This study examined the impact of irrelevant dimensional variation on rule-based category learning in patients with Parkinson's disease (PD), older controls (OC), and younger controls (YC). Participants were presented with 4-dimensional, binary-valued stimuli and were asked to categorize each into 1 of 2 categories. Category membership was based on the value of a single dimension. Four experimental conditions were administered in which there were zero, 1, 2, or 3 randomly varying irrelevant dimensions. Results indicated that patients with PD were impacted to a greater extent than both the OC and YC participants when the number of randomly varying irrelevant dimensions increased. These results suggest that the degree of working memory and selective attention requirements of a categorization task will impact whether PD patients are impaired in rule-based category learning, and help to clarify recent discrepancies in the literature. (JINS, 2005, 11, 503–513.)

As many as 50% of multiple sclerosis (MS) patients experience clinical or subclinical depression. A voluminous literature has documented affective memory biases (AMB) among depressed individuals. Despite this, little is known regarding how depressive symptoms may affect MS patients' ability to recall positive and negative material. The present study employed an affective list-learning task that increased cognitive load and inhibited the use of higher order encoding strategies. The purpose of the study was twofold: to determine whether MS patients exhibit AMB and to examine whether subvocal repetition and other higher order encoding strategies are essential to the formation of AMB among people experiencing depression. Results indicated a strong relationship between depression and AMB in MS. The results are discussed in relation to existing biological research that indicates limbic and/or other subcortical systems may play a role in the formation of AMB. (JINS, 2005, 11, 514–521.)

The objective of this study was to carry out a detailed investigation of the neurological, neuropsychological, and return-to-work status of treatment for unruptured intracranial aneurysms (UIAs). A prospective design was used to evaluate the outcome of UIA treatment in a group of 26 UIA patients. Over a 24-month period UIA patients were assessed prior to treatment, during hospitalization, at three months and at six months following treatment. Their performance was compared to a group of 20 matched controls. Neurological morbidity as a result of the UIA treatment was 5%, as assessed by the Glasgow Outcome Scale (GOS) or Rankin at 3 months. The Telephone Interview for Cognitive Status (TICS) proved to be unreliable as a measure of cognitive change. Reliability of change analysis was more sensitive than group analysis, and revealed a pattern of cognitive deficits in 10% of patients as a result of the UIA treatment. In addition, 25% of patients reported a change in work role as a result of the UIA treatment. While 10% of patients sustained mild to moderate neurological and cognitive impairments 3 to 6 months following UIA treatment, their deficits were not as wide-ranging nor as severe as those sustained by patients who survive a subarachnoid hemorrhage (SAH). (JINS, 2005, 11, 522–534.)

Background: Divergences in cognitive disturbances in hypothyroidism reported in the literature are a result of a methodological bias. Methods: By using a precise methodology, we examined attention and executive functions in hypothyroidism, verified the presence of anxiety and depressive symptoms in hypothyroidism, and examined the possible link between these symptoms and the cognitive disturbances (searching for attentional bias for words with a negative emotional valence). We administered a battery of cognitive tests to 23 participants who had undergone thyroidectomy for thyroid carcinoma: for the first time in an euthyroid state, then 3 weeks later (still in the euthyroid state) to assess the test/retest effect, and finally 4 weeks later in an hypothyroid state. We compared their performance with that of a group of 26 control participants who were also administered the same cognitive tests, also 3 times. Results: In hypothyroidism, the thyroid participants were more anxious and depressed than the controls and presented attentional and executive disturbances that reflected general slowing and difficulties in using their capacities of inhibition. However, they did not exhibit an attentional bias for words with a negative emotional valence. Conclusions: Contrary to what was expected, symptoms of anxiety and not symptoms of depression interfered with the cognitive performance of participants in hypothyroidism. (JINS, 2005, 11, 535–544.)

Two experiments were carried out to examine memory in persons with amnesia using self-performed tasks. In Experiment 1, persons with Korsakoff's syndrome and nonamnesic participants with alcoholism learned action phrases not involving real objects by either self-performed tasks or verbal tasks. As indexed by free recall and recognition tests, a memory advantage favoring self-performed tasks was confirmed in both participant groups. In Experiment 2, persons with Korsakoff's syndrome, nonamnesic alcoholic participants, and young control participants learned object names under three different study conditions that differed from one another as to whether actions for each name were verbally generated and whether actions actually were performed. Verbal generation with or without performing the action facilitated recognition, whereas recall advantage was found only in the verbal generation-plus performance condition. These findings confirm a comparable memory advantage of self-performed tasks for a group with Korsakoff's syndrome and a group of nonamnesic comparison participants. Action memory therefore has potential therapeutic implications for memory rehabilitation. (JINS, 2005, 11, 545–553.)

Treatment for childhood acute lymphoblastic leukemia (ALL), which includes CNS prophylaxis, is associated with central and peripheral neurotoxicity. The purpose of the present study was to analyze the effects of chemotherapy on various levels of visuomotor control in survivors of childhood ALL treated without cranial irradiation, and to identify risk factors for possible deficits. Visuomotor function was compared between children after treatment for ALL (n = 34), children after treatment for Wilms tumor, which consists of non-CNS directed chemotherapy (n = 38), and healthy controls (n = 151). Three tasks were administered: a simple visual reaction time task and two tasks measuring visuomotor control with one requiring a higher level of cognitive control than the other. Visuomotor deficits were detected only in the ALL group, with poorer performance restricted to the condition requiring the highest level of control. Significant risk factors for poorer performance were female gender and a short time since end of treatment, and a trend was found for a young age at diagnosis. A high cumulative methotrexate dose was an adverse predictive factor in girls. The results indicate that chemotherapy-induced central neurotoxicity in childhood ALL treatment is associated with higher order visuomotor control deficits. Girls appear to be particularly vulnerable. (JINS, 2005, 11, 554–565.)

Ten amnesic patients of various etiologies and 10 matched normal controls participated in this study. On 2 consecutive days, subjects studied 30 novel word–word associations 6 times. Using a cued recall task, we assessed episodic learning and delayed retention of the study material immediately after each study phase and again 24 hr after the final study phase. Further, we evaluated implicit memory for new between-word associations by means of an automatic relational priming paradigm immediately after the delayed cued recall trial. Amnesic patients performed poorly on the cued recall task. Moreover, in the overall group of amnesics the priming effect failed to reach statistical significance. When the overall group of amnesics was split according to mean performance on the cued recall task, those in the low performer subgroup—comprised of 6 patients with direct or indirect involvement of the hippocampi—were particularly poor at episodically remembering the associations and did not reveal any relational priming. These data support the hypothesis of similar impairment of new episodic and implicit learning in amnesic patients and suggest that the hippocampus is crucial for both kinds of new learning. (JINS, 2005, 11, 566–573.)

Although numerous studies have shown that brain-damaged patients tend to underestimate neuropsychological (NP) impairment when self-ratings are compared to informant ratings, the meaning of such discrepancies is not well studied in multiple sclerosis (MS). We compared patient self- and informant-report questionnaire ratings of NP functioning in 122 MS patients and 37 age- and education-matched normal controls. In addition to completing the Multiple Sclerosis Neuropsychological Questionnaire (MSNQ), participants underwent NP testing and assessment of depression, personality, and neuropsychiatric symptoms. Based on the normal distribution of discrepancy scores, patients were classified according to whether they overestimated or underestimated their cognitive ability, relative to informant ratings. ANOVAs comparing test scores derived from overestimators, underestimators, and accurate estimators were significant for multiple measures of cognitive function, depression, personality, and neuropsychiatric symptoms. Overestimators were characterized by less depression and conscientiousness, and greater degrees of cognitive impairment, euphoric behavioral disinhibition, and unemployment as compared to underestimators. We conclude that patient/informant discrepancy scores on the MSNQ are associated with the aforementioned neuropsychiatric features, and that the MSNQ has potential utility for predicting euphoria and disinhibition syndromes in MS. (JINS, 2005, 11, 574–583.)All authors are from the State University of New York (SUNY) at Buffalo School of Medicine, Department of Neurology, Division of Departmental and Behavioral Neurosciences, and the Jacobs Neurological Institute, Buffalo General Hospital, Buffalo, NY.

One of the most common chromosomal deletions is a loss of genetic material from the long arm of chromosome 18. Most individuals with this condition exhibit mental retardation (68%), yet previous attempts to link cognitive status to deletion size have not shown an association, possibly because cases with additional genetic abnormalities were included. We studied 46 participants ranging from 3 to 35 years of age who had a pure genetic abnormality by excluding those with mosaicism or complex genetic rearrangements. Our patients had terminal deletions ranging from a proximal breakpoint at 18q21.1 (greater genetic abnormality, larger deletion size) to a more distal breakpoint at 18q23 characterized with molecular genetic techniques. Cognitive ability, assessed with the age-appropriate measure (Bayley, 1993, Differential Ability Scale, Wechsler Scales), ranged from IQ = 49 to 113, with a predominance of mild and moderate mental retardation. Using multivariate regression, deletion size breakpoint rank order was predicted by cognitive ability, age, and adaptive behavior (Vineland Adaptive Behavior Scales), accounting for 36% of the variance in deletion size. However, lower cognitive ability (beta = .34, p = .032) and younger age (beta = .296, p = .024) predicted a larger deletion size, but adaptive behavior (beta = .225, p = .15) did not. An additional multivariate regression showed that cognitive ability and age together accounted for 33% of the variance in deletion size, whereas univariate regression showed that cognitive ability accounted for 26% of the variance and age accounted for 11% of the variance. These findings suggest that degree of cognitive impairment is associated with genetic abnormality when a large sample of individuals with “pure” deletions of genetic material from chromosome 18 is examined. (JINS, 2005, 11, 584–590.)

Studies have shown that parkinsonian signs are related to cognitive function in aging. What remains unclear is whether this association is stronger for some cognitive domains than it is for others, and precisely how much variability in global and specific cognitive functions is explained by the motor signs. We examined the associations between four parkinsonian signs (gait, rigidity, bradykinesia, tremor) and five cognitive domains (episodic memory, semantic memory, working memory, perceptual speed, visuospatial ability) in a large cohort of older persons who were free of Parkinson's disease and dementia and were participating in the Rush Memory and Aging Project. In a series of regression equations that controlled for age, sex, and education, higher levels of three signs (gait, rigidity, and bradykinesia) were related to lower levels of cognitive function, but they accounted for less than 5% of the variance in most measures. The results did not change when the presence of depressive symptoms, diabetes, and hypertension were added to the models. The cross-sectional association between parkinsonian signs and cognitive function did not vary substantially across specific cognitive domains or specific cognitive tests. The results suggest that parkinsonian signs have a modest, but statistically reliable, association with level of cognitive function in old age. (JINS, 2005, 11, 591–597.)

Visuoconstructional ability is an important domain for assessment in dementia. Use of graphomotor measures dominate this area; however, participants with low education produce results that cannot be easily interpreted. Our objective was to develop and validate a nongraphomotor assessment of visuoconstructional ability for use in dementia evaluations in persons with low or no education. In a longitudinal, population-based study of dementia among Yoruba residents of Ibadan, Nigeria aged 65 years and older, participants underwent clinical assessment with a battery of cognitive tests and consensus diagnosis. Performance on two visuoconstructional tests, Constructional Praxis and Stick Design, were compared. Gender, age, and education affected performance on both tests. The Stick Design test was more acceptable than Constructional Praxis as measured by the number of participants with total test failure (3.9% vs. 15.1%). The Stick Design test was significantly more sensitive to cognitive impairment and dementia than the Constructional Praxis test. We conclude that Stick Design is a reasonable test of visuoconstructional ability in older cohorts with very limited educational exposure and literacy. (JINS, 2005, 11, 598–605.)

Traditional neuropsychological measures of executive dysfunction (ED) are widely believed to lack adequate sensitivity and selectivity. This may indicate that existing measures are poorly designed and constructed, although an alternative explanation is that executive cognition is multifactorial, such that its assessment necessarily requires administration of multiple measures. This possibility led to the development of a test battery, the Behavioural Assessment of the Dysexecutive Syndrome (BADS). To investigate the sensitivity of the BADS to ED, it and various other measures of ED were administered to 64 persons who had sustained traumatic brain injury. The treating clinical neuropsychologist and occupational therapist for each participant also completed a behavioural rating scale, the Dysexecutive Questionnaire (DEX). Four factors were found to underlie scores on the neuropsychological measures, but few tests were sufficiently powerful to make a significant unique contribution to predicting scores on the DEX. This confirms that multiple tests, drawn from both the BADS and other sources, may be necessary to detect ED in a clinical population. (JINS, 2005, 11, 606–613.)

The relation between self-reported cognitive dysfunction and neuropsychological performance over 24 weeks was assessed in a sample of 53 multiple sclerosis patients. Subjects were assessed at Weeks Zero and 24 as part of a clinical trial to enhance cognition. At baseline, subjects had at least mild cognitive impairment on the Rey Auditory Verbal Learning Test and an absence of depression. Neuropsychological performance was assessed with a modification of the well standardized Brief Repeatable Battery. The 5-item Perceived Deficits Questionnaire and a 2-item memory and attention/concentration questionnaire assessed self-perceived cognitive impairment. Self-assessed cognition did not correlate with neuropsychological performance at either baseline or 24 weeks. However, changes in the self-assessment measures did correlate with changes in neuropsychological performance. Patients accurately perceived some changes in their level of cognitive dysfunction, though they were insensitive to the degree of their current dysfunction. Possible explanations of this pattern of results are discussed. (JINS, 2005, 11, 614–619.)

This study examined the validity of the Spanish and English Neuropsychological Assessment Scales (SENAS) in comparison with clinical diagnosis of normal cognition versus cognitive impairment, not demented (CIND) versus demented in elderly Hispanics and Whites. Relationships between SENAS scales and diagnosis were essentially the same in Hispanics and Whites. Verbal memory measures were most strongly related, with more than 35% of the variance in these measures accounted for by diagnosis independent of effects of education, age, gender, and language. Diagnosis accounted for more than 10% of the variance (19% on average) in 11 of the 17 measures examined in this study. Logistic regressions showed that verbal memory was important both for distinguishing normal from CIND and CIND from demented. Object naming improved discrimination of CIND from demented beyond that of verbal memory alone. These results provide evidence of equivalent validity across Hispanics and Whites. (JINS, 2005, 11, 620–630.)

Recent studies have described neuromaturation and cognitive development across the lifespan, yet few neuroimaging studies have investigated task-related alterations in brain activity during adolescence. We used functional magnetic resonance imaging (fMRI) to examine brain response to a spatial working memory (SWM) task in 49 typically developing adolescents (25 females and 24 males; ages 12–17). No gender or age differences were found for task performance during SWM. However, age was positively associated with SWM brain response in left prefrontal and bilateral inferior posterior parietal regions. Age was negatively associated with SWM activation in bilateral superior parietal cortex. Gender was significantly associated with SWM response; females demonstrated diminished anterior cingulate activation and males demonstrated greater response in frontopolar cortex than females. Our findings indicate that the frontal and parietal neural networks involved in spatial working memory change over the adolescent age range and are further influenced by gender. These changes may represent evolving mnemonic strategies subserved by ongoing adolescent brain development. (JINS, 2005, 11, 631–644.)

Although the development of Attention Deficit Hyperactivity Disorder (ADHD) after traumatic brain injury (TBI) has been described, it is unknown whether children with TBI and ADHD have greater neuropsychological impairments than children with TBI alone. This study examines attention, executive functioning, and memory in children with TBI-only and TBI + ADHD. Caregivers of 82 children with severe TBI completed structured psychiatric interviews at enrollment to diagnose premorbid ADHD and one-year after injury to diagnose post-injury ADHD. Children underwent neuropsychological testing one year after injury. One memory measure significantly differentiated children with TBI-only from children with newly developed ADHD [secondary ADHD (S-ADHD)] and those with premorbid ADHD that persisted after injury [persisting ADHD (P-ADHD)]. Compared with the TBI-only group, children with TBI + ADHD had worse performance on measures of attention, executive functioning, and memory. Results reveal that in children with severe TBI, the behavioral diagnosis of ADHD is associated with more difficulty in attention, executive functioning, and memory. Additionally, results suggest greater deficits in memory skills in the S-ADHD group compared with the P-ADHD group. Although findings provide preliminary support for distinguishing P-ADHD from S-ADHD, further research is needed to investigate neuropsychological differences between these subgroups of children with severe TBI. (JINS, 2005, 11, 645–653.)

Semantic Cognition: A Parallel Distributed Processing Approach, by Timothy T. Rogers and James L. McClelland. (2004). Cambridge, MA: MIT Press, 425 pp., $50.00/£32.95.

This book is aimed at all scientists interested in semantic cognition, even those with limited experience of computational modeling. It benefits from concise and logically presented text and the effective use of figures and illustrations, with details of simulations tucked away in the Appendix. The length of the book defines it not only as a useful addition to a reference collection, but also an excellent primer for young researchers, postgraduates, and even advanced undergraduates.

Stress, the Brain and Depression, by Herman M. van Praag, Ron de Kloet, and Jim van Os. (2004). Cambridge, UK: Cambridge University Press. 293 pp., $110.00, £65.00.

This book addresses one of the fundamental questions in the etiology of depression: Does stress cause depression? Although intuitively one may answer yes to this question, the book presents detailed psychological and neurobiological evidence to show the complexity of the issue. The book focuses on three major themes: (1) pathophysiology of stress in depression; (2) stress-inducible subtypes of depression; and (3) diagnosing depression to understand biological underpinnings of the condition. Although each of the three authors wrote individual chapters (with van Praag writing most chapters), the book is well organized and flows smoothly. The book is well written in an entertaining style, especially the chapters written by van Praag. For example, when discussing the problems with the current DSM-IV diagnostic system, van Praag states, “psychiatric diagnosing is locked up in a nosological straightjacket, and thus immobilized” (p. 8). It is this type of commentary, sprinkled throughout the book, that holds the reader's interest. In addition, the authors provide a fresh perspective on diagnostic issues in depression, stress/negative life events, and the neurobiology of depression. I expect the volume will stimulate research ideas. To get the most out of the book, it should be read in its entirety. Exceptions are the chapters reviewing the psychobiology of stress and depression, which provide very comprehensive summaries of the research literature, and may serve as a good reference. The initial chapters build the theoretical foundation for the presentation of the biological data, and the final chapters integrate the biological data with the initial hypotheses. The authors take issue with diagnostic trends in psychiatry, definitions of stress and life events, and to a lesser extent, neurobiological approaches to psychiatric research. The authors do not rehash old findings, but include the most recent literature. For example, when discussing corticotrophin releasing hormone (CRH) receptors, they present new findings supporting a possible parallel parasympathetic-related system in addition to the traditional sympathetic response. When the data presentation becomes complex, information is summarized in easy-to-read tables.

Developmental Motor Disorders: A Neuropsychological Perspective. Deborah Dewey and David E. Tupper (Eds.). (2004). New York: Guilford, 501 pp., $70.00.

This book is thorough, thoughtful, and uniquely useful in the questions it asks and attempts to answer. Included, for example, are discussions of problems associated with the use of traditional neurological “soft signs” to detect and predict long-term motor impairment; patterns of newborn movement that predict childhood cerebral palsy; strengths and weaknesses of tests and observational checklists to assess motor proficiency; how best to diagnose and treat phonological disorders versus verbal apraxia, or dysgraphia versus motor dyspraxia; analysis and treatment of handwriting problems; brain systems that subserve proprioception and how these systems develop or derail; neuroimaging that assists in making the diagnosis of periventricular leukomalacia; and, treatment approaches for children with Developmental Coordination Disorder.