**3.3 Vision problems and teaching**

Research that was originally conducted with visually impaired students and with people who suffered vision loss after brain injuries show that "vision" is a learned process thus can be improved through structured teaching. Such knowledge is valuable for all educators and should have consequences for our education systems.

*Natalie Barraga* [27] was the first vision teacher who carried out research in relation to structured visual education in order to teach children with a visual impairment to use their remaining vision better. She developed exercises focusing on visual discrimination and recognition using objects with different sensory qualities: size, figure, contrast, and color. In her lessons, she taught children to discriminate and reflect on forms and objects and connect the forms to their surrounding objects. Her findings revealed that structured vision education increased the childrens' functional vision and resulted in more visual effectiveness.

Later research confirmed that visual qualities like VA, the attention in VF, and different ocular motor functions including accommodation and convergence can develop through structured learning [28]. Gislén et al. [29] were impressed of the VA capacity that the pearl divers showed under water, but afterward they trained some Swedish children who rather quickly reached the same underwater VA level. Behavioral optometrists have focused on children with eye motor disorders and have shown how better eye movements trough structured procedures also improve the VA at near and distance [6, 30–33].

*Walter Poppelreuter* [34], a psychologist and medical doctor, developed vision rehabilitation strategies for soldiers suffering from vision problems after gunshot wounds to their heads during World War I. Soldiers with reduced VF, the area of vision outside the fixation, learned eye movement techniques as compensation strategies [10]. These experiences laid the foundation for rehabilitation of vision problems following neurological disorders like stroke or traumatic brain injuries [7, 35, 36]. Cyvin and Wilhelmsen [37] demonstrated how a girl with brain damage got better balance and motor functions parallel to improved binocular vision.

All visual sensory and ocular motor functions are connected in a visual circle where the eye motor capacities influence sensory and perceptual functions and vice versa [38]. Tiny eye motor disturbances may affect concentration, attention, endurance, social communication, reading and writing, and motoric activities and have a negative influence on the ability to manage assigned tasks [33, 39]. Even communication with others is to a large degree visually mediated. Not only is the written communication visual, but we also use nonverbal communication when facial expressions and body language interpret the message we want to send. Therefore, increased vision will even positively influence social behavior and motor activities which rely on visual inputs [10, 37].

The conclusion that many visual functions such as VA, VF, accommodation, convergence, and ocular motor control are important for receiving clear visual inputs in learning and communication can be drawn from the discussion above. Thus, this importance for learning needs visual screenings to be comprehensive and inclusive of all visual functions involved in learning. In addition, vision is a developing sense; for it to thrive, it needs a stimulating environment provided by teachers and other caretakers. However, evidence from the literature show that visual function problems can be improved through intervention. Yet, most school vision programs however do not screen for all those visual functions mentioned, although their impact on academics, particularly reading, is significant [40].

## **4. Impact of visual problems on the reading process**

When learning to read, the first important activity is to learn the sounds connected to the visual forms of each letter and how to combine sounds and form them into words. Visually, there is a need of being able to see the difference between a **t** and a **f** or depart an **o** from an **e**. This requires good VA for distance, so they can see the blackboard clearly and a good accommodation capacity and convergence for clear near inputs. For being able to read the letters in the correct order, the eyes need to focus together on the same spot. If not, it is difficult to decide if the word is **follow** or **flow**, **spot** or **ptos**. Letters will be turned around, or if the fixation is unsteady, they will even be seen jumping around. For children with ocular motor disturbances, the same word may appear differently during each time it is seen.

This phase is followed by a period where reading develops and turns into an automatic process where the child can read for learning [41] and understand the meaning of the texts. The child must develop a strategy where perceiving the text turns automatic, without great effort [42]. This level may be difficult to reach if vision is a challenge. Some can manage for a short time, but then the vision system is worn out and the text turns blurry or double.

Seeing the text clearly is of fundamental importance and requires a good VA. VA tests are presenting letters, numbers, or symbols with smaller and smaller sizes on each line down the chart. The most common tests are normally the distance VA tests carried out on 6 m or 20 ft, although some used for children are standardized for 3 m. If the line marked 6/6, 3/3 or 20/20 is seen from the actual test distance, the VA is normal. Full VA means that the symbols expected to be seen at 6 m, 3 m, or 20 ft are seen on this distance and noted as 6/6, 3/3 or 20/20 or as decimal number 1.0. If the 6/12 line is the last line seen, the vision is in decimals 0.5, which is the border line for the category of visual impairment in ICD-11 [9]. Then symbols that were expected and seen at 12 m (40 ft) are seen at 6 m (20 ft). For reading from the blackboard or seeing objects clearly from a longer distance, it is important to have good distance VA. Students with problems seeing objects far away are often nearsighted, having myopia [42].

It is important to remember that a normal distance VA is no guarantee for a clear VA at a reading distance. Therefore, it is also necessary to screen the near VA separately with a VA chart developed for 40 cm or 3 ft. It is a harder ocular motor activity to see clearly at near because the lenses need to adjust, or accommodate, and more and more the closer they must focus. Children with accommodation problems will perceive the text as foggy or blurry at near. Because the regulation of the lens is muscle work through the ciliary muscle in the eye, some children may lose the power to keep the accommodation over time. After some minutes, it will be demanding and tiring to continue reading [42]. A near VA test can show if the child has accommodation problems, a hypermetropia. The new ICD-11 [9] also categorizes a near VA as a visual impairment, if it is less than 0.5. This criterion is new compared to previous classifications. Together with testing the accommodation ability, the near VA test is an important predictor of visual discomfort for reading and other near activities [43].

The VA tests are done monocularly, with each eye alone, and binocularly, with both eyes together, to see if each eye has a good VA and if they function well together. When looking at something in the distance, the eyes normally stay in a parallel position and the eye lens has a relaxed shape. When looking at something closer, both eyes must not only accommodate, but also converge inward to fixate on the same spot. If the eyes are not fixated on the exact same spot during reading, double images will occur. Disturbed convergence is a binocular problem [6]. Students who struggle with double vision, will sometimes unconsciously supress the visual inputs from one

#### *Learning Is Visual: Why Teachers Need to Know about Vision DOI: http://dx.doi.org/10.5772/intechopen.93546*

eye and only depend on the information from the better eye. The supressed eye will turn into a so-called "lazy eye," with reduced VA [42].

The classic treatment of an amblyopic eye is to patch the good eye for hours each day, so the weak eye is used and stimulated [44]. The result may be two eyes with a good VA, but they will not always function well together—an ability that is essential for reading. Students may manage near-work in school if the letters are large and the reading time is limited. But they can have problems with reading, when the letters are smaller, the text gets longer, the line space is reduced, and the period of reading increases. The text may turn unclear and double and the eyes may even hurt. Some are then even rubbing their eyes or turning very sleepy.

The measured VA gives only information about the very central area of the vision where the gaze is fixated. The VF around the fixation point informs about the surroundings and what is happening there. This visual information tells the brain where to look next, what to be aware of through colors, forms, and movements. These signals are catching our interest and attention, and we move the gaze to new places for seeing the details clearly. Even in reading, VF is important. It contributes to the reading speed and reading flow. Only the awareness of the entire picture of the text can give information about what is coming and where the gaze must continue. With this information, the brain prepares where to place the next fixation. The gaze jump, or saccade, normally places the next fixation in the first part of the next word. Reading consists of continuous new saccades and fixations, and during this eye motor activity, the eyes must work well together to prevent double images [6, 42]. This shows how essential well-functioning binocular activities are for effective saccades and fixations during reading [45].

There are more accommodation challenges among school children than previously known [33]. In a group of nearly 400 schoolchildren, between 8 and 15 years, only 54% were found to have normal accommodation and convergence [46]. These are serious findings due to the connection between ocular motor disturbances and reading difficulties [41, 47]. Often, children with such problems receive refraction with plus lenses to relax the lens and to make text appear larger. However, this treatment may help children to overcome their accommodation problem but not necessarily their binocular disturbances [42]. So, prescribing glasses is not always enough or the best help for their visual reading challenges [48]. To train and strengthen the accommodation capacity on the other side has shown a good and long-lasting effect on reading [6, 10, 49]. Strengthening the ocular motor control and capacity will give better visual sensor qualities, especially the VA increases through better accommodation and steady fixation [10, 33].

The evidence theme that is emerging from this paragraph is that reading is a highly complex visual activity which relies upon intact visual functions. Some visual functions can be improved with eyeglasses, but not all. In terms of learning, it appears that many different visual functions have to be checked and also that there has to be some awareness of teachers that these functions are important. Otherwise, they may miss important signs of their students to indicate a visual problem. In addition, there is also the question what other types of intervention are identified by the literature if glasses are not the sole solution for visual problems that children may exhibit during learning [3, 22].

#### **5. Screening and intervention of vision problems in school**

The functional consequences of a vision problem are often misunderstood and may be interpreted as signs of dyslexia or attentional disturbances [6, 22, 50]. Because vision inputs are so fundamental for the learning and reading process,

vision should be checked regularly. There is even an increase in vision disturbances through the years in school [51]. Children themselves are seldom aware of their vision problems, so several states in the United States have rules for checking childrens' vision during the years in school [52].

Teachers can learn to screen VA for near and far [4, 14] and other visual functions in their classrooms and identify visible eye health problems, for example, changes of the eye appearance, eye movement problems such as eyes moving in different directions and squinting. However, often the vision screening is incomplete, not addressing those latter problems [40]. Metsing et al. [13] also point out that in vision screening programs around the world, there often is a priority to identify problems related to distance vision to detect amblyopia and related problems, such as strabismus, in preschool children. Accommodation and convergence are often not screened for even though those functions are very important for reading and writing in older children. An issue, however, is also about training of the screeners. Screeners need to be educated well to be able to screen properly for many visual functions and avoid high false-positive or high false-negative identification [13].

Early on, Rogers [3] was convinced that teachers would identify many pupils with vision problems if they were better observers. Signs like making mistakes with letters and figures, holding the text abnormally close or leaning forward when reading something far away, and complaining about headache or blurry vision are still signs that a teacher has to take seriously. They can observe and notice light sensitivities in their students and become alarmed if a student is copying from their neighbors instead directly from the blackboard. When students are easily bored of doing near work or read slowly, teachers could become aware that the student may have vision disturbances. Equipped with knowledge and skills, teachers can communicate their findings to parents and the eye health system and ensure that there is follow-through with recommendations.

Students with accommodation and convergence problems may need structured vision training of the eyes in order to improve their reading skills. Even though there is still controversy about the main cause of reading problems, whether they are phonetic or visual in nature, there is evidence that visual training does improve reading outcomes, especially in poor readers and even children with dyslexia [53–55]. This training is usually done by experts in the field of behavioral optometry. However, there may also be a lack of optometrists, ophthalmologists, and eye health-care workers in many countries, particularly in developing countries [56, 57], so children may not have access to such training. There is also evidence that teachers can be educated to systematically stimulate childrens' visual capacities in a structured way [42].

From the literature, it appears that particularly eye movement disorders, accommodation, and convergence problems are often not screened for in vision screening programs. This is true for many countries around the world. These problems also cannot be changed through glasses alone but may need more structured vision training to improve.

#### **6. Results and discussion of the literature review**

In the next paragraphs, results and discussion of the results are presented. Each major result of the literature review is discussed separately.

*Vision is a learnt and developing sense and can be stimulated by teachers and caregivers to improve best developmental outcome.*

#### *Learning Is Visual: Why Teachers Need to Know about Vision DOI: http://dx.doi.org/10.5772/intechopen.93546*

Possibly all teachers should have knowledge about the role of vision in learning as part of their education. Such information can be delivered through teacher training and continuing education programs for teachers. Just even greater awareness of the importance of vision may be important to provide better learning environments. Teachers sometimes can prevent visual problems if they offer a visually stimulating environment and pedagogy particularly in preschools. They can educate students, parents, and caretakers about the importance of eye health and intact visual functions. Especially in developing countries, parents may not know about the signs and symptoms of visual problems or eye diseases, such as conjunctivitis [58]. Teachers can also provide an environment that is conducive to learning, with good lighting conditions, for example, and materials that have universally good visual features in form and contrast, such as clearly legible materials. Improved teacher training in the area of vision may be an important prerequisite to higher academic achievement in children. This however requires governments to invest in Continuing Professional Development (CPD) courses and in teacher training at the preservice level in the area of vision.

*Academic learning such as reading can be negatively impacted by visual problems. Intact visual functions such as visual acuity, visual field, ocular motor control, accommodation, and convergence are necessary for learning.*

Even though there is debate about the role of vision in areas such as reading difficulties and dyslexia, evidence was provided in how impaired visual functions can have an impact on reading. Reading difficulties cannot be attributed solely on visual problems, however, when children do exhibit reading problems, a thorough screening and assessment should take place [59]. This requires teachers being aware of the effect of visual problems on learning. It also needs a functioning networking system where teachers can refer children to for screening and intervention.

*Teachers can learn to screen for visual functions. School screenings need to encompass all visual functions involved in learning, not just visual acuity testing for distance vision.*

In different parts of the world, teachers have been trained in VA screenings [4, 14], but screening for many different visual functions, evaluating the results, making decisions for further steps, and ensuring follow-through does not fully occur [40]. However, for teachers to be able to do this and become successful screeners, it seems obvious that they have to be trained well [60]. There are several questions that must be answered regarding the training and who should be trained. In many countries, teachers of the visually impaired/blind (TVI) teach children with visual impairments, that means children who have a VA loss or a VF loss after correction of refractive error. These teachers have a foundation of knowledge in vision. They, however, would have to undergo a role change in that they would not only be responsible for children with significant visual impairment due to VA and VF loss, but they would also have to get involved with children that may have problems in learning due to eye movement problems, accommodation, or convergence problems. It would need to be researched further whether ordinary classroom teachers or specialist teachers, such as teachers of the visually impaired, should be educated further to conduct a comprehensive vision screening for all children. The exact manner through which school-based screenings are organized is also dependent on the specific context and country. Historically vision screening was primarily done by eye health professionals, which is the medical sector. The medical and

educational system in a specific country would have to begin to work together in a more coordinated way, also to ensure valid screening results and follow up in children. The issue of false-positive or false-negative identification of children through screening by teachers when compared with screening results conducted by ophthalmologists is a concern. However, it appears that with training this can improve, and the benefits outweigh the risks [61].

*Teachers can learn to intervene when visual problems occur. They can network and collaborate with eye health-care providers. A child may need more structured vision training/intervention to improve vision for learning.*

The issue of intervention can be even more challenging. Children with significant visual impairment or blindness classified by ICD-11 (after correction for refractive error) usually receive services by a TVI and often are taught compensatory skills and receive alternative materials to print reading. Children who need correction for refractive error only receive eyeglasses.

As we pointed out before, some problems that affect reading can be ameliorated with spectacles, but not all. Eyeglasses which are important in treating refractive errors such as myopia and hyperopia are necessary in many cases. The World Health Organization estimates that globally over 1 billion people have visual impairment due to uncorrected refractive error [62]. However, eyeglasses do not solve all visual problems that impact learning, such as accommodation and convergence problems. Teachers need to come to realize that even though a child is wearing eyeglasses and has seen an eye doctor, they may still struggle visually and need a different plan of intervention. Even children who have had their eyes checked but did not receive glasses may still have vision challenges. Eyeglasses may also not be sustainable for many children, particularly those from families that lack the financial resources to see an ophthalmologist or optician on a regular basis. For example, in some African countries peer pressure, costs, and availability of optical services were identified as the main barriers to spectacle wear in children [63].

There is also controversy with regard to vision training or "vision therapy" as it is also often called. Usually, this training is conducted not by medical eye doctors or teachers but by optometrists. There is a continuous debate about the benefits of vision training besides the controversy about who should actually do it [64]. There is however a consensus that vision therapy does work for visual disorders such as convergence insufficiencies. This leads to reading problems and reading aversions [65]. Much of this chapter is focused on precisely those types of problems, namely, of both eyes working together, which can have adverse effects on learning.

Eye health professionals may not always realize the impact of vision problems relevant to learning. For teachers to begin to address childrens' vision problems in the school setting, this also would require a whole system wide approach and again collaboration between the medical and educational sectors.

Methodologically, this study was an integrated literature review. This also poses some limitations of the study, mainly the question whether all relevant information and studies on the topics were included. Further studies using different methodologies should continue to explore the relationship between vision and learning and particularly the relationship between the medical and educational systems when it comes to the area of vision screening and intervention. This study aimed at opening the discussion about a possible model of training teachers in the area of vision. Further studies and research must occur to identify benefits and problems/barriers of teachers conducting vision screenings and interventions in schools. However, the results of this review could help to inform the design of such a model of teachers' training, while taking also into account the country and regional specifications.
