**2. Method and procedure**

**1.4. Early recognition of pathological cognitive decline by visuoconstructive and** 

Assessment of cognitive impairments in the elderly is an important task of modern cognitive neuropsychology. Neuropsychological evaluation can respond to the expectations of valid and reliable differentiation of pathological from normal aging if it is accomplished by sufficiently sensitive, specific, and standardized psychometric tools [14]. The use of such tools is a requirement of the diagnostic algorithm for early discrimination of dementia from normal aging [9, 58]. The widely applied strategy to administer global clinical scales for screening and quantifying the level of individual cognitive deficit has low specificity, particularly in subjects with high or very low level of premorbid cognitive functioning and in the early stages of impairments in elderly [5, 14]. Short tests, assessing specific cognitive dysfunctions, are more

In order to detect age-related visual-spatial and constructive decline early enough, specific neuropsychological techniques are required. Such measures could be efficient and helpful if they take into account the age-related and pathological cognitive changes and assure accuracy of the assessment. Many different neuropsychological instruments are used to test the spatial functions [45]. The visuoconstructive ability is traditionally assessed by drawing of two- or three-dimensional figures [51, 52, 54] and block-building tasks [55] of varying complexity. Drawing neuropsychological tasks can detect the deficits in reproducing shapes, following their relationships in space, but it is difficult to standardize them [51], and in most cases, subject drawings are assessed "intuitively" and very rarely through an objective assessment

Drawing as a cognitive ability is not well studied in late-life adults. It is a complex multicomponent ability that engages perception, representation, memory, attention, spatial thinking, planning, and motor functions. Better knowledge of the structure of drawing process in old adults as well as of its age-related impairments can contribute to a more successful study of

Our study tests the hypothesis that short and easy-to-use visuoconstructive and visuospatial tests can be used to distinguish normal from pathological cognitive aging in its very early stages if appropriate, accurate, and valid criteria are applied. We use drawing of cube and drawing of house, together with other traditionally used and well-proven neuropsychological instruments—Benton Visual Retention Test (BVRT) and Block design—assessing visual

The aims of this chapter are to explore the visuoconstructive and visuospatial abilities in nor-

**1.** The discriminative capacities of a set of visuoconstructive and visuospatial neuropsychological tasks in the differentiation of pathological (CIND) from normal cognitive aging

mal and in pathological aging (CIND) above 60 years of age and to analyze:

visual constructive and visual-spatial functions and their disturbances in old age.

memory, perception, constructional, and spatial abilities.

**spatial tasks**

172 Gerontology

system [52].

**1.5. Aims of the chapter**

over 60 years of age.

accurate than the global cognitive scales [14, 59].

#### **2.1. Subjects and recruitment**

The participants in this study were individuals over 60 years of age with normal daily functioning and without self-reported history of psychiatric and neurological disorders, residents of Plovdiv region*,* living independently in the community. The sample was divided in two groups: healthy subjects (MMSE ≥28), without cognitive complaints, and individuals with CIND (MMSE between 24 and 27 and subjective cognitive complains). The decision to accept the diagnostic category CIND was substantiated by the design of the study, which did not include the possibility of conducting detailed clinical, laboratory, and neuroimaging studies. After testing, all the participants from CIND group were advised to seek consultation from a general practitioner or neurologist to accurately identify the cause of the condition and the need for treatment. A total of 216 subjects were recruited for this study with the help of clubs for the elderly; 28 of them dropped out due to age below 60 years, impairments in every day functioning, visual disturbances that hindered neuropsychological testing, data from the interview about mild mental retardation, and test data for severe cognitive deficits. Only participants defining themselves as right handers were included in the study. Basic demographic characteristics of the study groups are shown in **Table 1**.


Note: 1, primary and secondary school; 2, high school; and 3, college/university.

**Table 1.** Subject basic demographics.

#### **2.2. Instruments**

Assessment of correspondence to the inclusion criteria (administered to all subjects):

**1.** Mini-Mental State Examination (MMSE) [60], Bulgarian translation [61]—a short global scale for cognitive functioning, with subtests for spatial and temporal orientation, concentration, memory, aphasia, agnosia, and apraxia [8, 62]. The scale is the most widely used screening tool for cognitive impairments in late life in Bulgaria.

reproduction received one point— and (2) specific types of errors (quality assessment). Types of errors for which points were awarded were as follows: (a) omissions, (b) distortions, (c)

Differentiating Normal Cognitive Aging from Cognitive Impairment No Dementia: A Focus…

http://dx.doi.org/10.5772/intechopen.73385

175

Subjects received two white sheets of paper (15 × 21 cm) for the free drawings of cube and house and black pencil with rubber. The drawings were assessed following a modification of the scoring system of Moore and Wyke [52] developed by the author: One point was given for each line drawn from the front, top, and side walls of the cube (maximum nine points). Orientation of the cube was not evaluated. For the additional qualitative criteria of Moore and Wake, quantitative assessment (maximum of four points) was used. One point was given for three-dimensional representation, for the presence of additional elements (interior walls), for the cohesion of the figure, and for lack of spatial distortion (parallelism of the sides and

Written informed consent was obtained from all participants. The study design and procedure were approved by the ethics committee of Medical University in Plovdiv, Bulgaria.

In order to achieve the study objectives, it was necessary to analyze the differences in test performance between (1) "normal" subjects and subjects with CIND and (2) participants up to and above 70 years of age. Descriptive statistic (frequencies, percents, means, standard deviations) was used to describe the sample as well as for the analysis of results regarding general scoring criteria and error types in study groups; comparison of test performance in different subgroups was made by t-test and Mann-Whitney test; RSPM performance was additionally described using Z-scores and chi-square test. The relationships between study variables were studied with Pearson and Spearman correlations and multiple regression analysis. We performed a principal component analysis to explore the structure of visuoconstructive and

Significant differences in BVRT total scores—mean total number of correct reproductions and mean total number of errors—were found when the normal subjects, and the subjects with CIND were compared (p < .001) (**Table 2**). (We use the term "normal" and "healthy" subjects to distinguish between normal and pathological aging, taking into account the conditionality of its use.) There were significantly more omissions and distortions (BVRT) in CIND group than in the normal group (p < .001). These differences can also be seen in the BVRT frequency distribution data—50% of the healthy participants had between three and six correct reproductions and made between seven and 12 errors; 50% of participants with CIND reproduced correctly between two and four cards and made between 10 and 14 errors. As for the different types of

perseverations, (d) rotations, (e) misplacements, and (e) size errors.

accuracy of the corners).

visuospatial abilities, involved in the study tests.

**3. Results and interpretation**

**3.1. Performance in the diagnostic groups**

**2.4. Data analysis**


Neuropsychological assessment:


#### **2.3. Procedures**

The demographic and neuropsychiatric interviewing and the testing were conducted by a licensed clinical psychologist with experience in psychiatric disorder assessment (the chapter author). All the tests were administered individually on 2 separate days. To those who agreed to participate in the full 2-day testing (N = 62), all the study instruments were applied. The other participants (126) were tested with BVRT and RSPM. Subjects were assessed at the elderly club premises in prearranged days and hours.

BVRT cards were reproduced after a 10-s exposition (immediate recall trial) with the standard instruction and assessment: The subject was given 10 white sheets for the reproduction of the 10 test cards and pencil with rubber. Assessment took into account: (1) number of correct reproductions—each card reproduction is judged correct or wrong, and every correct card reproduction received one point— and (2) specific types of errors (quality assessment). Types of errors for which points were awarded were as follows: (a) omissions, (b) distortions, (c) perseverations, (d) rotations, (e) misplacements, and (e) size errors.

Subjects received two white sheets of paper (15 × 21 cm) for the free drawings of cube and house and black pencil with rubber. The drawings were assessed following a modification of the scoring system of Moore and Wyke [52] developed by the author: One point was given for each line drawn from the front, top, and side walls of the cube (maximum nine points). Orientation of the cube was not evaluated. For the additional qualitative criteria of Moore and Wake, quantitative assessment (maximum of four points) was used. One point was given for three-dimensional representation, for the presence of additional elements (interior walls), for the cohesion of the figure, and for lack of spatial distortion (parallelism of the sides and accuracy of the corners).

Written informed consent was obtained from all participants. The study design and procedure were approved by the ethics committee of Medical University in Plovdiv, Bulgaria.

## **2.4. Data analysis**

**2.2. Instruments**

174 Gerontology

Assessment of correspondence to the inclusion criteria (administered to all subjects):

screening tool for cognitive impairments in late life in Bulgaria.

ropsychiatric history and cognitive complains.

studies in Bulgaria on late-life RSPM performance.

**3.** Free drawing of a house and of a cube.

duced patterns (accuracy of performance).

elderly club premises in prearranged days and hours.

**2.3. Procedures**

Neuropsychological assessment:

**1.** Mini-Mental State Examination (MMSE) [60], Bulgarian translation [61]—a short global scale for cognitive functioning, with subtests for spatial and temporal orientation, concentration, memory, aphasia, agnosia, and apraxia [8, 62]. The scale is the most widely used

**2.** Semi-structured interview, collecting basic demographic information, and data on neu-

**1.** Benton Visual Retention Test (BVRT), form C, administration "A"—a well-known test of short-term visual memory, visual perception, and constructive ability. The "C" form is

**2.** Raven's Standard Progressive Matrices (RSPM)—a language and culture-free measure of fluid intelligence. The task comprises five sets of 12 black and white matrices, presenting pattern matching tasks with increasing difficulty, used as a test of general intelligence and nonverbal reasoning [65, 66]. The raw score is used in the analyses because of the lack of

**4.** Block design—a subtest from Hamburg-Wechsler Intelligence Test, Bulgarian adaptation [67]; the task requires construction of observed patterns—two, four, nine, and 16 elemental figures—from the same multicolored cubes, with standard instruction. The time for task completion is not assessed. The score used in this study is the number of correctly repro-

The demographic and neuropsychiatric interviewing and the testing were conducted by a licensed clinical psychologist with experience in psychiatric disorder assessment (the chapter author). All the tests were administered individually on 2 separate days. To those who agreed to participate in the full 2-day testing (N = 62), all the study instruments were applied. The other participants (126) were tested with BVRT and RSPM. Subjects were assessed at the

BVRT cards were reproduced after a 10-s exposition (immediate recall trial) with the standard instruction and assessment: The subject was given 10 white sheets for the reproduction of the 10 test cards and pencil with rubber. Assessment took into account: (1) number of correct reproductions—each card reproduction is judged correct or wrong, and every correct card

considered the easiest BVRT task that makes it appropriate for old adults [64].

**3.** The Social and Occupational Functioning Assessment Scale—SOFAS (DSM-IV) [3, 63].

In order to achieve the study objectives, it was necessary to analyze the differences in test performance between (1) "normal" subjects and subjects with CIND and (2) participants up to and above 70 years of age. Descriptive statistic (frequencies, percents, means, standard deviations) was used to describe the sample as well as for the analysis of results regarding general scoring criteria and error types in study groups; comparison of test performance in different subgroups was made by t-test and Mann-Whitney test; RSPM performance was additionally described using Z-scores and chi-square test. The relationships between study variables were studied with Pearson and Spearman correlations and multiple regression analysis. We performed a principal component analysis to explore the structure of visuoconstructive and visuospatial abilities, involved in the study tests.
