This study examined the distinction between identification and production processes in repetition priming for 16 patients with Alzheimer's disease (AD) and 16 healthy old control participants (NC). Words were read in three study phases. In three test phases, participants (1) reread studied words, along with unstudied words, in a word-naming task (identification priming); (2) completed 3-letter stems of studied and unstudied words into words in a word-stem completion task (production priming); and (3) answered yes or no to having read studied and unstudied words in a recognition task (explicit memory). Explicit memory and word-stem completion priming were impaired in the AD group compared to the NC group. After correcting for baseline slowing, word-naming priming magnitude did not differ between the groups. The results suggest that the distinction between production and identification processes has promise for explaining the pattern of preservation and failure of repetition priming in AD. (JINS, 2001, 7, 785–794.)

Severe diffuse traumatic brain injury (TBI) may impair the performance of daily-life complex activities. The aim of the present study was to assess whether these difficulties are related to a representational impairment of action knowledge. Two tasks requiring the manipulation of scripts were used. The first (script reconstitution) required subjects to sort cards describing actions belonging to 4 different scripts, presented in a random order. The second (script generation) required subjects to generate actions belonging to a given script. The results showed that TBI patients had preserved access to goal representation and action knowledge. However, they demonstrated (1) significant impairments when they had to deal with simultaneous competing sources of information and (2) a lack of inhibitory control on routine overlearned skills. Patients' performance was significantly correlated with behavioral modifications in everyday life. These data suggest that action impairment in severe TBI patients cannot be attributed to an impairment of action knowledge per se. As previously suggested by Schwartz et al., a restriction of limited-capacity processing resources may account for the observed deficits. (JINS, 2001, 7, 795–804.)

Lesch-Nyhan disease (LND) is a rare, X-linked genetic disorder that involves the nearly complete absence of an enzyme (hypoxanthine-guanine phosphoribosyltransferase, or HPRT) that is essential for purine salvage. In addition to hyperuricemia, all patients with classic LND suffer from movement disorder and compulsive self-injury, and most have mental retardation. Patients with partial HPRT deficiency (variants) always have hyperuricemia and often have neurologic abnormalities, but do not self-injure and usually are described as having normal intelligence. Here we compare 15 patients with LND to 9 variants and 13 normal adolescents and adults. Testing revealed unambiguous and qualitatively similar cognitive deficits in both patient groups. The variants produced scores that were intermediate between those of patients with LND and normal participants on nearly every cognitive measure. We discuss these findings in terms of what is known about the neuropathology of LND. (JINS, 2001, 7, 805–812.)

Subtraction of serial scores, Least Squares Estimators, and Best Linear Unbiased Predictors (BLUPs) were compared for estimating rates of cognitive change for Mini-Mental State Exam (MMSE) and Dementia Rating Scale (DRS) scores for 299 probable Alzheimer's disease patients. The BLUPs provided cleaner group estimates of subjects' intercepts and slopes and are preferred. Regression analysis of the BLUP estimates of rate of change indicated that steeper declines were associated with higher levels of education and older age at onset. These effects were much smaller than those due to estimated initial cognitive test score. Differences in longitudinal metric characteristics of the MMSE and DRS were found, with the DRS yielding more precise change estimates. We discuss modeling these longitudinal data, and discuss use of the estimates of rate of change and intercept as data in their own right. (JINS, 2001, 7, 813–824.)

We describe the standardization of three new tests of knowledge of quantity facts, number operations and multiplication facts. We also report a validation study in which a group of 50 patients with cortical degenerative disorders were tested on these three new tests of number processing. Our results show that the quantity facts and number operations tests are sensitive measures of number processing abilities. Performance on the three new tests and the Graded Difficulty Arithmetic (GDA) test were found to be significantly impaired in the Alzheimer's Disease (AD) group. The frontotemporal dementia (FTD) group was subdivided into those with a semantic dementia (SD) and those with prominent frontal features (Non-SD). The semantic dementia subgroup was more impaired than both the AD patient group and the nonsemantic FTD subgroup on the quantity facts test. A more fine grained analysis reveals several interesting patterns of performance, including a dissociation between impaired performance on the quantity facts and number operations tests and preserved performance on the GDA. The findings attest the value of comparing performance on the GDA and our new tests in delineating the nature of an individual's number processing deficits. Implications for the relation between simple arithmetic fact knowledge and higher level number processing are discussed. (JINS, 2001, 7, 825–834.)

Gulf War unexplained illnesses (GWUI) are a heterogeneous collection of symptoms of unknown origin known to be more common among veterans of the Gulf War than among nonveterans. In the present study we focused on one of these unexplained illnesses. We tested the hypothesis that in a sample of Persian Gulf War veterans chronic fatigue syndrome (CFS) was associated with cognitive deficits on computerized cognitive testing after controlling for the effects of premorbid cognitive differences. We obtained Armed Forces Qualification Test (AFQT) data acquired around the date of induction into the military on 94 veterans of the Gulf War, 32 with CFS and 62 healthy controls. Controls performed better than participants diagnosed with CFS on the AFQT. Cognitive deficits were associated with CFS on 3 of 8 variables after the effect of premorbid AFQT scores was removed with ANCOVA. (JINS, 2001, 7, 835–839.)

To provide referential normative data on simple tasks dealing with number processing and calculation which could be used in clinical investigations, 551 normal volunteers aged between 18 and 69 years from France and Belgium (n = 180), Italy (n = 212) and Germany (n = 159), performed the 31 tasks which constitute the EC301 calculation and number processing battery. Differences between countries were significant for 16 tasks and a Gender × Education interaction was observed for some tasks, with men performing better than women among subjects with low education only. To present an overview of preserved and impaired calculation and number processing abilities in left-brain damaged (LBD) aphasic patients and right-brain damaged (RBD) nonaphasic patients, the 31 subtests of the EC301 battery were proposed to 80 patients with cerebrovascular accident, 56 left and 24 right, for most cases in the territory of the middle cerebral artery. LBD aphasic patients showed low performance on oral and alphabetical spoken verbal and written verbal counting, transcoding when a written code was involved, and mental or written calculation; but relatively good performance at finding the number of elements in small sets, comparing numbers written in the Arabic digital code and placing correctly numbers on an analogue number line. The lowest performances of RBD patients were observed for estimation tasks and for placing a number on a scale. Results and their implications for further research are discussed according to the present information processing and anatomofunctional models of calculation and number processing. (JINS, 2001, 7, 840–859.)

While some of the modifications made to produce the WAIS–III and WMS–III (Wechsler, 1997a, 1997b) make sense from a neuropsychological standpoint, there are many questions still unanswered about the validity and reliability of these tests and their ultimate utility to neuropsychologists. The new tests have been criticized for having long administration times, which is problematic given pressures to decrease rather than increase the length and cost of neuropsychological evaluations (Ryan et al., 1998). Clinical neuropsychologists want to know if these tests can help them evaluate their patients more accurately with greater sensitivity and specificity than the alternatives, and experimental neuropsychologists want to know if they can help answer theoretical questions.

Reliability estimates for psychological tests are almost always reported for nonclinical populations (e.g., the normative samples). Such practice will no longer be sufficient as the new standards for testing call for an adequate assessment of psychometric properties within the specific population being tested. The purpose of this study was to provide internal consistency reliability estimates for clinical groups on the Wechsler Adult Intelligence Scale–Third Edition. The study included data from 403 clinical participants composed of 10 groups of adults recruited as part of the WAIS–III clinical validity studies. Split-half reliability coefficients were obtained for these groups replicating the procedure used in the WAIS–III. With 8 of the clinical groups, the split-half reliability coefficients were comparable to, or even higher than, those reported for the WAIS–III standardization sample. In general, the split-half coefficients for the Verbal subtests tended to be higher than the coefficients for the Performance subtests. The high magnitude and general pattern of these coefficients demonstrate that the WAIS–III scales do not include additional error variance above and beyond what is reported in the WAIS–III–WMS–III Technical Manual when it was used to assess certain clinical groups. For the ADHD/ADD and learning disabilities groups, however, the internal consistencies coefficients of some subtests were relatively lower, although not statistically significant, than the normative sample. These findings may reflect more heterogeneity within the groups. The implications for assessment and for using alternate methods of determining the psychometric properties in these populations are discussed. (JINS, 2001, 7, 862–866.)

This study explored the neurodiagnostic utility of 6 factor scores identified by recent exploratory and confirmatory factor analyses of the WAIS–III and WMS–III: Verbal Comprehension, Perceptual Organization, Processing Speed, Working Memory, Auditory Memory and Visual Memory. Factor scores were corrected for age, education, sex and ethnicity to minimize their influences on diagnostic accuracy. Cut-offs at 1, 1.5 and 2 standard deviations (SDs) below the standardization sample mean were applied to data from the overlapping test normative samples (N = 1073) and 6 clinical samples described in the WAIS–III/WMS–III Technical Manual (N = 126). The analyses suggest that a 1 SD cut-off yields the most balanced levels of sensitivity and specificity; more strict (1.5 or 2 SD) cut-offs generally result in trading modest gains in specificity for larger losses in sensitivity. Finally, using combinations of WAIS–III/WMS–III factors together as test batteries, we explored the sensitivity and specificity implications of varying diagnostic decision rules (e.g., 1 vs. 2 impaired factors = “impairment”). For most of the disorders considered here, even a small (e.g., 3 factor) WAIS–III/WMS–III battery provides quite good overall diagnostic accuracy. (JINS, 2001, 7, 867–874.)

Since memory performance expectations may be IQ-based, unidirectional base rate data for IQ-Memory Score discrepancies are provided in the WAIS–III/WMS–III Technical Manual. The utility of these data partially rests on the assumption that discrepancy base rates do not vary across ability levels. FSIQ stratified base rate data generated from the standardization sample, however, demonstrate substantial variability across the IQ spectrum. A superiority of memory score over FSIQ is typical at lower IQ levels, whereas the converse is true at higher IQ levels. These data indicate that the use of IQ–memory score unstratified “simple difference” tables could lead to erroneous conclusions for clients with low or high IQ. IQ stratified standardization base rate data are provided as a complement to the “predicted difference” method detailed in the Technical Manual. (JINS, 2001, 7, 875–880.)

The utility of the WMS–III in detecting lateralized impairment was examined in a large sample of patients with temporal lobe epilepsy. Methods of analysis included evaluation of group means on the various indexes and subtest scores, the use of ROC curves, and an examination of Auditory–Visual Index discrepancy scores. In addition, performance on immediate and delayed indexes in the auditory and the visual modality was compared within each group. Of the WMS–III scores, the Auditory–Visual Delayed Index difference score appeared most sensitive to side of temporal dysfunction, although patient classification rates were not within an acceptable range to have clinical utility. The ability to predict laterality based on statistically significant index score differences was particularly weak for those with left temporal dysfunction. The use of unusually large discrepancies led to improved prediction, however, the rarity of such scores in this population limits their usefulness. Although the utility of the WMS–III in detecting laterality may be limited in preoperative cases, the WMS–III may still hold considerable promise as a measure of memory in documenting baseline performance and in detecting those that may be at risk following surgery. (JINS, 2001, 7, 881–891.)

The criterion validity of the new subtests from the Wechsler Adult Intelligence Scale–Third Edition (WAIS–III; Wechsler, 1997) was evaluated in a sample of 100 patients with traumatic brain injury (TBI). Letter–Number Sequencing and Symbol Search, but not Matrix Reasoning, yielded statistically significant differences in performance between patients with moderate–severe TBI, patients with mild TBI, and demographically matched controls. Level of education accounted for a statistically significant amount of variance in the performance of patients with TBI, in addition to that explained by injury severity variables. It is concluded that Letter–Number Sequencing and Symbol Search have satisfactory criterion validity, but that they need to be supplemented with other measures in the context of neuropsychological evaluations. Matrix Reasoning, on the other hand, is not sensitive to the sequelae of TBI and more studies are needed to determine how it can be used for neuropsychological assessment purposes. (JINS, 2001, 7, 892–898.)

Aristotle was right: Give me a fixed point, and I will move the earth. The “earth” in this case is the urban, semiliterate, nontestwise patient, in particular from South Africa, with symptoms of mild or moderate head trauma and in need of neuropsychological assessment. The “fixed point” does not exist in the form of test given being the same as test received conceptually with valid norms to go with it. How then can we move the earth? With justice done to psychometric requirements and most importantly, to the mental abilities of the patient, we can not. The neuropsychological tests normed on Western subjects within the Western cultural sphere, has put this patient to a disadvantage.

This book represents the latest effort to summarize a field that has grown exponentially. As stated in the introduction to the book, the contentious nature of forensic neuropsychology has resulted in a range of opinion among even the most seasoned neuropsychologists. Consequently, I must be absolved for offering what may seemingly be a partisan slant in this review.

Alan Baddeley's delightful new book is another in the series “Cognitive Psychology: A Modular Course” and as such its purpose is to bring together research relevant to the topic of memory in a format that can be easily understood by undergraduate psychology students. It certainly achieves this aim, but will also be of interest to a wide range of readers, from the interested layperson to the experienced psychologist. Memory holds an important place in everyone's lives, and readers on the far side of middle-age may find this book particularly pertinent, and in most cases reassuring! Academic and professional psychologists from many different subdisciplines will find this an easy book to refer to when they want to refresh or update their memory about one or other aspect of memory. Likewise researchers and professionals from other disciplines such as neuroscience or medicine will find this book a gold-mine of information, both academic and practical.

Sexual Differentiation of the Brain will appeal primarily to researchers with specific interest in neuroendocrinological contributions to the sexual dimorphism of brain structures and neuropathways, predominantly in nonhumans. Collectively, the 16 chapters provide comprehensive review of our current understanding of the effects of hormonal steroids and their metabolites on brain development and the manner in which this correlates with specific behavioral functions. The clinician interested in furthering an understanding of sexually differentiated cognitive functioning or behavioral patterns in humans, may perceive discussion in many chapters as esoteric at best, or less charitably, as irrelevant. It is assumed that the reader has a prerequisite understanding of basic genetic and hormonal influences on brain development and subsequent behavioral manifestation. Although these issues are clarified by reference or associated discussion in several chapters, an introductory overview by the editor would have been beneficial. Similarly, the editor would have facilitated the reader's effort by organizing chapters according to findings of brain sexual dimorphism in humans versus “primitive” species, by clarifying the relevance of examining other species and/or by focusing attention to parallels in anatomical findings or in associated behavior.

Neuropsychologists are placed in an increasing number of situations where they must provide empirical evidence of the validity of their methods. Managed care companies want to know the bottom line of whether a given assessment will have any impact on the patient's medical or psychological care. Expert witnesses are asked increasingly to provide scientific facts regarding the tests used in their assessment battery. Grant review committees inquire about the probability that a given test will yield a significant finding when used with a particular clinical population. It is argued that there is little empirical information available to aid in making these decisions. The volume Neuropsychological Differential Diagnosis by Zakzanis, Leach, and Kaplan takes an initial step in providing this type of information.