Article ID: WMC

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1 Article ID: WMC Immediate Memory Functioning and Intelligence Quotients of Years Age Group Using Ne Data Derived From the Benton Visual Retention Test: Applicability to Alzheimers Disease Patients Corresponding Author: Dr. Simon B Thompson, Associate Professor, Psychology Research Centre, Bournemouth University, BH12 5BB - United Kingdom Submitting Author: Dr. Simon B Thompson, Associate Professor, Psychology Research Centre, Bournemouth University, BH12 5BB - United Kingdom Article ID: WMC Article Type: Original Articles Submitted on:01-mar-2011, 03:50:51 PM GMT Article URL: Subject Categories:GERIATRIC MEDICINE Published on: 02-Mar-2011, 07:08:49 PM GMT Keyords:Alzheimers Disease,Benton Visual Retention Test; Correlation, Dementia, Immediate Memory; Intelligence Quotients, Memory, Normative Values, Wechsler, Younger Age Group Ho to cite the article:thompson S B, Gander J. Immediate Memory Functioning and Intelligence Quotients of Years Age Group Using Ne Data Derived From the Benton Visual Retention Test: Applicability to Alzheimers Disease Patients. WebmedCentral GERIATRIC MEDICINE 2011;2(3):WMC Source(s) of Funding: Source of funding: None. Competing Interests: Competing interests: None. WebmedCentral > Original Articles Page 1 of 27

2 Donloaded from on 24-Dec-2011, 10:01:46 AM Immediate Memory Functioning and Intelligence Quotients of Years Age Group Using Ne Data Derived From the Benton Visual Retention Test: Applicability to Alzheimers Disease Patients Author(s): Thompson S B, Gander J Abstract The aim of this study as to create a normative data set of performance scores for the Benton Visual Retention Test (BVRT) for individuals aged beteen 18 and 30 years. Previously, no normative data existed for BVRT performance for this particular age group.the data collected examined the correlation beteen cognitive functioning as tested by the Weschler Adult Intelligence Scale III (WAIS III) and BVRT.The Hospital Anxiety and Depression Scale (HADS) as used as a screening process to gain a cognitive profile of the sample population.fifty participants carried out the BVRT, WAIS III and HADS.The data collected ere analysed using the Pearson s Correlation Co-efficient and results indicated a strong relationship beteen BVRT performance across all three administrations and full IQ. In addition, strong relationships ere identified beteen Total Correct responses and Total Errors score ith Verbal IQ and Performance IQ. Hoever, no significant correlations ere found beteen Anxiety and Depression levels and BVRT performance, this may have been due to 90% of the sample being ithin a normal, healthy range.these findings suggest IQ levels are a strong indicator for BVRT performance. Furthermore, the development of a ne set of normative data for the year old age group, ill allo the use of the BVRT as a clinical instrument to assess brain damaged and diseased individuals more accurately, particularly those diagnosed ith Alzheimer s disease. Introduction Individuals may suffer from impaired cognition as a result of brain injury or brain disease. This could result in the skills and abilities the individual had prior to injury or disease onset, being significantly damaged or completely lost. Brain injury or disease can affect any part of the brain and the impairment can be displayed in any cognitive skills such as attention, communication, visual perception, and memory. Over 1.4 million people per year, sustain brain injury and one of the most common age groups at risk are year olds. Brain disease affects a considerably larger percentage of the population e.g. Alzheimer s alone exceeding 3 million each year (Fay, 2010) and Parkinson affects 12,000 people each year in the UK alone (Parkinson s disease Society, 2010). Most research investigating brain damage and disease has attempted to measure the extent of impairment on the individual s cognitive abilities. The Benton Visual Retention Test (BVRT) developed by Arthur L. Benton (Benton Sivan, 1992) is a idely used instrument, assessing individual s visual perception, visual memory and visuo-constructive abilities, for this reason it is highly valued in clinical settings (Thompson, Ennis, Coffin & Farman, 2007; Thompson, 2011). Lezak (1983) and many other neuropsychologists through time often use figure draings to assess people's deficits because of their sensitivity in detecting many types of cognitive impairments and diseases. This is the main strength of the BVRT. The BVRT has been used to assess brain disorders such as Attention-deficit hyperactivity disorder (ADHD), Alzheimer s disease, stroke patients, Bipolar disorder, Schizophrenia and many others. Marsh and Hirsch (2006) looked at the effectiveness of different neuropsychological tests and shoed the BVRT to be significantly more effective in detecting defective visual retention. They further recommend that it is highly valuable for evaluating brain damaged or diseased patients. Tasks hich are visual memory and visuo-spatial in nature have often been included in many intelligence scales (Binet & Simon, 1908). Hoever, these subtests ere not an adequate measure of any specific visual-memory or visuo-spatial abilities and so Arthur L. Benton designed his first edition of the BVRT (Benton, 1946). Since then revisions and improvements have been made and the BVRT is currently in its Fifth Edition (Benton Sivan, 1992). There are many ays of detecting brain damage and disease e.g. Tomography (fmri, PET, CAT) is a technique using gamma rays, ultrasound or x-rays to WebmedCentral > Original Articles Page 2 of 27

3 Donloaded from on 24-Dec-2011, 10:01:46 AM obtain detailed images of areas inside the body. Whilst these tests are effective in detecting physical damage, they cannot measure the amount of memory loss or capacity to sustain attention. Neuropsychological instruments have proven far more useful in determining an individual s cognitive function. Neuropsychological tests, such as the BVRT, are used to analyse and interpret the individual s responses to cognitive based tasks and compare performance to normative data. The results of these tests allo the psychologist to make inferences about hat the individual is able to do ithin his or her environment, by assessing their performance on the specific tasks relative to ho a cohort of healthy people ithin the same age range performed on the same set of tasks. By identifying brain-behaviour relationships, treatments can be tailored to focus on the individual s particular strengths to compensate for their limitations in cognitive functioning. In clinical settings the BVRT is often used as an instrument to determine cognitive function in the older population that are more susceptible to brain diseases such as Alzheimer s and Parkinson s disease. Whereas, in educational fields the main focus of the test has been to asses learning difficulties and attention disorders such as ADHD in young children up to early/mid teens. Currently there is a lack of research assessing cognitive function in late teens and young adults, or the data needs updating (eg Benton, Eslinger & Damasio, 1981). The existing normative data are based on children aged up to 15 and adults over the age of 30. The importance of the BVRT remains highly valued and it is important to have normative data to demonstrate the performance of individuals ithin this age group, thus providing a base line comparison for patients that may suffer from brain injury or disease that affects their cognitive function (Thompson, 2002). Existing normative data are based upon correlations ith IQ levels as this has been identified as a key factor in BVRT performance (Arenberg, 1978; Le Carret, inville, Lechevallier, Lafont, Letenneur & Fabrigoule. 2003; Emdad & Sondgaard, 2006). Cognitive decline in older populations Significant correlations beteen performance and chronological age have been identified, and in early detection of brain disease such as Alzheimer s concerning the older population. Arenberg (1978) studied males that had received a high level of education ith a good economic status, and found a gradual decline in BVRT performance from years of age, and an increased rate of number of errors hen completing the tasks from and years of age. Hoever as noted previously, research has indicated significant correlations beteen intelligence and BVRT performance, and so these findings may only be representative of individuals ith advanced levels of education. The research of Seo and colleagues (2007), offered further support to these findings. They looked at the BVRT performance of an educationally diverse elderly population on the BVRT and found that both age and education play a role in non-verbal memory and reconstructive abilities. Both older age and loer educational levels related to poorer performance on the BVRT. Poitrenaud and Clement (1965) carried out a similar study on a culturally diverse population; the findings support those of Seo and colleagues (2007). The BVRT Manual (fifth edition) provides normative data hich demonstrates a significant relationship beteen chronological age and BVRT performance; a progressive increase from 8 to 15 years of age (Benton Sivan, 1992). Performance begins to progressively decline through the fifties; a drop of about 1 point in mean number of correct score, then a further 2 points in the sixties. Benton concluded that performance on the BVRT declines significantly after the age of 60 years and inter-individual variability correspondingly increases. Various neuropsychologists have researched into hat changes occur ithin the brain that results in cognitive decline. It has been found that it may be as a result of a loss of synapses ithin circuits of the hippocampus and also a decrease in metabolic activity in the entorhinal cortex hich is the major input and output of the hippocampus. Leon (2001) found that in normal individuals, the level of metabolic activity in the entorhinal cortex can predict the amount of cognitive decline over the next 3 years. Alzheimer s disease and other brain diseases commonly affecting the older populations have been studied in some depth to understand the contribution of the disease to further impairment of the individual s cognitive abilities. Alzheimer s in particular, is characterised by progressive brain deterioration and impaired memory and other mental abilities. An article by Amieva and colleagues (2005) reported a 9 year cognitive decline prior to the onset of dementia, ith significantly lo performances on the BVRT even in the early years, hich progressively declined further ith time. It is hoever, important to note in longitudinal studies, such as this, other factors that may be responsible for the change need to be taken into account. Thompson, MacDonald and Coates (2001) carried out a study in hich they found, using a battery of neuropsychological tests including the BVRT, significant improvement on performance in both visuo-spatial and visual memory tests after 16 eeks WebmedCentral > Original Articles Page 3 of 27

4 Donloaded from on 24-Dec-2011, 10:01:46 AM of Aricept treatment used to improve the symptoms of Alzheimer s. Netherton and colleagues (1989) used the BVRT to study patients ith Parkinson s Disease, these patients shoed an increase in figural reproduction errors beteen test periods spaced six months apart, the control group hoever shoed no increase in errors over this time and feer errors in general. Poitrenaud and Barrere (1973) looked at 46 middle aged individuals ho had been either referred for neuropsychological testing or ho had reported having experienced mental difficulties. The study involved a battery of five tests, one of hich as the BVRT. Of the 46 patients, 31 performed normally and 15 performed defectively. Five years later the sample as assessed again. Subsequent testing shoed that of the 46, 30 ere diagnosed as mentally intact and 16 diagnosed ith dementia. Of the 16 patients diagnosed ith dementia, 14 ere from the original 15 that performed badly. The Rey Auditory-Verbal Learning Test, another of the other five battery tests, and the BVRT accounted for 93% of the correct prediction rate and individually shoing 85% predictive accuracy. Brain damage and disease in younger populations Disorders of a visuo-spatial nature are particularly prevalent after damage to the posterior parietal lobe, such as unilateral neglect. Balint s syndrome and constructional apraxia patients often have similar lesions ithin this region. Vilkki (1989) studied brain damaged patients ith lesions to the anterior and posterior areas of the brain. He shoed subjects ith anterior lesions made significantly more perseveration errors (figure in previous design replicated in reconstruction of folloing design) than subjects ith posterior lesions, ith both left and right hemispheres of the brain. Petris (1981) compared performance on the BVRT of brain damaged patients to control patients. Patients ith brain disease produced a higher average percentage of omission errors (28%) - single figure of a design being completely omitted or no recognisable attempt as made to reconstruct the figure - than the control group (14%), and higher frequency of size errors (2.7% vs. 0.3%) (Reconstruction rongly sized), yet made less perseveration errors than the control group (33% vs. 42%). Benton Sivan (1992) concluded that omission errors and size errors are particularly prominent in patients ith cerebral disease. Damage located toard the front of the brain tends to result in the most severe problems associated ith attention and concentration, hich could explain the omission and size errors found. The BVRT has been used in adults and younger individuals that have suffered from strokes and post-traumatic stress. By using the BVRT they have found a cognitive decline due to the impact of trauma on hippocampal functioning, hich affects memory. Emdad and Sondegaard (2006) studied Post Traumatic Stress Disorder (PTSD) patients by assessing intelligence levels using the ven Standard Progression Matrices (RSPM) (see Thompson, 2000; 2001; 2006; 2010), and visual memories using the BVRT. In comparison to the control group, the PSTD patients demonstrated a strong negative correlation beteen the BVRT and RSPM. PSTD patients shoed poor short term, non-verbal memory, and these deficits ere related to individual s intelligence. Hoever the same results ere not found in the control group, here comparable differences in RSPM score shoed no significant relationship to performance on the BVRT. In the younger population, the use of the BVRT in assessing learning difficulties in children and young adults has been extremely important in the improvement of their abilities and assessing their progress. Dige and Maarh (2008) studied patients ith different levels of ADHD. Using the BVRT, they ere able to sho ADHD patients performed considerably poorer in such tests, and the more severe the case of ADHD the higher the amount of errors. Park (2008) looked at Schizophrenic patients and the nature of visual recall and recognition through the use of the BVRT, she found that patient s performance as idely variable in visual memory and there as no significant difference beteen recall and recognition. From looking at research into the affects of these brain diseases and the use of the BVRT as a clinical instrument, it is clear to understand its value in this field. The BVRT appears to tap into a unique combination of skills that are characterised by both short-term memory and psychomotor abilities. The BVRT not only records here errors are made in responses, but also the different types of errors being made, this allos for assessment of qualitative as ell as quantitative patterns to facilitate more comprehensive interpretation. For example Robinson-Whelen (1992) reported a significant difference beteen controls and patients ith mild to moderate levels of dementia, specifically in the number of omission errors that ere made. Baum, Edards, Yonan and Storandt (1996) also found specific associations beteen test errors and Alzheimer s patients. Affects of mood disorders on cognition Anxiety and Depression are knon disorders that can impact performance on many cognitive based tasks (Eysenck, 1997, p.8). Such that if individuals are WebmedCentral > Original Articles Page 4 of 27

5 Donloaded from on 24-Dec-2011, 10:01:46 AM feeling anxious or depressed this may significantly affect their performance. Anxiety suggests that individuals may be tense, restless and have trouble concentrating on the current task at hand. Similar symptoms may be found in individuals that are depressed; fatigue, difficulty concentrating and lack of motivation ill affect performance and so ho they perform on a given task ill not be an accurate measure of ho they ould usually perform had they been in a calm, relaxed, healthy state. Especially in medical practice, it is very important to ensure that possible mood disorders such as depression and anxiety are not influencing a patient s performance. Weems and colleagues (2007) found certain cognitive errors demonstrated specific associations ith anxiety symptoms. Findings from Ellis and colleagues (2008) further support this, and shoed mild anxiety as associated ith better cognition, here more severe anxiety as associated ith orse cognition. Several studies have indicated that sufferers of severe depression may experience impairment in motivation, attention, and concentration. This is related to poor BVRT performance, hoever not as significantly as such illnesses as Dementia (Crookes & McDonald, 1972; Birch & Davidson, 2007). Research into the effects of less severe levels of Depression is yet to be completed and therefore the current findings are inconclusive. Intelligence and cognitive abilities In a vast amount of research on cognitive abilities a major factor has been intelligence. As educational levels increase so does performance on tests such as the BVRT, and so higher IQ scores suggest better cognitive skills. In the early 19th century, the concept of intelligence as idely debated. David Wechsler vieed intelligence as a multidimensional response construct, one that manifests itself in many forms, not only as a global entity, but as a collection of specific abilities. Weschler concluded that intelligence is the capacity of the individual to act purposefully, to think rationally and deal effectively ith his environment (Weschler, 2002). Le Carret and colleagues (2003) carried out research into ho educational levels influence visual orking memory using the BVRT on elderly individuals. They found that higher levels of intelligence resulted in better performance but as a result of better executive abilities rather than visual discrimination skills. They concluded that higher levels of education meant individuals ere able to use more efficient strategies. The Normative standard section of the BVRT states that performance on all three administrations for the three forms correlates substantially ith intelligence level (Benton Sivan, 1992). Correlation coefficients for the stated age groups claim to average from 0.46 to All published normative data collected and explained in the manual are described on the basis of the relationships beteen intellectual level and chronological age ith BVRT performance. Method tionale The aim of this study is to gain a set of normative data for performance on the BVRT for individuals aged beteen 18 and 30 years of age. Currently no normative data exists for BVRT performance for this particular age group. The BVRT is an essential instrument in clinical research hen studying patients ith brain disease or brain damage. Hoever, for an accurate assessment of an individual s BVRT performance, a set of normative data for that specific age range for comparison must exist. Furthermore, this study aims to look at the correlation beteen cognitive functioning (as tested by the WAIS III and IQ s) and BVRT scores for this age group, to determine if a significant relationship exists beteen IQ and BVRT performance as has been observed in other age groups previously studied. Materials Benton Visual Retention Test Benton designed his first edition of the BVRT in 1946 (Benton, 1946). After revieing limitations and eaknesses, revies have been made, a first revision as made in 1955 (Benton, 1955), and further revisions in 1963 (Benton, 1963) and 1974 (Benton, 1974). Each time, a ne set of normative data have been produced for various age groups. Each revision has enhanced the use of the BVRT in clinical practice and research. The BVRT has 3 similar forms of task C, D and E, each consisting of 10 designs containing one or more figures. There are 4 methods of administration A, B, C and D. Clinical investigators have devised novel administrations of the BVRT to anser specific research questions. For the purpose of this study, administrations A, B and D ill be used to see ho healthy year olds perform ith time constrictions and delays outlined belo. Administration A Participant vies each design for 10 seconds and then immediately reproduces the design from memory. Administration B (serves as a comparison for the amount of time needed to process each stimulus). Participant vies each design for 5 seconds and immediately reproduces the design form memory. Administration D (requires examinees to retain the WebmedCentral > Original Articles Page 5 of 27

6 Donloaded from on 24-Dec-2011, 10:01:46 AM percept for a brief period of time). Participant vies each design for 10 seconds, after a delay of 15 seconds, is then asked to reproduce design from memory. WAIS III David Wechsler designed the first edition of the Weschler Adult Intelligence Scale in 1939 (Weschler, 1939). Weschler observed certain attributes hich can account for the overall variance of intelligence; these include basic human motivations, attitudes and personality traits, such as persistence, goal aareness and enthusiasm. The WAIS reflects an individual s overall ability, here the subtests look at such skills as abstract reasoning, perceptual skills, verbal skills and speed processes. Since 1939, revisions have been made, to allo for changes in social and culture era, the WAIS is no in its third edition (Weschler, 2002). The Wechsler Adult Intelligence Scale consists of 14 subtests. When restricted by time, it is possible to follo the short form WAIS III, hich still remains far superior to many other intelligence scales available (Weschler, 2002). For the purpose of this study the short form of WAIS III ill be used. The scoring process involves the conversion of ra scores into scaled scores hich provide 3 levels of IQ; Performance IQ, Verbal IQ and Full Scale IQ. Hospital Anxiety and Depression Scale The HADS is a self screening questionnaire first designed in 1983 by Snaith and Zigmond, based on an item analysis of a longer list of items given to patients attending an out-patient clinic (Snaith & Zigmond, 1983). The Anxiety scale as based on feelings of tension, tendency to unnecessarily orry and apprehensive anticipation. The Depression Scale as based on enjoyment of usual activities, retention of a sense of humour, depressed mood and optimistic attitude. The HADS is a Questionnaire consisting of 14 questions, 7 for anxiety and 7 for depression, each scoring 0-3 points per item. In this study the HADS is used as a screening technique in order to gain a cognitive profile of the sample population. For this reason the aim is to use participants that score at either a normal (0-7), mild (7-10) or moderate (11-14) level for both Anxiety and Depression. A score of 15 or higher suggests possible presence of a mood disorder hich may interfere ith the rest of the study. Experimental hypotheses Based on existing research the hypotheses for this study include: H1 There ill be a significant relationship beteen Full IQ and Total Errors score and Total Correct responses on the BVRT. H2 There ill be a significant relationship beteen Full IQ and Total Errors score and Total Correct responses across the three administrations A, B and D. H3 Both Performance IQ and Verbal IQ ill be significantly correlated ith Total Errors score and Total Correct responses. H4 There ill be a significant relationship beteen Total Errors Score and Total Correct responses and Anxiety and Depression score on the HADS. Study design This study ill look at the interactions beteen Performance on the BVRT and IQ Levels. A Pearson product-moment correlation coefficient as used to analyse the relationship beteen Total Errors score, and Total Correct responses under the 3 administrations A,B and D of the BVRT, together ith: Full IQ Performance IQ Verbal IQ A Pearson product-moment correlation coefficient analysed the relationship beteen Total Errors score, and Total Correct responses under the 3 administrations of the BVRT (A, B and D) and Depression and Anxiety scores on the HADS. In order to determine if age or gender had any significant influence on the data collected, a 3 x 2 unrelated ANOVA as implemented to investigate a significant difference in performance on the BVRT beteen genders and age groups. The first Independent variable (IV) as gender, hich had to levels; Males and Females. The second independent variable as age group, and as split into 3 levels; (mode = 19, median = 19), (mode = 21, median = 21) and (mode = 26, median = 26). The dependent variables ere Total Errors score and Total Correct responses. Participants A sample of 50 undergraduate Bournemouth University students took part in the study; they ere recruited on a volunteer basis. 14 male and 36 female first, second and third year students took part in the study. The age range as beteen years old, ith the mean age being 22. The sample as recruited via s to students, and through the university study program SONA, this allos first and second year students to vie the available studies in hich they can participate ith the incentive of gaining research experience hich is mandatory for their university course. All participants ere British Citizens living in the United Kingdom ith English as their first language. All participants came from similar socio-economic and educational backgrounds. All participants ere psychologically assessed using the HADS self-screening questionnaire to ensure they ere ithin the healthy range. WebmedCentral > Original Articles Page 6 of 27

7 Donloaded from on 24-Dec-2011, 10:01:46 AM Procedure Prior to the commencement of the study, ethics approval as obtained from the Bournemouth University Research & Ethics Committee ( ) to clarify that the study adhered to all ethical guidelines. To computer laboratories at Bournemouth University ere booked for 10 sessions, participants ere seen for 2 hour sessions over a period of 2 eeks; to sessions each Monday, one on each Tuesday, one on each Wednesday and one on each Thursday. Five Participants took part in each session alloing for confounding variables to be controlled and for the efficiency of the running of the experiment ithin the time allocated. Each participant entered the 1st Lab and sat at individual desks separated by partitions to ensure there ere no interactions beteen participants. In front of each participant as a study information sheet, participant information sheet, consent Form, HADS questionnaire, WAIS response booklet and 3 BVRT response booklets. On commencement of the study the experimenter explained in full hat the study involved, the order in hich it ould be carried out and the aim of the research. Participants ere asked to read the study information sheet, and given the opportunity to ask any questions or to ithdra themselves from the study. Once everything as made clear, participants ere asked to fill in the Participant Information sheet and read and sign the Consent Form. When all forms ere completed, they ere then asked to turn to the HADS Questionnaire. The experimenter instructed participants to read each statement and report their immediate response to each item ithout spending too much time making long thought-out replies. All completed forms ere then collected and the first test as ready to be administered. The BVRT as displayed on the projector screen at the front of the lab. The procedure and requirements of the test ere explained using the standardised explanation for each administration. The participants completed the three administrations hich ere timed using a stopatch by the experimenter. Once the BVRT as completed the three response booklets ere then collected in. The WAIS III Short Form Administration as then explained to the participants using the standardised explanation in the WAIS III Administration Manual. Eight subtests ere carried out en masse to participants, the to remaining subtests required one on one examination and each participant as called into the second lab one at a time to carry them out. Once all participants had completed all tests, they ere fully debriefed on every aspect of the study and again offered the opportunity to ask any questions or ithdra themselves and any information they had given from the study. They ere also informed that results ere available for collection from the researchers. Results Statistics 50 participants took part in the study; their full IQ s ranged from 90 to 155 ith an average of 118 and standard deviation of The average of Total Correct responses (on all 3 administrations) ere ith a standard deviation of 4.36, the average total number of errors made as 16.80, ith a standard deviation of The average score of the HADS as 3.94 for Depression ith a standard deviation of 3.59 and 3.88 for Anxiety ith a standard deviation of SPSS 18 as used for statistical analysis of the data (Illustrations 1-4). Hypothesis 1 A Pearson product-moment correlation coefficient as computed to assess the relationship beteen Full IQ and Total Errors score and Total Correct responses on the BVRT (Illustration 4). There as a significant correlation beteen Full IQ and Total Correct responses, r = 0.001, n = 50, p = There as a significant correlation beteen Full IQ and Total of Errors Score, r = 0.000, n = 50, p = Both Variables; Total Correct responses and Total Errors Score demonstrate a strong relationship hich is significant at a level of p The scatter plot demonstrates a steep decline in the Total Errors score as individual s Full IQ increases, illustrating a strong negative correlation. Also, a fe anomalies can be seen ithin the error scores, 7 participants error scores appear to be significantly larger compared to the rest of the data group. The Total Correct responses incline at a milder rate as Full IQ increases and remain more consistent; a strong positive correlation is clearly demonstrated. Hypothesis 2 A Pearson product-moment correlation coefficient as computed to assess the relationship beteen Full IQ and Total Errors score and Total Correct responses across the three administrations A, B and D: There as a significant correlation beteen Full IQ and Error score Administration A (mean = 5.06), r = 0.006, n = 50, p = Error score Administration B (mean = 7.00), r = 0.003, n = 50, p = Error score Administration D (mean = 4.74), r = 0.009, WebmedCentral > Original Articles Page 7 of 27

8 Donloaded from on 24-Dec-2011, 10:01:46 AM n = 50, p = Correct responses Administration D (mean = 7.36), r = 0.005, n = 50, p =.391 These relationships are significant at a level of p Correct responses Administration A (mean = 7.14), r = 0.032, n = 50, p =.303 Correct responses Administration B (mean = 5.84), r = 0.026, n = 50, p =.315 These correlations are significant at a p A scatter plot summarises these results (Illustration 5). Illustration 6 demonstrates the spread of correct responses across the 3 administrations. It is clear that for administrations A, B and D, correct responses are significantly positively correlated ith Full IQ scores. Similarly, Illustration 7 demonstrates ho administrations A, B and D error scores are significantly negatively correlated ith Full IQ. Hypothesis 3 A Pearson product-moment correlation coefficient as computed to assess the relationship beteen both Performance IQ and Verbal IQ and Total Errors score and Total Correct responses. Performance IQ as significantly correlated ith Total Correct responses, r = 0.001, n = 50, p =.457. Performance IQ as also significantly correlated ith Total Errors score, r = 0.001, n = 50, p = Verbal IQ as also significantly correlated ith Totals r of Errors score, r = 0.003, n = 50, p = These relationships are significant at a level of p In Illustration 8, the relationships are demonstrated further through the gradient of the regression lines. Again the spread of Total Correct responses is more evenly spread in comparison to Total Error scores for both VIQ and PIQ. For PIQ the regression lines appear more closely related (Illustration 8). Hypothesis 4 A Pearson product-moment correlation coefficient as computed to assess the relationship beteen Anxiety and Depression scores on the HADS and Total Correct responses, and Total Errors score on the BVRT. No significant correlations ere found beteen Anxiety and Correct response score, r = 0.434, n = 50, p = , or beteen Anxiety and Errors score, r = 0.435, n = 50, p =.113. No significant correlations ere found beteen Depression and Total Correct responses, r = 0.112, n = 50, p = 0.228, or beteen Depression and Total Errors score, r = 0.116, n = 50, p = x 2 unrelated ANOVA for gender and age A 3 x 2 unrelated ANOVA as carried out to identify any significant effects age and gender had on correct responses. The first IV as Age, there ere 3 levels; (mean correct responses = 19.32), (21.33) and (21.4). The second IV as Gender hich had 2 levels; male (22.21) and female (19.61). The main affects for Gender and Age ere not significant. A 3 x 2 unrelated ANOVA as carried out to identify any significant effects age and gender had on number of errors made. The first IV as Age, there ere 3 levels; (mean error score = 18.84), (15.06) and (14.30). The second IV as Gender hich had 2 levels; male (11.78) and female (18.75). The main effects for Age ere not significant. Hoever the main effects for Gender ere significant; F(1,50) = 4.178, P< 0.05 (P=0.047). Although a significant difference has been found, the sample collected only represented 14 males compared to 36 females. This questions the validity of these findings, as the sample may not represent a fair number of each gender. Summary BVRT results Illustrations 10-12, demonstrate the expected BVRT performance scores for year old individuals depending on IQ score grouping, for each administration A, B and D). The ay in hich they are tabularised are based upon ho existing Normative data are recorded in the BVRT Manual (Benton Sivan, 1992). Illustration 13 summarises FIQ, Correct and Error scores of the BVRT for each participant. Discussion Firstly, the results obtained from the study provide support for Hypothesis 1. There as a significant positive correlation beteen IQ Score and Total Correct Responses on the BVRT. There as also a significant negative correlation beteen IQ Score and Total Errors score on the BVRT. By correlating the results of the to tests in a scatter plot (Illustration 6), the strength of relationships of these significant correlations can be further understood. The Linear Regression line for errors shos a steeper decline in comparison to the incline in correct responses, suggesting that there may be a slightly stronger relationship beteen IQ and errors made than IQ and correct responses. These results strongly suggest that IQ level is in some ay related to our visual perception, visual memory and visuo-constructive abilities. A loer IQ suggests that the individual s ability to perform ell in such tests is eaker. Based on this study, Hypothesis 1 as accepted. Hypothesis 2 predicted that IQ ould be significantly correlated ith Total Correct responses and Total Errors made across all administrations of the BVRT. The data collected supported this Hypothesis, and positive correlations ere found beteen IQ and Total WebmedCentral > Original Articles Page 8 of 27

9 Donloaded from on 24-Dec-2011, 10:01:46 AM Correct responses for A, B and D, and negative correlations beteen IQ and Total Errors score made on A, B and D. Illustrations 6 and 7 help to further understand the relationships identified. From the linear regression lines it is clear that all administrations have strong relationships ith IQ Level. For both Errors and Correct Scores the line shos a steeper decline (in errors), and more gentle incline (in correct responses) for administration B. This ould suggest that the participants had more difficulty in reconstructing images hen they ere only able to vie the image for 5 seconds prior to draing it. Statistical analysis revealed that although they ere still significant at a level of p It as expected that both Verbal IQ (VIQ) and Performance IQ (PIQ) ould be significantly correlated ith the Total Correct responses and Total Errors score on the BVRT. Again, significant correlations ere found, both PIQ and VIQ as positively correlated ith Total Correct responses, and negatively correlated ith the Total Errors made. Illustrations 8 and 9 demonstrate the strength of the relationships through the gradient of the regression lines. Another observation hich as very interesting as the mean average of participants VIQ s (110.2) as much loer than the mean average of participants PIQ s (127.4). VIQ is assessed by 7 of the 14 subsections of the WAIS, it is indicative of an individual s ability to ork ith abstract symbols, verbal memory skills, and fluency abilities. PIQ is assessed by the other 7 subsections, and is indicative of an individual s ability to ork ith concrete situations, to integrate perceptual stimuli ith motor responses and visuo-spatial ability. As visuo-spatial ability is also part of hat is being assessed in the BVRT, this could explain the strong relationship identified. In clinical settings if PIQ is significantly higher than VIQ, it may be suggestive of a learning disability, autism or mental retardation, they may also have difficulty understanding auditory directions and putting them into practice. In the case of the current study it may be a reflection of their educational backgrounds or degree type. On the basis of these results Hypothesis 3 as accepted. Finally, the strength of relationship beteen Anxiety and Depression Scores on the HADS and Total Correct responses and Total Error scores on the BVRT as tested. There ere no significant correlations beteen Anxiety and Depression Scores ith performance on the BVRT. Of the 50 participants only 7 ere classified as above normal levels of Depression and only 2 above Mild levels. Even less scored above Normal levels of Anxiety, 2 ere classified as Mild and 3 Moderate. Hoever, as the HADS as being used to gain a Cognitive Profile of the sample, it as the initial aim to only have participants scoring in lo levels of Anxiety and Depression to ensure that this did not interfere ith their performance. Of the fe that did score slightly above healthy levels, there as no significant effect on their performance on the BVRT. Based on this evidence the Null Hypothesis as retained and the Alternative Hypothesis 4 as rejected. Although a significant difference as found beteen males and females performance, the sample collected only represented 14 males compared to 36 females. This may question the validity of these findings, as the sample may not be representative of each gender and so it is not possible to further generalise this to the population. When looking at the BVRT results it is clear that the most common errors that ere made ere Distortion Errors, these are inaccurate reproductions of a single figure of a design. On average participants made beteen 2 to 3 Distortion errors on administrations A and D, for administration B the average as 3-4 errors. The second most common errors ere Omission and Addition Errors, an omission error can be classified by a single figure of a Design being completely omitted or no recognisable attempt as made to reconstruct the figure. An Addition Error in contrast ould be hen an additional figure present in the reconstructed design hich could not be scored as a Perseveration or Distortion Error. On average participants made beteen 1 and 2 Omission errors for administration A, B and D. Misplacements and Rotations ere the next most commonly made errors, Size and Perseverations errors ere far less common. Administration B resulted in the least amount of correct responses and the most amounts of errors made. Almost 100 more errors in total for the 50 participants ere made in administration B as compared to administration A, and over 100 in comparison to administration D. Of the 50 participants, irrespective of IQ, an average of 7-8 correct scores for both administrations A and D as found as compared to 5-6 for administration B. These findings further indicate that the sample population of 18 to 30 year old individuals struggled most hen only vieing the image for a brief period of time, suggesting that to fully absorb an image 5 seconds is not adequate. By looking at the standard deviation (SD) e can see ho the data as distributed across the sample population. The data appears to be equally distributed across Administrations for correct responses, ith the largest being 2.02 for administration D. Total Correct WebmedCentral > Original Articles Page 9 of 27

10 Donloaded from on 24-Dec-2011, 10:01:46 AM responses has a standard deviation of For Error scores hoever the distribution seems more idely spread, for administration A the SD = 3.55, for B = 4.23 and D = 4.73, overall error scores had an SD of This suggests that there may be certain factors hich influence individual s susceptibility to errors rather than just the administration of the test. For Total Errors score, participants ranged from 1 (ith an IQ of 125) and 41(ith an IQ of 95). During the study significant correlations ere identified beteen Full Scale IQ s and performance on the BVRT for administrations A, B and D. This adds further support for a vast amount of existing literature on this relationship. Carret and colleagues (2003) carried out a study to investigate ho educational levels influence visual orking memory using the BVRT on elderly individuals. They found that higher levels of intelligence did result in better performance; these findings coincide ith the data collected in the current study, hich demonstrates the same findings for a younger age group of 18 to 30 year olds. Emdad and Sondegaard (2006) looked at intelligence levels and BVRT performance on Post Traumatic Stress Disorder (PTSD) patients. They found that despite comparable differences in levels of intelligence, this had no significant relationship ith performance on the BVRT on the control group. Hoever ith the PSTD group, they found deficits in short term memory and non-verbal memory, these ere directly related to intelligence. Emdad and Sondegaard s study suggest that intelligence only influences performance if it is related to the specific deficits identified by BVRT performance. Whereas the current study provides convincing evidence to suggest that in healthy year olds, significant correlations could be found beteen IQ and BVRT performance. The participants used in Emdad and Sondegaard s study ere of an older age group and only 20 control participants took part, this might explain the difference in findings. Ellis and colleagues (2008) found that mild anxiety as associated ith better cognition, hen severity increased, performance ent don. This study found no correlation beteen anxiety score on the Hospital Anxiety and Depression Scale (HADS) and performance on the BVRT. Hoever, 45 of the 50 participants in the study all scored at a normal healthy level and no participants scored above a moderate level. Therefore it cannot be concluded from this study that Anxiety levels do not influence BVRT performance. The Normative standards for clinical use of administration A, as based on Benton (1963) looking at over 600 individuals mainly in and out patients of a hospital in Ioa. According to this existing data, an individual aged beteen 15 and 49 ith an IQ of should obtain a correct score of 8 on administration A and ith an IQ of 110 or higher should obtain a correct score of 9. According to the data collected in the current study, an individual ith an IQ score of 110 or above should obtain a correct score of 7 or 8. Furthermore, the existing data suggests an individual hose IQ is beteen 90 and 94 ill have an error score of 4, from an error score of 3, an error score of 2 and 110 and above an error score of 1. The data in the current study has found slightly different margins, an individual hose IQ is 95 or belo may have an error score of 10, beteen an error score of 5 or 6, and 111 or higher an error score of beteen 3 and 5. The slight difference in data could be due to the existing data being quite dated, in current times people may be educated to a higher level hich might affect the correct or error scores. The Normative standards for individuals aged 60 and younger for administration B, according to the manual, are based on performance in administration A, minus 1 point for correct scores. These data ere based on the research of Von Kerekjarto (1961). The relation for error scores beteen the to administrations has not yet been reported. A similar pattern as found in this study, correct scores ere on average one point less for each IQ range. What is interesting to observe in the present study is that the number of errors made increases by a larger amount. For individuals hose IQ s are beteen 96 and 110, error score is estimated to be 7 or 8 compared to 5 or 6 for A, and 95 and belo, is 13 or 14 compared to 10. Data collected lead to the conclusion that normal adults aged 60 years and younger perform as ell in administration D as they do on administration A. Administration D involves a short delay of 15 seconds after vieing an image for 10 seconds, before constructing the design on paper; this meant retaining an image for a brief period of time. This as developed in order to identify participants ith brain disease ho ould perform even normally or mildly defective on other administrations. Vakil and colleagues (1989) found correlations of 0.54 for correct scores and 0.65 for error scores and so differences in performance, in either direction, may be encountered. Severe impairments in the delay conditions suggest a defect in memory storage capacity; hoever superior performance has not yet been examined. It may be that the delay condition allos individuals time to fully construct the design in their mind, hich ould be beneficial for someone ho has sloed information processing abilities. As of yet, data collected for administration D has not been WebmedCentral > Original Articles Page 10 of 27

11 Donloaded from on 24-Dec-2011, 10:01:46 AM adequate for routine clinical use. The present study produced findings that represent a similar pattern to that found in the existing literature, hat is interesting to note is a total of 128 Distortion errors for the 50 participants ere made in administration A, compared to 107 in administration D. This is a significantly loer sum suggesting the delay resulted in feer distortion errors, still no other significant differences ere found for any other types of errors. Methodological issues According to the Handbook of normative data for neuropsychological assessment, (Mitrushina & Boone 2005, p.400) 7 key criteria ere deemed to be adequate for evaluating the studies on the BVRT. These include Composition Description and Age Intervals, Educational Levels, IQ levels, Specification of Test Version and Data Reporting, all of hich have been clarified and controlled for. The 7th criterion is number of participants. The results of the present study may be restricted by the number of participants that ere used in the sample. Although 50 participants is considered a desirable sample size, the smaller the sample the more influenced by individual differences it may be, therefore 50 may not be a representative depiction of the entire population of 18 to 30 year old individuals. The results obtained ere significant; it may be beneficial to repeat the study on a larger sample hich may have more validity hen generalising to the larger population. Also only 14 of the participants ere males and 36 ere females, in addition 25 of the participants ere beteen 18 and 20 and the other 25 ranged from A more varied sample of ages and equally divided sample of males and females may offer further validity. The results of the present study offer further support for a large amount of existing literature, and so in future research the same findings ould be expected. Another possible limitation may be that the study as carried out on groups of 5 participants at a time. Although they ere separated by partitions the presence of others may have interfered ith their performance on the tasks. For example, hen filling out the Hospital Anxiety and Depression Scale Questionnaire they may have been orried that others may see ho they ere filling it in and not have been honest. Also as the HADS is a self-screening questionnaire, this may have also meant that their ansers ere dishonest possibly due to a fello student carrying out the study despite full confidentiality of the data. Hoever, research has indicated that the HADS is valid as a screening technique for cognitive profiles. When completing the WAIS III, they may not have paid their full attention to the task at hand, and possibly been discouraged if others ere ansering questions more promptly and easily. In future research here time constraints are not an issue, the study could be carried out on an individual basis, therefore eliminating the distraction of the presence of others. The study as particularly time consuming, thus may have lead to participants experiencing boredom and fatigue, this may have contributed to the variation in some levels of the data. This could be the cause of larger standard deviations in some parts of the data, such as the vast range in IQ scores or Error scores on the BVRT. Timing as an issue for both the researcher and participants, ho ere all also students under pressure from deadlines and vast orkloads. To spread the study over a number of days hen the participants are not in a time of increased stress and orkload, ith distractions on their mind, this may add further validity to the study. Implications for future research The development of this set of normative data for this ne age group, 18 to 30 year olds, ill greatly aid in the advance of the use of the BVRT as an instrument in clinical fields. The BVRT can no be used on brain damaged patients or patients suffering from brain diseases ithin this younger age group to accurately measure the extent of damage to their visual perception, visual memory and visuo-constructive abilities. Future research can no accurately assess performance of neuro-psychologically impaired individuals ithin this ne age group, suffering from such disorders as Post Traumatic Stress and Schizophrenia, on the BVRT, by comparing to this ne set of normative data. This can then be used for comparison against that of existing literature on other age groups to see ho age may affect the extent of impairment of these cognitive skills. In addition, individuals ith learning disabilities and ADHD can no be assessed to investigate the possibilities of progress or decline ith age into early adulthood, no that a set of normative data exists for this age range. Conclusion In conclusion to this study a ne set of Normative Data has been collected for the ne age group of year olds. With this development in BVRT research, clinical applications can benefit from these findings hen looking at patient s ith brain damage or those suffering from a brain disease ithin this age group. The findings are consistent ith the normative standards stated in the BVRT fifth edition manual for WebmedCentral > Original Articles Page 11 of 27