Discriminating between simulated malingering and closed head injury on the Wechsler memory scale-revised

We tested the hypothesis that malingering is distinguished by poorer performance on recognition relative to recall tasks by evaluating the ability of discriminant functions to distinguish between 89 subjects simulating malingering and 44 subjects with a history of closed head injury (CHI) on the Wechsler Memory Scale - Revised (WMS-R). Functions with good accuracy in discriminating between simulated malingerers and controls in prior studies did not have adequate specificity when applied to the CHI group. A newly derived discriminant function achieved overall classification accuracy of 79% for the malingering versus CHI groups on cross-validation, with 79% sensitivity (true positives for malingering) and 80% specificity (true negatives for closed head injured). A complex performance pattern on seven WMS-R subtests distinguished malingering subjects from those with CHI, but did not support the recognition versus recall hypothesis. The malingering pattern involved: (a) power performance on two relatively (but inconspicuously) easy tasks dependent on immediate recall (Visual Reproduction I and Visual Memory Span); (b) better performance on two relatively (but inconspicuously) easy tasks dependent on immediate recall (Visual Paired Associates I and Digit Span); (c) poorer performance on two relatively difficult delayed tasks (Logical Memory II and Visual Paired Associates II); and (d) better performance on another difficult task involving delayed recall (Visual Reproduction II).     

Verbal vs. visual categories on the Wechsler memory scale - revised: How meaningful a distinction?

This study investigated whether the a priori classification of Wechsler Memory Scale-Revised (WMS-R) subtests into separate Verbal and Visual categories is warranted. Correlational and hierarchial clustering analyses found that (a) memory test performance correlated significantly with performance on subtests of Form II of the Luria-Nebraska Neuropsychological Battery (LNNB-II) that measure substrates of particular memory processes; and (b) subtests that appeared a priori to involve verbal skills clustered separately from those that appeared to involve nonverbal (visual) skills. However, the WMS-R Visual Paired Associates subtest did not cluster with the nonverbal scales as expected, and the LNNB-II Memory Scale appeared to be predominantly a test of verbal memory. Practical consequences of these findings were discussed.     

The impact of constructional impairment on the WMS-R visual reproduction subtests

The present study investigated the impact of constructional impairment on performance on the WMS-R Visual Reproduction subtests that measure memory for visual material. Thirteen subjects with constructional impairment had lower scores on the immediate and half-hour delayed Visual Reproduction subtests, relative to a cognitively comparable group of subjects without constructional impairment. However, the two groups did not differ with respect to their performance on the WMS-R Logical Memory subtests, which measure verbal memory. The implications of these modality specific findings among subjects with constructional impairment are discussed, and recommendations for clinicians who utilize the WMS-R are provided.     

Cognitive dysfunction and change in multiple sclerosis

A cross-sectional study of 60 multiple sclerosis outpatients assessed neuropsychological variables in relation to age, duration of disease, and degree of disability. The test battery included subtests of the WAIS (Vocabulary, Similarities, and Digit Span);the Raven matrices; and memory tests (Wechsler Paired Associates, Benton Visual Retention). Results showed that cognitive functioning of MS patients varies considerably. There is a general mild decline that affects abstract reasoning and memory as the disease progresses. These deficits are usually not sufficient to impair occupational or social functioning. In addition, there is spotty deterioration in certain cognitive functions for some patients (17%). Only a small subsample (6.7%), however, showed global deterioration significant enough to be highlighted by an Index of Dementia that was developed for this investigation.     

Factor analysis of the WMS-R and the WAIS.

A principal components factor analysis of the Wechsler Memory Scale-Revised (WMS-R) and Wechsler Adult Intelligence Scale (WAIS) was performed on 133 patients referred for neuropsychological assessment al a university medical center. Six factors were selected according to the Scree test, percentage of variance extracted, and the meaningfulness of the factors. The factors were labelled as follows: Perceptual Organization, Verbal Comprehension, Attention/Concentration, Complex Verbal Memory, Verbal Paired-Associate Memory, and Visual Paired Associate Memory. The Figurai Memory and Visual Reproduction I & II failed to emerge as a factor separate from the Performance subtests of the WAIS. Two verbal memory factors were found apart from the Verbal subtests of the WAIS.     

Russells revised wechsler memory scale in the evaluation of dementia

Matched 31 elderly normals and 25 patients with suspected Alzheimer's disease for age and education and administered the Revised Wechsler Memory Scale (WMS-R). The patient group performed significantly less well than the control group on all WMS-R subtests. A bimodal distribution of Percent Retained scores was noted in the patient group, but not in the control group. Results are discussed with respect to the clinical utility of the WMS-R as a memory screening procedure.     

Memory and learning performances in POW survivors with history of malnutrition and combat veteran controls.

Former prisoners of war (POWs) with histories of malnutrition and body wasting were compared on standardized measures of memory and learning with POW survivors who sustained less confinement body weight loss and combat veterans of similar ages and military assignments. Results showed that POWs who sustained the greatest degree of trauma-induced weight loss, or that exceeding 35% of their precaptivity body weights, performed significantly worse on four of the five Wechsler Memory Scale /3-Revised (WMS-R) indices, showed more rapid rates of forgetting on the Visual Reproduction test, and exhibited slower acquisition rates and less sophisticated mastery of the learning materials on a modified version of the Rey Auditory Verbal Learning Test (AVLT). Given their relatively intact performances on measures of general intelligence and attention-concentration, the POWs with a history of severe malnutrition appeared to evidence a pattern of cognitive limitations qualitatively similar to that associated with alcoholic Korsakoff's syndrome.     

The East Boston Memory Test: A clinical screening measure for memory impairment in the elderly

Comparisons between the East Boston Memory Test (EBMT), a brief verbal memory measure used in epidemiological studies with dementia, selected Wechsler Memory Scale-Revised (WMS-R) subtests, and the Mini-Mental State Examination (MMSE) were investigated with 23 geriatric patients diagnosed with dementia. Significant correlations between the EMBT and WMS-R verbal subtests were predicted and occurred (r = .42 to .64). A five minute EBMT recall correlated most highly with the WMS-R Logical Memory subtests. The sensitivity of the EBMT in detecting cognitive impairment was investigated and compared with the sensitivity of the MMSE. The EBMT correctly classified 78% of subjects, compared to a 70% correct classification rate with the MMSE. Implications of these findings and suggestions for future research directions are discussed. © 1996 John Wiley & Sons, Inc.     

Differential declines in cognitive function with aging: The possible role of health status

The differential decline of memory (Wechsler Memory Scale Logical Memory and Visual Reproduction subtests) and “executive” cognitive skills (Halstead‐Reitan Category Test) and their relationship to health status were examined in this cross‐sectional study of 154 elderly individuals. Age‐related differences in memory were observed in both healthy and unhealthy participants. No overall age‐related differences were noted on the Category Test. Performance on this test, however, was related to health status, although memory performance was not.     

Diagnostic efficiency and material specificity of the Warrington Recognition Memory Test: a collaborative multisite investigation.

Two studies examined the Warrington Recognition Memory Test (RMT) discrepancy index (Words-Faces) in a large sample of patients heterogeneous with respect to age, education, gender, and neurological diagnosis. In Study 1 (N = 504) we used cutoffs from the Words-Faces discrepancy scores derived from Warrington's original validation sample to attempt to accurately classify patients with left, right, or diffuse brain damage. Sensitivity for left hemisphere patients (Faces > Words) was 10% with a specificity of 88%, whereas sensitivity for right hemisphere patients (Words > Faces) was 48% with a specificity of 86%. For patients with diffuse brain damage (Words = Faces) sensitivity was 69% and specificity was 38%. In Study 2 (N = 263), we examined the relationship between the Words-Faces discrepancy score and Wechsler Memory Scale-Revised (WMS-R; Wechsler, 1981) Logical Memory and Visual Reproduction subtests. Contrary to predictions, patients with Words > Faces performed better on both WMS-R subtests; the Faces > Words discrepancy was not related to Visual Reproduction performance. Potential reasons for these negative findings are discussed, as well as cautions for future RMT discrepancy index use.     

Normal aging increases cognitive heterogeneity: Analysis of dispersion in WAIS-III scores across age

Individual differences in cognitive decline during normal aging need further delineation. The purpose of this study was to find the score dispersions in the WAIS-III subtests at different ages. Norms presented in the Administration and Scoring Manual [Wechsler, D. (1997). WAIS-III: Administration and scoring manual. San Antonio: The Psychological Corporation] were used. The WAIS-III was standardized and normalized using 2450 American adults divided into 13 age ranges and 4 education groups. Means and standard deviations for the different WAIS-III subtests were deduced and the ratio Percentage of the mean="(standard deviation/mean)x100" was calculated. It was hypothesized that during normal aging, whereas mean scores decrease, score dispersions increase, pointing to an increased heterogeneity in intellectual abilities in older individuals. In all subtests, except Digit Span, it was found that score dispersions indeed increased during aging. However, in some subtests, increase in dispersion was less than 20% (Block Design, Object Assembly, and Information), whereas in others, increase in dispersion was over 200% (Matrix Reasoning, L-N Sequencing, Digit-Symbol, Picture Completion, and Picture Arrangement). It was proposed that cognitive heterogeneity during normal aging is related to those abilities measured with these latter subtests, basically, executive functions, attention, and selected non-verbal abilities. In other abilities (e.g., visuoconstructive abilities and fund of general information), normal aging is associated with a more homogenous pattern of decline.     

The relationship of age to performance on the Luria-Nebraska Neuropsychological Battery

The effect of age upon the Luria-Nebraska Neuropsychological Battery (LNNB) was studied by administering the LNNB and the Wechsler Adult Intelligence Scale to three groups of subjects: A group aged 17-30, a group aged 50-55, and a group aged 65 and older. No subject had any history of brain pathology or psychotic emotional disturbance. Two of the Luria-Nebraska subtests, the Motor and Visual, showed a significant sex-effect in that males performed better than females. Age was related significantly to performance on 11 of 16 Luria Nebraska subscales; older subjects rather consistently showed poorer performance than younger subjects. When intelligence (i.e., Wechsler IQs) and education were controlled statistically, partial correlations still revealed that age had significant effects upon 13 of 16 Luria-Nebraska subscales. These results closely parallel earlier data that concern age-effects on the Luria-Nebraska Battery.     

认知伪装甄别测验的编制和信效度分析

目的：编制一套甄别认知伪装的心理测验，并检验它的信效度。方法：按照Rogers提出的伪装甄别策略，编制了两个迫选式再认分测验一数字迫选测验和图符迫选测验，每个分测验含30个条目。264名正常人、33名脑损害病人和125名可疑伪装的鉴定者完成认知伪装甄别测验．其中303名被试接受华文认知能力量表测试、297名被试接受多维记忆评估量表测试。结果：数字迫选测验和阿符迫选测验的重测相关系数分别为0．603和0．571。数字迫选测验的信度系数在0．749—0．888之间，图符迫选测验的信度系数在0．753—0．872之间，全量表的信度系数为0．843—0．936。认知伪装甄别测验成绩与华文认知能力量表和多维记忆评估量表各分测验分数有显著性相关，相关值在0．308—0．608之间。正常人不同年龄组的测验成绩有明显的差异，正常组、脑损害病人组和鉴定组的测验成绩和成绩曲线有明显的不同。结论：认知伪装甄别测验具有较好的信度和效度．可以作为认知伪装的甄别工具。     

Subcortical hyperintensities impact cognitive function among a select subset of healthy elderly.

Previous studies have examined the impact of subcortical hyperintensities (SH), a proxy measure of cerebrovascular disease, on the cognitive abilities of otherwise healthy older adults. However, there remains a limited understanding as to what extent this MRI marker of pathological processes explains the decline in specific cognitive functions that occur nearly ubiquitously with advanced age, especially in relation to other age-related imaging markers. In the present study we compared cognitive abilities between a sample of 53 older healthy adults (age range=50-79) and a sample of 53 younger adults (age range=21-40). As expected, the older group performed significantly worse on most cognitive measures compared to the younger group. Frontal volume and total grey matter volume were also significantly reduced among the older individuals compared to the younger individuals. SH volume was consistently associated with cognitive function in older adults, though, this relationship was evident only for a relatively small subset of older individuals with the most severe SH. These data suggest that the relationship between SH and cognition in the elderly is driven by a subset of individuals who may be in the earliest stages of vascular cognitive impairment. Further, the findings suggest that cognitive aging is largely determined by factors other than SH for most older adults.     

Rapid eye movement density is reduced in the normal elderly

STUDY OBJECTIVES: While there is general agreement on the age changes in non-rapid eye movement sleep, there is conflicting evidence on whether eye movement density (EMD) in rapid eye movement sleep is affected by aging. We therefore performed computer measurement of EMD in young and elderly normal subjects. DESIGN: Sleep electroencephalogram and electrooculogram were recorded in each subject on 4 nonconsecutive baseline nights. Eye movement density in the elderly subjects was compared to that in young adults. SETTING: A sleep research laboratory with 4 separate bedrooms. INTERVENTIONS: Not applicable. PARTICIPANTS: Subjects were 19 young normal adults and 19 elderly normal adults. MEASUREMENTS AND RESULTS: Digitized electrooculograms were analyzed with the extensively validated zero-cross period-amplitude module of PASS PLUS software. The EMD was measured as 0.3 to 2 Hz integrated amplitude per 20-second stage of rapid eye movement sleep. Eye-movement incidence was the number of half waves. Eye-movement amplitude was the sum of peak-trough excursions (curve length) in the average half wave. We also counted visually the number of 2-second epochs with eye movements for 1 baseline night in both groups. The EMD in the elderly subjects was substantially and significantly lower than in the young subjects. Visual scoring of EMD on 1 baseline night confirmed the statistically significant difference between age groups. Period-amplitude analysis revealed that a lower eye-movement incidence rather than reduced amplitude caused the lower EMD in the elderly. The EMD was significantly correlated within subjects across the nonconsecutive baseline nights in both groups; in both, subjects' EMD average across 2 nights provided a correlation greater than .90 with the 4-night mean. CONCLUSIONS: The incidence of eye movements during rapid eye movement sleep is substantially reduced in the elderly. We hypothesize that this reduction is due to degenerative (aging) rather than developmental brain changes. The correlation analysis indicates that EMD is a reasonably stable individual trait in both young and elderly adults. These results encourage normative studies of EMD over a wider age span and continued exploration of the relation of EMD to cognitive function in the elderly.     

Patterns of intellectual performance among recently abstinent alcohol abusers on WAIS-R and WMS-R sub-tests.

A group of recently abstinent alcohol abusers were examined using selected subtests of the WAIS-R and the WMS-R. The pattern of performance on the WAIS-R was similar to that well established for its predecessor. A clear nonmodality-specific memory deficit was evident on the WMS-R subtests. The theoretical and clinical implications of the results are briefly discussed.     

Effect of repeated administration of a neuropsychological battery in the elderly.

Our study explored the magnitude of practice effect in repeated administration of NP measures that tap different cognitive domains in normal elderly subjects (N = 122) between ages 57 and 85, who were evaluated over three annual testing probes. Results revealed that WAIS-R PIQ, serial recall of words, WMS visual memory, and memory for logical passages (immediate and delayed) are likely to improve on the retest due to practice effect in individuals below age 75, whereas test-retest changes in older people show a different pattern. Implications of age-specific changes on retest for differential diagnosis of dementia in clinical practice were considered.     

Findings before diagnoses of asthma among the elderly in a longitudinal study of a general population sample.

Forty elderly subjects who denied ever having asthma or emphysema on enrollment in a longitudinal epidemiologic study later reported consulting a doctor for asthma when they were older than 60 years of age. The average age at which the diagnosis was reported was 70.8 years, after a mean follow-up of 8.5 years. Findings on enrollment in the newly diagnosed subjects with asthma are compared with findings in the 1145 subjects who provided follow-up information when they were older than age 60 years but had never developed asthma. At the time of enrollment, most subjects later diagnosed as having asthma already had wheezing symptoms, suggesting at least a mild asthmatic state, and many subjects had impaired ventilatory function, a positive allergy skin test (especially in association with rhinitis), and blood eosinophilia. Thirty-five percent of the subjects recalled "respiratory trouble before age 16" despite denying prior asthma. The likelihood of a new asthma label was very closely related to the age-sex-standardized serum-IgE level before diagnosis. Newly diagnosed subjects with asthma demonstrated much greater rates of decline in FEV1 than control subjects or than subjects who already had known asthma on enrollment. We conclude that (1) symptoms suggesting asthma are usually present for many years before the diagnosis of the disease in elderly subjects, (2) the serum-IgE level is closely related to the likelihood of a subsequent asthma diagnosis, even in this age group, and (3) a rapid fall in lung function often occurs around the time of initial diagnosis.     

First-Last Names and the Grocery List Selective Reminding Test: two computerized measures of everyday verbal learning.

Data are presented on two computerized tests of everyday verbal learning: Paired associate learning of First-Last Names (FLN), and the Grocery List Selective Reminding Test (GLSRT). MANOVA and multiple regression analyses demonstrated that performance on FLN and GLSRT was most strongly related to age, with significant secondary associations found for gender, with females performing better than males. Additional factor analysis of FLN and GLSRT supported the construct validity of these measures by demonstrating significant associations of performance with traditional newopsychological measures of memory and related functions, including the Paired Associate Learning and Logical Memory subtests from the Wechsler Memory Scale, the Benton Visual Retention Test, and WAIS Digit Symbol.