testing sessions took place and design iterations addressed issues found in each testing sessions. **Table 4** and **Figures 1**–**4** show some of the main findings from the user testing sessions and how the redesign addressed them.


strength-based priming exercises while wearing the weighted sole. This movement in turn shuffles a bag of dominoes in the game. Players progress through the game by performing sets of task exercises to push their dominoes into the desired position on the board. For instance, performing sideways walking task exercises moves the chosen piece of dominoes sideways to the desired location on the board. Mapping these rehabilitative processes to their in-game equiva-

Proceedings of the Conference on Design and Semantics of Form and Movement - Sense and Sensitivity, DeSForM

Testing of the exergame system involved the smart shoe, weighted sole and gaming media. We completed three sessions of tests of the system at stroke clubs at 2-week interval with the findings influencing iterations to the design between each session. Inclusion criteria: aged >18; had experienced a disabling stroke; has or has experienced hemiplegia or hemiparesis following their stroke and can walk without standby assistance. Exclusion criteria: significant cognitive deficit; unable to follow a one step verbal command; unable to give informed consent; medically unsuitable in the opinion of the screening physiotherapist, G.P. or medical specialist; experiences excessive joint pain and suffering other conditions that could impact results (e.g. substance abuse, significant mental illness such as major depression).

Recruited participants (N: 3) included: one with left hemiplegia with little to no use of his left arm due to contractures and no fine motor control over his left leg; one can walk unassisted but has minor weakness on the right side of her body and one has right hemiparesis with

With consent from participants, testing took place in their homes. User testing took 25–30 min and involved usability testing followed by a short semi-structured interview and filling of a Geneva Emotion Wheel [25]. User testing involved the user putting on the smart shoe and playing one round of the Dominoes game 12–12 on the iPad. The game then prompted them to put on, use and remove the weighted sole for the priming component, followed by repetitions of STT's task component. Hip abduction and sideways walking were observed. The think aloud protocol was used to assist our observation to fill usability heuristics. Usability heuristics were created based on the relevant criteria that informed the ergonomic and usabil-

Three user testing sessions took place and design iterations addressed issues found in each testing sessions. **Table 4** and **Figures 1**–**4** show some of the main findings from the user test-

lents intends to help maintain immersion.

**4. User testing**

minor issues with her balance.

ity requirements of the design.

ing sessions and how the redesign addressed them.

**4.3. User testing sessions**

**4.2. Testing protocol**

**4.1. Users**

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#### **How the re-design addressed the feedback**

#### **Feedback from user testing session 3**

The following issues were resolved: participants found the revised order of strapping a lot more intuitive and easy to use. All participants reported the shoes were a lot more comfortable and secure than the previous design. All participants could quickly remove the weighted sole after priming.

Issues observed: one participant had trouble with getting the vamp over the top of his affected foot. One participant required assistance in engaging the weighted sole.

No participant reported feelings of embarrassment towards wearing the shoes. Two participants commented that they would be proud to wear the shoes in their homes. One of them expanded on this saying he enjoyed that he was wearing something that "useful (to his rehabilitation) and fashionable".

Two participants related their feelings of enjoyment and relief towards the hardware as it symbolized their steps towards making progress towards regaining their independence.

**Table 4.** Feedback from the user testing sessions and how the design iterations addressed them.

**Figure 1.** Helping a participant put on the shoes in the first user testing session.

**Figure 2.** The design of the shoe is intended to be used with one hand, which participants could do well.

The Design Process and Usability Assessment of an Exergame System to Facilitate Strength… http://dx.doi.org/10.5772/intechopen.71119 53

**Figure 3.** A participant using the game on a tablet.

**How the re-design addressed the feedback**

**Feedback from user testing session 3**

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remove the weighted sole after priming.

(to his rehabilitation) and fashionable".

progress towards regaining their independence.

in engaging the weighted sole.

The following issues were resolved: participants found the revised order of strapping a lot more intuitive and easy to use. All participants reported the shoes were a lot more comfortable and secure than the previous design. All participants could quickly

No participant reported feelings of embarrassment towards wearing the shoes. Two participants commented that they would be proud to wear the shoes in their homes. One of them expanded on this saying he enjoyed that he was wearing something that "useful

Two participants related their feelings of enjoyment and relief towards the hardware as it symbolized their steps towards making

**Table 4.** Feedback from the user testing sessions and how the design iterations addressed them.

Proceedings of the Conference on Design and Semantics of Form and Movement - Sense and Sensitivity, DeSForM

**Figure 1.** Helping a participant put on the shoes in the first user testing session.

**Figure 2.** The design of the shoe is intended to be used with one hand, which participants could do well.

Issues observed: one participant had trouble with getting the vamp over the top of his affected foot. One participant required assistance

**Figure 4.** The physical game controller system: shoe, weighted sole, recharging dock, iMu sensors and cables.

### **5. Final design**

Final changes to the design addressed small aesthetic and usability concerns brought up in the final user test. The vamp was given slightly more stretch to help with the upper stretching over the foot to reduce time taken to put the shoe on. Red stitching was used on the toe clips to highlight what foot the user should be using the weighted sole. A small magnet was added to both the back of the heel clip and the fabric loop to minimize risks of tripping. The form of the weighted sole was changed to minimize the look of complexity and bulkiness reported by participants. All mechanisms were internalized concealing any complexity. The form was also streamlined to take away any protruding componentry. The size of steel plates added to increase load was also changed. Small uniform profiles allow the weight to be changed at smaller increments and distributed evenly across the weighted sole. **Figures 5**–**8** show the final design of the shoe-game controller.

**Figure 5.** Putting on the weighted sole one-handed.

**Figure 6.** The iMu sensor clips into place on the back of the shoe.

**Figure 7.** The shoes clipped onto the weighted sole.

The Design Process and Usability Assessment of an Exergame System to Facilitate Strength… http://dx.doi.org/10.5772/intechopen.71119 55

**Figure 8.** Detail of the clipping mechanism for the weighted sole.

**Figure 5.** Putting on the weighted sole one-handed.

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Proceedings of the Conference on Design and Semantics of Form and Movement - Sense and Sensitivity, DeSForM

**Figure 6.** The iMu sensor clips into place on the back of the shoe.

**Figure 7.** The shoes clipped onto the weighted sole.

The final version of 12–12 has a reduced user interface and options menu to minimize the chance of overwhelming new players. Enough options were kept allowing for variation in the game's complexity with a failsafe to ensure the game remained playable regardless of what player changed. 12–12's tutorial feature was enabled by default, taking users through a predetermined game that allowed them to experience the different mechanics. The tutorial requires 15 priming exercises and 30 standard repetitions to complete. **Figures 9**–**13** show elements of the design of the game.

**Figure 9.** Progression of tasks to motivate users engage in their exercises. Left: "If I can do forty leg raises now…"; centre: "…I could be walking by the end of the month"; right: "…I can see my friends at the café down the road whenever I want".

**Figure 10.** Home menu of the game.

**Figure 11.** Initially, and to shuffle the box of dominoes, the user performs strength-based hip abduction exercises, which primes their brain for learning.

The Design Process and Usability Assessment of an Exergame System to Facilitate Strength… http://dx.doi.org/10.5772/intechopen.71119 57

**Figure 12.** Tabletop of the game.

**Figure 10.** Home menu of the game.

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primes their brain for learning.

**Figure 11.** Initially, and to shuffle the box of dominoes, the user performs strength-based hip abduction exercises, which

Proceedings of the Conference on Design and Semantics of Form and Movement - Sense and Sensitivity, DeSForM

**Figure 13.** To move the piece of dominoes, the user needs to perform their task exercises. In this case, sideways walking makes the piece of domino roll to the player's chosen location.

### **6. Discussion**

The findings from user testing of the system suggest that the hardware can facilitate aspects of STT in an unsupervised environment. Currently, STT is only conducted in a clinical environment. Facilitating STT through the medium of an exergame could provide an engaging way to motivate the user to perform this lower limb therapy intensively and consistently in their home. This not only can reduce the load on the public health system but also can help maximize patients' locomotive gains and retain their mobility and subsequently their independence.

The design requirements of the system proved to be complex due to the diversity in our target audience. The functional criteria of the hardware were primarily defined by the requirements of STT. Ergonomic and usability requirements aimed to minimize barriers to using the exergame in an unsupervised environment. Addressing the diverse cognitive and physiological abilities of stroke survivors was paramount to overcoming these obstacles. The aesthetics of the system were designed to address the stigma of medical intervention products within the hardware and make the exergame's interface as cohesive as possible for an audience unfamiliar with digital technology.

#### **6.1. Evaluation through design criteria**

The final designs were evaluated according to the design criteria developed throughout the process (**Table 5**).

#### *6.1.1. Functional requirements*

Priming and task training components of STT can be used as a means of interaction with gaming media. A gaming controller in the form of a smart shoe could be used to track movement of the lower limb noninvasively.

Initial user tests indicate that intensive hip abduction priming can be facilitated by securely and comfortably fixing load in the form of external weight to the smart shoe. Load must also be specific to the user's capabilities through adapting the weight of the sole. Avoiding resistance bands during unsupervised rehabilitation also circumvents fall risks and their observed erroneous use outside of a clinical context. By mitigating the use of resistance bands unsupervised this ensures the priming component is intensive yet safe and manageable, keeping the user motivated to continue using the exergaming system. Clinician review of the weighted sole also indicated that beyond STT, any unsupervised rehabilitative strength training could benefit from the design's ability to mitigate the use of resistance bands.

Maintaining intensity during the task training component requires increasing the complexity of the task. Complexity is increased across nine components, part and whole task being one element where the patient must complete more dynamic movements as they progress. Testing indicates that creating footwear that provides a comfortable and stable base of support can allow the user to perform movements of increased complexity this progression demands.


**6. Discussion**

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independence.

iar with digital technology.

*6.1.1. Functional requirements*

of the lower limb noninvasively.

process (**Table 5**).

**6.1. Evaluation through design criteria**

The findings from user testing of the system suggest that the hardware can facilitate aspects of STT in an unsupervised environment. Currently, STT is only conducted in a clinical environment. Facilitating STT through the medium of an exergame could provide an engaging way to motivate the user to perform this lower limb therapy intensively and consistently in their home. This not only can reduce the load on the public health system but also can help maximize patients' locomotive gains and retain their mobility and subsequently their

Proceedings of the Conference on Design and Semantics of Form and Movement - Sense and Sensitivity, DeSForM

The design requirements of the system proved to be complex due to the diversity in our target audience. The functional criteria of the hardware were primarily defined by the requirements of STT. Ergonomic and usability requirements aimed to minimize barriers to using the exergame in an unsupervised environment. Addressing the diverse cognitive and physiological abilities of stroke survivors was paramount to overcoming these obstacles. The aesthetics of the system were designed to address the stigma of medical intervention products within the hardware and make the exergame's interface as cohesive as possible for an audience unfamil-

The final designs were evaluated according to the design criteria developed throughout the

Priming and task training components of STT can be used as a means of interaction with gaming media. A gaming controller in the form of a smart shoe could be used to track movement

Initial user tests indicate that intensive hip abduction priming can be facilitated by securely and comfortably fixing load in the form of external weight to the smart shoe. Load must also be specific to the user's capabilities through adapting the weight of the sole. Avoiding resistance bands during unsupervised rehabilitation also circumvents fall risks and their observed erroneous use outside of a clinical context. By mitigating the use of resistance bands unsupervised this ensures the priming component is intensive yet safe and manageable, keeping the user motivated to continue using the exergaming system. Clinician review of the weighted sole also indicated that beyond STT, any unsupervised rehabilitative strength training could

Maintaining intensity during the task training component requires increasing the complexity of the task. Complexity is increased across nine components, part and whole task being one element where the patient must complete more dynamic movements as they progress. Testing indicates that creating footwear that provides a comfortable and stable base of support can allow the user to perform movements of increased complexity this progression demands.

benefit from the design's ability to mitigate the use of resistance bands.


**Table 5.** Assessment of final designs according to the design criteria.

The flexibility of game options allowed for 12-12 to be playable by a range of people with different physical capabilities. User tests made it apparent that there was a cognitive threshold to the game that meant survivors of stroke who had suffered severe cognitive deficits would not be able to play. A version of the game with reduced functionality, therefore reduced expectations of the player, would be necessary for making 12-12 accessible to this subgroup of our target demographic.

#### *6.1.2. Contextual requirements*

*Ergonomics and usability.* The dynamic range of abilities that survivors of stroke possess must be addressed to ensure that the patient can use lower limb exergame hardware independently and intuitively. To consider the physiological effects of hemiparesis, one-handed interaction was necessary to complete all tasks. Observation of tests indicated that, apart from Ned needing assistance to put on the weighted sole, participants could put on and take off the shoe and weighted sole independently. It is critical that hardware promotes its use across all ability levels.

Reducing time between strength and task training components was crucial to facilitate priming. User observation illustrated that the design of the weighted sole enabled the user to remove load and promptly begin task training. This suggests that the hardware can maximize corticomotor excitability during strength training to subsequently enhance neural plasticity during the task component. Effective priming maximizes the patient's gains in locomotive ability helping them regain independence.

An unanticipated but important outcome was the feeling of pride participants felt after figuring out how to complete certain interactions with the exergame system. We speculate that reducing cognitive/physical challenges rather than removing them completely could create a more beneficial experience for the user. In addition to this, it is apparent that more consistent feedback from the system to the user will help maintain their confidence in its use. Our user testers enjoyed the 'you can do it' mentality of the game and wished to see more feedback throughout their experience that let them know if they were progressing or not.

*Aesthetics.* Feedback suggests that aesthetic consideration of exergame hardware can remove any medical semantics and address the stigma towards using medical devices. By designing a game controller that was considered a "fashionable" piece of footwear, the user avoided the feeling of embarrassment while wearing and using the smart shoes. Counter to the praise of the footwear's aesthetic, the weighted sole receives critique on its perceived complexity.

Beyond "fashionable" semantics, the aesthetic seemed to resonate on a deep emotional level with participants. The design elicited emotions that relate to positive progress that the patient was making in their recovery. Moreover, participants seemed to find that wearing shoes does not just make rehabilitation novel and motivating but also can act as a tool to help them regain their independence. Furthermore, just knowing that there was something designed specifically for them made the user feel valued as a person. Based on these results we speculate that the aesthetics of an exergame controller could transcend the stigma towards medical devices and help create a meaningful object that represents the survivor of stroke's journey back to independence.

Lastly, the aesthetic of the game yielded no complaints from participants. They reported it to be vibrant and the text was easy to read. This aligned with the works of [26], Gerling et al. [27], Ijsselsteijn et al. [28], Kopacz [29] and Martin et al. [30], which informed most of the design decisions regarding the game's interface.

### **7. Conclusion**

The flexibility of game options allowed for 12-12 to be playable by a range of people with different physical capabilities. User tests made it apparent that there was a cognitive threshold to the game that meant survivors of stroke who had suffered severe cognitive deficits would not be able to play. A version of the game with reduced functionality, therefore reduced expectations of the player, would be necessary for making 12-12 accessible to this subgroup of our

**Initial design criteria Assessment based on design criteria Explicit design knowledge applicable to** 

Proceedings of the Conference on Design and Semantics of Form and Movement - Sense and Sensitivity, DeSForM

All participants were keen to participate in competition through the game.

All participants reported feeling encouraged by the feedback in the

All participants were keen to play with other participants through the game.

There was no report on this from participants. When prompted, they agreed that it was easy to distinguish.

of interaction.

Participants were able to find key points

All participants expressed that the shoes and designs had high aesthetic appeal.

The participants initially expressed their desire to own the system and did not

All participants understood the game as a dominoes game immediately.

express embarrassment.

**Table 5.** Assessment of final designs according to the design criteria.

game.

**this system based on criteria**

games.

Competition based on known games (in this case dominoes) resulted in a natural understanding and willingness to engage in competition in rehabilitative

Feedback based on pop up messages as individual tasks are completed (for instance shuffling the dominoes pieces or moving individual pieces within the game) can be encourage for participants.

A social interaction based on an already known game (dominoes) was easy to adapt to an acceptable social interaction

High contrast can help distinguish between shoe's inner and outer when this is important for the interaction.

Areas of high contrast can help users distinguish key points of interaction.

The design of the aesthetics of shoes for rehabilitation is both discernable for users and important for their willingness to use them.

The aesthetic of rehabilitative system can influence the desire of users to own the system and avoid embarrassment.

Using a game familiar to the audience can help with its intuitive use.

in game for rehabilitation.

*Ergonomics and usability.* The dynamic range of abilities that survivors of stroke possess must be addressed to ensure that the patient can use lower limb exergame hardware independently and intuitively. To consider the physiological effects of hemiparesis, one-handed interaction

target demographic.

The design should involve competition as on option to increase engagement.

The design should include positive feedback along its many interactions and avoid negative feedback to increase

The design should involve social interaction to increase

Areas of high contrast should help distinguish between the shoe's inner and outer.

Areas of high contrast should help distinguish key points of

The design aesthetic should reflect contemporary footwear appropriate for the audience.

The user should not feel embarrassed wearing and using

The games should look like a game familiar to the audience.

engagement.

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engagement.

**Aesthetics**

interaction.

the design.

*6.1.2. Contextual requirements*

Stroke is a leading cause of disability in developing nations leading to impairments affecting patients' locomotion and limiting their independence. Research into exergames for rehabilitation is an emerging field; however, the benefits they present make further exploration

a necessity. STT is a novel intervention for lower limb stroke rehabilitation, which aims to promote gains in locomotion, however currently only practiced in a clinical environment. This research has contributed to the greater field of exergame rehabilitation tools by investigating how the design of an exergame controller could facilitate unsupervised STT for lower limb stroke rehabilitation.

The functional and contextual requirements of an exergame and its controller were explored through background research and interviews with stroke clinicians. These initial requirements informed the design and prototyping of exergame and its controlling hardware as part of an exergaming system for unsupervised STT.

Smart footwear that interacts with an adaptable strength training weighted sole to control an exergame was prototyped and tested. Functional requirements of the system promoted a way to strength training safely and comfortably by applying load to the lower limb. The weighted sole that provides load was removed to promptly begin task training to facilitate the merits of priming. The interactions with the system needed to be intuitive and facilitate a one-handed interaction. Aesthetic consideration of the hardware and exergame indicated that the system could disrupt the stigma of using medical devices in the home and become a meaningful HCI system in the user's life.

Reviews with clinicians and feedback from user testing with stroke patients helped to substantiate and build on the functional and contextual requirements and to better understand how exergaming systems can facilitate clinical interventions like STT. The growing population of stroke patients represent a diverse and complex demographic target group. The final design could benefit from further testing with a wider user base of patients over longer periods of time.

There is a growing amount of research examples in the field of exergaming media design; however, little research furthering the design of purpose built game controllers has been done. There is undiscovered potential through a designerly approach to exergaming HCI. More case studies into these processes could help foster an abundance of novel and innovative design discoveries and broaden the abilities of home-based rehabilitation systems.

We have presented a complete exergaming system with meaningful HCI that is user friendly and provides a safe way to participate in home based stroke rehabilitation. This research has proposed a way to enhance the lives of survivors of stroke and potentially the wider population of people living with muscular disabilities, such as multiple sclerosis and cerebral palsy. Further research into similar systems can benefit the ageing population and assist those seeking to reclaim their independence, and it should involve a full assessment on the effectiveness of the system to improve stroke rehabilitation and its ability to increase adherence to therapies.

### **Acknowledgements**

The Center of Research Excellence in Medical Technologies (CoRE MedTech), New Zealand, funded this project.

### **Author details**

a necessity. STT is a novel intervention for lower limb stroke rehabilitation, which aims to promote gains in locomotion, however currently only practiced in a clinical environment. This research has contributed to the greater field of exergame rehabilitation tools by investigating how the design of an exergame controller could facilitate unsupervised STT for lower

Proceedings of the Conference on Design and Semantics of Form and Movement - Sense and Sensitivity, DeSForM

The functional and contextual requirements of an exergame and its controller were explored through background research and interviews with stroke clinicians. These initial requirements informed the design and prototyping of exergame and its controlling hardware as part

Smart footwear that interacts with an adaptable strength training weighted sole to control an exergame was prototyped and tested. Functional requirements of the system promoted a way to strength training safely and comfortably by applying load to the lower limb. The weighted sole that provides load was removed to promptly begin task training to facilitate the merits of priming. The interactions with the system needed to be intuitive and facilitate a one-handed interaction. Aesthetic consideration of the hardware and exergame indicated that the system could disrupt the stigma of using medical devices in the home and become a meaningful HCI

Reviews with clinicians and feedback from user testing with stroke patients helped to substantiate and build on the functional and contextual requirements and to better understand how exergaming systems can facilitate clinical interventions like STT. The growing population of stroke patients represent a diverse and complex demographic target group. The final design could benefit from further testing with a wider user base of patients over longer peri-

There is a growing amount of research examples in the field of exergaming media design; however, little research furthering the design of purpose built game controllers has been done. There is undiscovered potential through a designerly approach to exergaming HCI. More case studies into these processes could help foster an abundance of novel and innovative

We have presented a complete exergaming system with meaningful HCI that is user friendly and provides a safe way to participate in home based stroke rehabilitation. This research has proposed a way to enhance the lives of survivors of stroke and potentially the wider population of people living with muscular disabilities, such as multiple sclerosis and cerebral palsy. Further research into similar systems can benefit the ageing population and assist those seeking to reclaim their independence, and it should involve a full assessment on the effectiveness of the system to improve stroke rehabilitation and its ability to increase adherence to

The Center of Research Excellence in Medical Technologies (CoRE MedTech), New Zealand,

design discoveries and broaden the abilities of home-based rehabilitation systems.

limb stroke rehabilitation.

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system in the user's life.

ods of time.

therapies.

**Acknowledgements**

funded this project.

of an exergaming system for unsupervised STT.

Edgar R. Rodríguez Ramírez\*, Will Duncan, Scott Brebner and Kah Chan

\*Address all correspondence to: edgar.rodriguez@vuw.ac.nz

Victoria University of Wellington, Wellington, New Zealand

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[15] Fritz SL, Peters DM, Merlo AM, Donley J. Active video-gaming effects on balance and mobility in individuals with chronic stroke: A randomized controlled trial. Topics in

[16] Gil-Gómez J-A, Lloréns R, Alcañiz M, Colomer C. Effectiveness of a Wii balance boardbased system (eBaViR) for balance rehabilitation: A pilot randomized clinical trial in patients with acquired brain injury. Journal of NeuroEngineering and Rehabilitation.

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[18] YouRehab – Interactive Rehabilitation Systems [Internet]. [cited 2017 Mar 7]. Available

[19] Signal NEJ. Strength for Task Training: A Novel Intervention to Improve Locomotor Ability Following Stroke [Internet] [Thesis]. Auckland University of Technology; 2014 [cited 2017 Mar 6]. Available from: http://aut.researchgateway.ac.nz/handle/10292/8011

[20] Billis AS, Konstantinidis EI, Ladas AI, Tsolaki MN, Pappas C, Bamidis PD. Evaluating affective usability experiences of an exergaming platform for seniors. In: 2011 10th

[21] Booth WC, Colomb GG, Williams JM, Bizup J, Fitzgerald WT. The Craft of Research. 4th ed. Chicago: The University of Chicago Press; 2016. p. 316 (Chicago guides to writing,

[22] Martin B, Hanington BM. Universal Methods of Design: 100 Ways to Research Complex Problems, Develop Innovative Ideas, and Design Effective Solutions. Digital ed. Beverly,

[23] Goodman E, Kuniavsky M, Moed A. Observing the User Experience: A practitioner's Guide to User Research [Internet]. Burlington, MA: Elsevier Science; 2012 [cited 2017 Mar 7]. Available from: http://public.eblib.com/choice/publicfullrecord.aspx?p=978450

International Workshop on Biomedical Engineering. 2011. p. 1-4

Therapy. 2015 Mar;**95**(3):415-425

Stroke Rehabilitation. 2013 Jun;**20**(3):218-225

Research International. 2015;**2015**:342529

from: http://yourehab.com/

editing, and publishing)

MA: Rockport Publishers; 2012 207 p

Italy 27-300715. 2015;

2017

64

2011;**8**(1):30


**Provisional chapter**
