The large number of primary Spanish speakers both in the United States and the world makes it imperative that appropriate neuropsychological assessment instruments be available to serve the needs of these populations. In this article we describe the norming process for Spanish speakers from the U.S.–Mexico border region on the Brief Visuospatial Memory Test-revised and the Hopkins Verbal Learning Test-revised. We computed the rates of impairment that would be obtained by applying the original published norms for these tests to raw scores from the normative sample, and found substantial overestimates compared to expected rates. As expected, these overestimates were most salient at the lowest levels of education, given the under-representation of poorly educated subjects in the original normative samples. Results suggest that demographically corrected norms derived from healthy Spanish-speaking adults with a broad range of education, are less likely to result in diagnostic errors. At minimum, demographic corrections for the tests in question should include the influence of literacy or education, in addition to the traditional adjustments for age. Because the age range of our sample was limited, the norms presented should not be applied to elderly populations.
Cross-cultural assessment; Spanish; Hispanic; Learning; Memory; Ethnic differences
This study assessed the clinical utility of contrast sensitivity (CS) relative to attention, executive function, and visuospatial abilities for predicting driving safety in participants with Parkinson's disease (PD). Twenty-five, non-demented PD patients completed measures of contrast sensitivity, visuospatial skills, executive functions, and attention. All PD participants also underwent a formal on-road driving evaluation. Of the 25 participants, 11 received a marginal or unsafe rating on the road test. Poorer driving performance was associated with worse performance on measures of CS, visuospatial constructions, set shifting, and attention. While impaired driving was associated with a range of cognitive and visual abilities, only a composite measure of executive functioning and visuospatial abilities, and not CS or attentional skills, predicted driving performance. These findings suggest that neuropsychological tests, which are multifactorial in nature and require visual perception and visual spatial judgments are the most useful screening measures for hazardous driving in PD patients.
Contrast sensitivity; Executive function; Visuospatial; Activities of daily living
The Driving Scenes test of the new Neuropsychological Assessment Battery (NAB; [Stern, R.A., & White, T. (2003a). Neuropsychological Assessment Battery. Lutz, FL: Psychological Assessment Resources, Inc.]) measures several aspects of visual attention thought to be important for driving ability. The current study examined the relationship between scores on the Driving Scenes test and on-road driving performance on a standardized driving test. Healthy participants performed significantly better on the Driving Scenes test than did very mildly demented participants. A correlation of 0.55 was found between the brief, office-based Driving Scenes test and the 108-point on-road driving score. Furthermore, the Driving Scenes test scores differed significantly across the driving instructor’s three global ratings (safe, marginal, and unsafe), and results of a discriminant function analysis indicated that the Driving Scenes test correctly classified 66% of participants into these groups. Thus, the new NAB Driving Scenes test appears to have good ecological validity for real-world driving ability in normal and very mildly demented older adults.
Driving; Aging; Dementia; Neuropsychology; Attention; Visual
There has been a relative absence of studies that have examined the neuropsychological profiles of potential lung transplant candidates. Neuropsychological data are presented for 134 patients with end-stage pulmonary disease who were being evaluated as potential candidates for lung transplantation. Neuropsychological test results indicated that a significantly greater proportion of the patients exhibited impaired performances on a number of Selective Reminding Test (SRT) tasks as compared to the expected population frequency distributions for these measures. The highest frequencies of impairment were observed on the SRT’s Immediate Free Recall (46.43%), Long-term Retrieval (41.67%), and Consistent Long-term Retrieval (51.19%) variables. On the Minnesota Multiphasic Personality Inventory-2 (MMPI-2)/Minnesota Multiphasic Personality Inventory-Adolescent (MMPI-A), patients’ mean clinical profile revealed elevations on Scales 1 (Hypochondriasis) and 3 (Conversion Hysteria). This profile indicated that they were experiencing an array of symptomatology ranging from somatic complaints to lethargy and fatigue, and that they may have been functioning at a reduced level of efficiency. Findings are discussed in light of patients’ end-stage pulmonary disease and factors possibly contributing to their neuropsychological test performances. Implications for clinical practice and future research are also provided.
Neuropsychology; Neurocognitive; Pulmonary disease; End-stage; Lung transplant
This study examined the sensitivity of diffusion tensor imaging (DTI) to microstructural white matter (WM) damage in mild and moderate pediatric traumatic brain injury (TBI). Fourteen children with TBI and 14 controls ages 10–18 had DTI scans and neurocognitive evaluations at 6–12 months post-injury. Groups did not differ in intelligence, but children with TBI showed slower processing speed, working memory and executive deficits, and greater behavioral dysregulation. The TBI group had lower fractional anisotropy (FA) in three WM regions: inferior frontal, superior frontal, and supracallosal. There were no group differences in corpus callosum. FA in the frontal and supracallosal regions was correlated with executive functioning. Supracallosal FA was also correlated with motor speed. Behavior ratings showed correlations with supracallosal FA. Parent-reported executive deficits were inversely correlated with FA. Results suggest that DTI measures are sensitive to long-term WM changes and associated with cognitive functioning following pediatric TBI.
Traumatic brain injury (TBI); Diffusion tensor imaging (DTI); White matter; Pediatric
Dementia screening batteries often fall short on measures of executive functioning. The Weigl Color Form Sorting Test (WCFST) is a candidate for inclusion in such batteries, but can be insensitive to mild disturbance. The WCFST consists of 12 colored geometric shapes and requires the patient to sort the pieces by color or form, and then shift to the other sorting principle unassisted. We created a modified version of the WCFST (the Weigl-R) with increased conceptual complexity by adding two stimulus dimensions (texture and central shapes). The range of scores was also increased by adding the extent of examiner assistance required to achieve a correct sort, ability to verbalize conceptual strategy, and number of perseverations. We administered the Weigl-R to a group of 30 patients with mixed dementias, 34 adults with cognitive impairment without dementia, and 21 healthy controls. The new measure discriminated well between healthy controls and older adults with either cognitive impairment without dementia, or dementia. The Weigl-R may be a useful adjunct to brief dementia batteries but requires further validation.
Dementia; Executive functioning; Neuropsychology; Conceptual reasoning
The purpose of this study was to examine the impact of age, sex, and education on category and letter verbal fluency task performance. A secondary goal was to examine whether resting EEG theta power in bilateral frontal and temporal lobes impacts age-associated decline in verbal fluency task performance. A large sample (N=471) of healthy, normal participants, age 21–82, was assessed for letter fluency (i.e., FAS), and for category fluency (i.e., Animal Naming), and with a 32-channel EEG system for ‘eyes-open’ resting theta power. The effects of age, sex, and education were examined using analyses of variance. Correlation analyses were used to test the impact of theta power on age and fluency performance by controlling for the effects of theta when examining the relationship between the other two variables. The results indicated that performance on both fluency tests declined linearly with age, but that the rate of decline was greater for category fluency. These age changes were not associated with education level, and there were no sex differences. While theta power was negatively associated with age and positively associated with Animal Naming performance, it did not moderate the relationship between the two. The differential age-associated decline between category and letter fluency suggests separate neurobiological substrates underlying the two domains of performance, which is not related to theta activity.
Normal aging; Category fluency; Letter fluency; EEG; Theta
The Clock Drawing Test (CDT) is a common neuropsychological measure sensitive to cognitive changes and functional skills (e.g., driving test performance) among older adults. However, normative data have not been adequately developed. We report the distribution of CDT scores using three common scoring systems (Mendez, Ala, and Underwood, 1992; Freund, Gravenstein, Ferris, Burke, & Shaheen, 2005; and Cahn, Salmon, Monsch, Butters, Wiederholt, & Corey-Bloom, 1996), among 207 cognitively normal elderly. The systems were well correlated, took little time to use, and had high inter-rater reliability. We found statistically significant differences in CDT scores based on age and WRAT-3 Reading score, a marker of education quality. We present means, standard deviations, and t- and z-scores based on these subgroups. We found that “normal” CDT performance includes a wider distribution of scores than previously reported. Our results may serve as useful comparisons for clinicians wishing to know whether their patients perform in the general range of cognitively normal elderly.
Clock Drawing Test; clock drawing; normal aging; normative data; scoring systems; neuropsychological tests; elderly; Alzheimer’s disease; mild cognitive impairment; dementia; cognitive decline; cognitive screening
To clinically characterize performance on the Hooper Visual Organization Test (HVOT) among participants with mild cognitive impairment (MCI) and to identify naming and executive functioning correlates associated with HVOT performance among MCI participants and normal controls (NC).
The HVOT is a common neuropsychological instrument that measures visuospatial skills and agnosia. It has, however, been criticized for its multifactorial nature, as several studies have reported executive or language correlates of HVOT performance. To our knowledge, simultaneous comparison of executive functioning and language demands of the HVOT has never been performed among an older cohort.
The HVOT, two tests of executive functioning [Trail Making Test, Part B (TMT-B), Controlled Oral Word Association (COWA)] and two tests of naming [abbreviated Boston Naming Test (BNT), Animal Naming] were administered to 222 NC, 166 MCI, and 68 Alzheimer’s disease (AD) individuals.
HVOT scores were significantly different between all three groups in the expected direction (AD < MCI < NC). Linear regression among NC participants revealed that COWA, age, and BNT were significantly associated with HVOT scores, accounting for 12%, 6%, and 4% of HVOT variance, respectively. Among MCI participants, the BNT accounted for 43% of HVOT variance. Neither TMT-B nor Animal Naming was a significant predictor for either group.
Among NC participants, rapid word generation (i.e., COWA), a measure of executive functioning, is the most salient predictor of HVOT performance. In contrast, lexical retrieval (i.e., BNT) is the most salient language or executive functioning predictor of HVOT performance among MCI participants. These findings extend previous claims that the HVOT is multifactorial by suggesting that reduced HVOT performance in MCI patients may be related to mild lexical retrieval impairments.
Object recognition; Mild cognitive impairment; Hooper Visual Organization Test
Executive functioning has been repeatedly linked to the integrity of instrumental activities of daily living (IADL). The present study examined the association of multiple executive functioning elements (i.e., working memory, generation, inhibition, planning, and sequencing) to IADLs among an older adult cohort at risk for future cognitive and functional decline.
Seventy-two participants with prevalent but stable cardiovascular disease completed a neuropsychological protocol assessing multiple elements of executive functioning, including COWA, PASAT, DKEFS Color-Word Interference Test, DKEFS Trail-Making Test, DKEFS Tower Test, and Ruff Figural Fluency Test. Reliable informants completed a measure of IADLs.
Stepwise logistic regression selected a model involving a single significant predictor, a measure of inhibition (i.e., DKEFS Color-Word Interference Test), which had a significant regression coefficient. Subsequent correlation analyses confirmed an association between the inhibition measure and multiple IADL items. Inter-item comparisons among the IADLs revealed significant differences, such that telephone use and laundry were significantly more intact than most other IADLs while shopping and housekeeping were most compromised.
Our data suggest that inhibition, also known as susceptibility to interference, is most strongly related to IADL impairment among patients at risk for future cognitive and functional decline.
Cardiovascular disease; Neuropsychology; Cognition; Executive functioning; Instrumental activities of daily living (IADLs); Delis-Kaplan Executive Function System (D-KEFS); Inhibition; Geriatric
Verbal fluency tests are employed regularly during neuropsychological assessments of older adults, and deficits are a common finding in patients with Alzheimer’s disease (AD). Little extant research, however, has investigated verbal fluency ability and subtypes in preclinical stages of neurodegenerative disease. We examined verbal fluency performance in 107 older adults with amnestic mild cognitive impairment (MCI, n = 37), cognitive complaints (CC, n = 37) despite intact neuropsychological functioning, and demographically-matched healthy controls (HC, n = 33). Participants completed fluency tasks with letter, semantic category, and semantic switching constraints. Both phonemic and semantic fluency were statistically (but not clinically) reduced in amnestic MCI relative to cognitively intact older adults, indicating subtle changes in both the quality of the semantic store and retrieval slowing. Investigation of the underlying constructs of verbal fluency yielded two factors: Switching (including switching and shifting tasks) and Production (including letter, category, and action naming tasks), and both factors discriminated MCI from HC albeit to different degrees. Correlational findings further suggested that all fluency tasks involved executive control to some degree, while those with an added executive component (i.e., switching and shifting) were less dependent on semantic knowledge. Overall, our findings highlight the importance of including multiple verbal fluency tests in assessment batteries targeting preclinical dementia populations and suggest that individual fluency tasks may tap specific cognitive processes.
Mild cognitive Impairment; Verbal Fluency; Assessment; Cognition
The current study provided longitudinal robust norms for individuals age 70 years and older for several neuropsychological tests. We compared baseline neuropsychological test performance in three groups free of dementia at baseline: a robust normative sample free of dementia for at least two post-follow-up assessments, an incident dementia sample which developed new onset dementia during the follow-up and a Lost to Follow-up (LTF) sample. ANCOVAs showed that the robust sample performed better on all neuropsychological tests compared to the incident dementia and LTF samples. These findings support the argument that individuals in transition to developing dementia may reduce the mean, increase the variability and therefore underestimate cognitive performance in normal aging. We suggest that longitudinal robust norms may help mitigate the limitations inherent in cross-sectional normative samples.
Aging; Norms; Dementia; Attrition
Although initially developed as a brief dementia battery, the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) has not yet demonstrated its sensitivity, specificity, and positive and negative predictive powers in detecting cognitive impairment in patients with Alzheimer’s disease (AD). Therefore, the current study examined the clinical utility of the RBANS by comparing two age-, education-, and gender-matched groups: patients with AD (n=69) and comparators (n=69). Significant differences (p<0.001) were observed on the RBANS Total score, all five Indexes, and all twelve subtests, with patients performing worse than the comparison participants. An optimal balance between sensitivity and specificity on RBANS scores was obtained when cutoffs of one and one and a half standard deviations below the mean of the comparison sample were implemented. Areas under the Receiver Operating Characteristic curves for all RBANS Indexes were impressive though Immediate and Delayed Memory Indexes were excellent (0.96 and 0.98, respectively). Results suggest that RBANS scores yield excellent estimates of diagnostic accuracy and that the RBANS is a useful screening tool in detection of cognitive deficits associated with AD.
Alzheimer’s disease; dementia; diagnostic accuracy; Repeatable Battery for the Assessment of Neuropsychological Status
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.
Subcortical hyperintensities; Cognition; Elderly; MRI
Few studies have examined the neuropsychological sequelae associated with end-stage pulmonary disease. Neuropsychological data are presented for 47 patients with end-stage chronic obstructive pulmonary disease (COPD) who were being evaluated as potential candidates for lung transplantation. Although patients exhibited a diversity of neurocognitive deficits, their highest frequencies of impairment were found on the Selective Reminding Test (SRT). Specifically, over 50% of the patients completing the SRT exhibited impaired immediate free recall and consistent long-term retrieval deficits, while more than 44% of these individuals displayed deficient long-term retrieval. Deficient SRT long-term storage strategies, cued recall, and delayed recall were exhibited by between 26% and 35% of these patients, while more than 32% of this sample displayed elevated numbers of intrusion errors. Over 31% of the patients completing the Wisconsin Card Sorting Test (WCST) failed to achieve the expected number of categories on this measure, while more than 23% of these individuals demonstrated elevated numbers of perseverative errors and total errors. Clinically notable frequencies of impairment (greater than 20% of the sample) were also found on the Trail Making Test (TMT): Part B and the Wechsler Memory Scale-R (WMS-R) Visual Reproduction II subtest. Minnesota Multiphasic Personality Inventory-2 (MMPI-2) personality assessments indicated that patients were experiencing a diversity of somatic complaints and that they may have been functioning at a reduced level of efficiency. These findings are discussed in light of patients’ end-stage COPD and factors possibly contributing to their neuropsychological test performances. Implications for clinical practice and future research are also included.
Neuropsychological dysfunction; Chronic obstructive pulmonary disease; Lung transplantation
Trail Making Test; errors; geriatrics; MCI; AD; executive functioning
To examine patterns of executive dysfunction associated with ADHD, 123 children (54 ADHD, 69 controls) ages 8–16 years were administered selected subtests from the Delis-Kaplan Executive Function System (D-KEFS). Children with ADHD performed significantly worse than controls on measures of both basic (less executive demand) skills and those with more executive demand from the Color-Word Interference and Tower subtests; however, no group differences were noted on any of the D-KEFS contrast scores. Most subtype comparisons yielded no differences; however, children with the Combined subtype outperformed children with the Inattentive subtype on measures of both basic and executive skills from the Trail Making Test. Children with ADHD demonstrate executive dysfunction that is identified by both D-KEFS summary, but not contrast scores. In this carefully screened sample of children with ADHD, few significant differences were found between groups suggesting limited sensitivity or specificity of the D-KEFS for classifying children with ADHD.
ADHD; Subtype; Executive Function; Classification; Children; Pediatrics
Optimal adherence to antiretroviral medications is critical to the effective long-term management of HIV infection. Although prospective memory (ProM; i.e., “remembering to remember”) has long been theorized to play an important role in medication adherence, no prior studies have evaluated whether HIV-associated ProM impairment possesses unique predictive value in this regard. Results from this study demonstrate a robust association between ProM impairment and self-reported medication management in 87 HIV-infected persons currently prescribed antiretroviral medications. Specifically, more frequent ProM complaints and performance deficits on both laboratory and semi-naturalistic ProM tasks were all independently related to poorer self-reported medication management. A series of hierarchical regression analyses revealed that HIV-associated ProM impairment accounted for a significant amount of variance in self-reported medication management beyond that which was explained by other factors known to predict nonadherence, including mood disorders, psychosocial variables, environmental structure, and deficits on a traditional battery of neuropsychological tests. Overall, these findings support the hypothesis that ProM captures a unique and largely untapped aspect of cognition that is germane to optimal medication adherence. The potential benefits of individualized remediation strategies that are informed by conceptual models of ProM and specifically target medication adherence warrant further exploration.
Human immunodeficiency virus; Neuropsychological assessment; Episodic memory; Treatment compliance
This study tested the convergence of behavioral inhibition measures across emotional and non-emotional versions of the same go/no-go task in 85 college students. The two tasks differed only in the stimuli used for trial cues (i.e., circles versus facial expressions). Moderate correlations (r = .51 to r = .56) between commission errors across the emotional and non-emotional tasks support the construct validity of behavioral inhibition. Further, parametric manipulation of preceding context had comparable effects on performance on the two tasks. Responses were slower and more variable, commission errors were more numerous, and perceptual sensitivity was lower on the emotional than the non-emotional task. A bias for happy faces on the emotional task resulted in faster responses and more commission errors for happy than sad faces despite marginally greater sensitivity for the latter. These results suggest that the basic neuropsychological constructs of the original go/no-go task were preserved in the emotional adaptation.
Behavioral inhibition; emotional bias; construct validity; go/no-go task
The Philadelphia Face Perception Battery (PFPB) tests four aspects of face perception: discrimination of facial similarity, attractiveness, gender, and age. Calibration with 116 neurologically intact subjects yielded average performance of ~90%. Across subjects, there was a low correlation (<0.22) in performance between the tests (with the exception of the attractiveness and age discrimination tests) suggesting that the tests measure independent aspects of face perception. There were modest effects of subject demographic factors upon performance, and test-retest reliability scores (between 0.37 and 0.75) were comparable to other neuropsychological batteries. Modification of the stimuli to obscure internal facial features lowered performance on the age, gender, and attractiveness discrimination tests between 2 and 4 standard deviations. The clinical sensitivity of the battery was demonstrated by testing a patient with acquired prosopagnosia. She showed performance impairments of between 2 and 4 standard deviations on all sub-tests. The PFPB is freely available for non-commercial use.
Face perception; prosopagnosia; facial beauty; neuropsychological testing
Patients with attention-deficit/hyperactivity disorder (ADHD) can be slow at switching between stimuli, or between sets of stimuli to control behaviour appropriate to changing situations. We examined clinical and experimental parameters that may influence the speed of such processes measured in the trail-making (TMT) and switch-tasks in cases with ADHD combined-type, their non-affected siblings and unrelated healthy controls. The latency for completion of the trail-making task controlling for psychomotor processing (TMT B–A) was longer for ADHD cases, and correlated with Conners’ ratings of symptom-severity across all subjects. The effect decreased with age. Switch-task responses to questions of “Which number?” and “How many?” between sets of 1/111 or 3/333 elicited differential increases in latency with condition that affected all groups. But there was evidence for increased symptom-related intra-individual variability among the ADHD cases, and across all subjects. Young siblings showed familiality for some measures of TMT and switch-task performance but these were modest. The potential influence of moderator variables on the efficiency of processing stimulus change rather than the speed of processing are discussed.
ADHD; attention; heritability; risk; siblings; set; switch; trail-making
Failures of episodic retrospective memory (RetM) are among the most frequently reported cognitive complaints endorsed by individuals living with HIV infection. The present study sought to examine the nature, frequency, and determinants of self-reported complaints of prospective memory (ProM) in HIV, which is a singly dissociable and ecologically relevant aspect of episodic memory involving the execution of future intentions. Seventy-five HIV seropositive individuals and 60 seronegative volunteers were administered the Prospective and Retrospective Memory Questionnaire (PMRQ) as part of extensive neuropsychological, psychiatric, and medical research assessments. The HIV sample endorsed more frequent ProM complaints in daily life than the seronegative group, particularly on items requiring self-initiated cue detection and retrieval. Within both study groups, ProM complaints were significantly more frequent than RetM complaints. Although the HIV sample was impaired relative to the seronegative group on an objective, performance-based ProM test, self-reported ProM complaints did not correspond to actual ProM abilities. However, greater frequency of self-reported ProM complaints was moderately associated with increased fatigue, as well as with symptoms of anxiety and depression. Consistent with prior research on RetM in HIV, results indicate that affective distress contributes to a metamemory deficit for HIV-associated ProM impairment, which highlights the potential importance of assessing both self-reported and performance-based ProM in clinical and research neuroAIDS evaluations.
Human immunodeficiency virus; Neuropsychological assessment; Self-report; Fatigue; Episodic memory; Metacognition
Practice effects, defined as improvements in cognitive test performance due to repeated exposure to the test materials, have traditionally been viewed as sources of error. However, they might provide useful information for predicting cognitive outcome. The current study used three separate patient samples (older adults with mild cognitive impairments, individuals who were HIV +, individuals with Huntington’s disease) to examine the relationship between practice effects and cognitive functioning at a later point. Across all three samples, practice effects accounted for as much as 31 to 83% of the variance in the follow-up cognitive scores, after controlling for baseline cognitive functioning. If these findings can be replicated in other patients with neurodegenerative disorders, clinicians and researchers may be able to develop predictive models to identify the individuals who are most likely to demonstrate continued cognitive decline across time. The ability to utilize practice effects data would add a simple, convenient, and non-invasive marker for monitoring an individual patient’s cognitive status. Additionally, this prognostic index could be used to offer interventions to patients who are in the earliest stages of progressive neurodegenerative disorders.
practice effects; cognitive outcome; Mild Cognitive Impairment; HIV; Huntington’s disease
Normative neuropsychological data for U.S. racial/ethnic minorities is limited. Extant norms are based on small, regional groups that may not be nationally representative. The objectives of this study were to 1) provide norms for a modified Symbol Digit Modalities Test (M-SDMT) based on a nationally representative sample of African Americans, Caribbean Blacks and non-Latino Whites (NLW) living in areas with large populations of Blacks, and 2) determine significant correlates of M-SDMT performance. The M-SDMT was administered to a subset of respondents from the National Survey of American Life in standard, face-to-face interviews. M-SDMT performance was influenced by race/ethnicity, age, education, and gender. African Americans and NLW groups had similar M-SDMT performances, which differed from Caribbean Blacks. The Black ethnic differences in M-SDMT were not explained by the sociodemographic factors considered in this study. Unlike previous work, this study supports the consideration of Black ethnicity when evaluating Black neuropsychological test performance.
African Americans; Caribbean Blacks; Blacks; Neuropsychological Tests