Impairment in semantic processing occurs early in Alzheimer's disease (AD) and differential impact on subtypes of semantic relations have been reported, yet there is little data on the neuroanatomic basis of these deficits. Patients with mild AD and healthy controls underwent 3 functional MRI auditory stimulation tasks requiring semantic or phonological decisions (match–mismatch) about word pairs (category–exemplar, category–function, pseudoword). Patients showed a significant performance deficit only on the exemplar task. On voxel-based fMRI activation analyses, controls showed a clear activation focus in the left superior temporal gyrus for the phonological task; patients showed additional foci in the left dorsolateral prefrontal and bilateral cingulate areas. On the semantic tasks, predominant activation foci were seen in the inferior and middle frontal gyrus (left greater than right) in both groups but patients showed additional activation suggesting compensatory recruitment of locally expanded foci and remote regions, for example, right frontal activation during the exemplar task. Covariance analyses indicated that exemplar task performance was strongly related to signal increase in bilateral medial prefrontal cortex. The authors conclude that fMRI can reveal similarities and differences in functional neuroanatomical processing of semantic and phonological information in mild AD compared to healthy elderly, and can help to bridge cognitive and neural investigations of the integrity of semantic networks in AD. (JINS, 1999, 5, 377–392.)

Objective Neurocognitive impairments in schizophrenia are well replicated and widely regarded as candidate endophenotypes that may facilitate understanding of schizophrenia genetics and pathophysiology. The Project Among African-Americans to Explore Risks for Schizophrenia (PAARTNERS) aims to identify genes underlying liability to schizophrenia. The unprecedented size of its study group (N=1,872), made possible through use of a computerized neurocognitive battery, can help further investigation of the genetics of neurocognition. The current analysis evaluated two characteristics not fully addressed in prior research: 1) heritability of neurocognition in African American families and 2) relationship between neurocognition and psychopathology in families of African American probands with schizophrenia or schizoaffective disorder. Method Across eight data collection sites, patients with schizophrenia or schizoaffective disorder (N=610), their biological relatives (N=928), and community comparison subjects (N=334) completed a standardized diagnostic evaluation and the computerized neurocognitive battery. Performance accuracy and response time (speed) were measured separately for 10 neurocognitive domains. Results The patients with schizophrenia or schizoaffective disorder exhibited less accuracy and speed in most neurocognitive domains than their relatives both with and without other psychiatric disorders, who in turn were more impaired than comparison subjects in most domains. Estimated trait heritability after inclusion of the mean effect of diagnostic status, age, and sex revealed significant heritabilities for most neurocognitive domains, with the highest for accuracy of abstraction/ flexibility, verbal memory, face memory, spatial processing, and emotion processing and for speed of attention. Conclusions Neurocognitive functions in African American families are heritable and associated with schizophrenia. They show potential for gene-mapping studies.

Working memory is the cognitive ability to hold a discrete amount of information in mind in an accessible state for utilization in mental tasks. This cognitive ability is impaired in many clinical populations typically assessed by clinical neuropsychologists. Recently, there have been a number of theoretical shifts in the way that working memory is conceptualized and assessed in the experimental literature. This study sought to determine to what extent the WAIS-III working memory index (WMI) measures the construct studied in the cognitive working memory literature, whether an improved WMI could be derived from the subtests that comprise the WAIS-III, and what percent of variance in individual WAIS-III subtests is explained by working memory. It was hypothesized that subtests beyond those currently used to form the WAIS-III WMI would be able to account for a greater percentage of variance in a working memory criterion construct than the current WMI. Multiple regression analyses (n = 180) revealed that the best predictor model of subtests for assessing working memory was composed of the Digit Span, Letter-Number Sequencing, Matrix Reasoning, and Vocabulary. The Arithmetic subtest was not a significant contributor to the model. These results are discussed in the context of how they relate to Engle's (2006, 2007) new conceptualization of working memory mechanisms. KeywordsNeuropsychological Assessment; Working Memory; WAIS-III; Dual-Component Model Working memory refers to the cognitive system that stores information in an accessible state for utilization in complex mental tasks. This system also allows for updating and manipulation of relevant information. It is composed of both passive storage and dynamic control processes in order to hold information in an active form (Baddeley, 2001). Working memory is impaired in a wide variety of neuropsychiatric conditions, including dementia

This study aimed to provide normative references for Mexican Americans on neuropsychological measures of cognitive functioning. Data were analyzed from a total of 797 Mexican-Americans recruited across three Texas-based studies with approximately one-half of the participants tested in Spanish. Normative tables include: MMSE, AMNART, WMS-III (Logical Memory I, II; Visual Reproduction I, II; Digit Span), CERAD, RAVLT, Exit25, CLOX 1 & 2, Trail Making Test- A&B, BNT, COWA, and Animal Naming. The norms were stratified by education then age. Normative references were generated for Texas-based Mexican Americans and data may be limited to the population sampled.

Demographic variables have long been known to exert effects on psychological testing. Variables such as age, education, and gender have been thoroughly researched, and their effects are well documented. Other demographic variables such as race, ethnicity, socioeconomic status, native language, and acculturation are less well researched within the field of neuropsychology. Research that has been produced to date has demonstrated that each of these variables does indeed wield some effect on neuropsychological test performance. Therefore, it is important that these variables be reported in the literature so that neuropsychologists are able to generalize research findings to their everyday practice with patients from diverse backgrounds. With this in mind, the current study was undertaken in order to determine the frequency with which a range of demographic variables are being reported in current neuropsychological research journals. Publications from 1995 to 2000 in five of the most frequently utilized neuropsychology journals were reviewed. Results showed that while age, education, and gender are frequently reported, information on race, ethnicity, native language, and acculturation are rarely, if ever, reported. These results show that even though great strides have been taken in the burgeoning field of cross-cultural neuropsychology, current trends need to be changed in order for progress to continue.