Standardization data for the Children's Category Test (CCT) and California Verbal Learning Test–Children's Version (CVLT–C) were used to evaluate covariances and statistically significant discrepancies between the T scores of those instruments, as well as the base rate of specific discrepancies. The results indicate that the CCT and CVLT–C share only a limited amount of common variance and that statistically significant discrepancies between the respective T scores are actually quite common. It is suggested that evaluation of the potential clinical significance of a discrepancy between the obtained results of these two instruments in individual cases should include consideration of the presented base rates. (JINS, 1998, 4, 242–246.)

A new test of strategy application was designed to be relatively free of the constraints that limit the standard neuropsychological assessment of supervisory abilities. The validity of the test was assessed in 3 samples of participants with varying degrees of supervisory deficits and frontal systems dysfunction: focal frontal lesions, traumatic brain injury (TBI), and normal aging. Inefficient strategy application varied systematically across the 3 groups and was not due to extraneous factors such as forgetting the test instructions. Previous case studies have emphasized strategy application deficits in the face of normal neuropsychological test performance. In this study, it was shown that strategically impaired participants from a consecutive series can include those both with and without deficient neuropsychological test performance. When neuropsychological impairment was present, it was greatest on executive functioning tasks. Among participants with nonstrategic performance, there was evidence for a dissociation of knowledge from action. This finding was not specific to focal frontal lesions. A number of supervisory processes contributing to strategy application were identified. Exploratory analyses indicated differential effects of lesion location on these processes, especially inferior medial frontal and right hemisphere lesions. Overall, the results supported the use of unstructured tasks in the assessment of supervisory abilities. (JINS, 1998, 4, 247–264.)

Seventy-four patients with focal brain lesions were compared to a neurologically normal control group on tasks of letter-based and category-based list generation. When patients were divided only by right frontal, left frontal, or nonfrontal lesion sites, the pattern of fluency impairments confirmed prior claims. When more precise lesion sites within the frontal lobes were compared between groups classified based on their fluency performance, much more specific brain–behavior relations were uncovered. Damage to the right dorsolateral cortical or connecting striatal regions, the right posterior area, or the medial inferior frontal lobe of either hemisphere did not significantly affect letter-based fluency performance. Superior medial frontal damage, right or left, resulted in moderate impairment. Patients with left dorsolateral and/or striatal lesions were most impaired. Left parietal damage led to performance relatively equivalent to the superior medial and left dorsolateral groups. The same lesion sites produced impairments in category based fluency, but so did lesions of right dorsolateral and inferior medial regions. Task analysis and correlations with other measures revealed that different cognitive processes related to different brain regions underlie performance on verbal fluency tests. (JINS, 1998, 4, 265–278.)

No previous comparison of test performance in probable Alzheimer's disease (pAD) and Parkinson's disease (PD) dementia has provided information about potential differences in the dementing process. This study compared the evolution of cognitive changes associated with these dementias. Generalized estimating equations (GEE) applied to regression analyses with repeated measures were used to evaluate cognitive changes over 1 to 3 years prior to the point when dementia was diagnosed in 40 matched pairs of patients with incident pAD and PD dementia. Both groups' performance declined on the Short Blessed, Selective Reminding Test (SRT; total recall, long-term retrieval, and delayed recall), Boston Naming Test, Category Fluency, and Similarities. The decline on naming and SRT delayed recall was more rapid in the PD dementia group, suggesting that these performance deficits emerge earlier in the development of pAD. The PD dementia group performed worse on Category Fluency throughout the follow-up period, suggesting either that dementia is overlaid on this preexisting performance deficit or that this type of executive deficit is an early manifestation of dementia in PD. The pAD group performed more poorly throughout the follow-up period on SRT delayed recognition, consistent with a pAD-specific encoding deficit. We conclude that while pAD and PD dementia are similar in many respects, differences in their evolution support previous observation of unique features in the 2 dementias and suggest different underlying pathologies. (JINS, 1998, 4, 279–284.)

It is controversial whether age of disease onset is related to cognitive decline in Parkinson's disease (PD). We administered 7 cognitive measures assessing visuospatial skills, memory, and executive functions to 222 patients with idiopathic PD and 108 normal control participants. Regression analyses demonstrated that older age of disease onset consistently predicted cognitive decline above and beyond normative aging and duration of illness. These findings suggest that older age of disease onset is a critical determinant of cognitive deterioration in PD. (JINS, 1998, 4, 285–290.)

Two studies were conducted to examine the relationship of acculturation to neuropsychological test performance among (1) medically healthy, neurologically normal African Americans (N = 170); and (2) HIV positive (HIV+) subgroups of African Americans and Whites (Ns = 20) matched on age, education, sex, and HIV disease stage. Acculturation was measured through self report for all participants, and linguistic behavior (Black English use) was assessed in a subset of medically healthy individuals (N = 25). After controlling for the effects of age, education, and sex, medically healthy African Americans who reported less acculturation obtained lower scores on the WAIS–R Information subtest and the Boston Naming Test than did more acculturated individuals. Black English use was associated with poor performance on Trails B and the WAIS–R Information subtest. HIV+ African Americans scored significantly lower than their HIV+ White counterparts on the Category Test, Trails B, WAIS–R Block Design and Vocabulary subtests, and the learning components of the Story and Figure Memory Tests. However, after accounting for acculturation, ethnic group differences on all measures but Story Learning became nonsignificant. These results suggest that there are cultural differences within ethnic groups that relate to neuropsychological test performance, and that accounting for acculturation may improve the diagnostic accuracy of certain neuropsychological tests. (JINS, 1998, 4, 291–302.)