The prefrontal cortex of the brain has been shown to play a crucial role in working memory, and age-related changes in prefrontal function may contribute to the improvements in working memory that are observed during childhood. We examined the developmental trajectory of working memory in school-age children with early-treated phenylketonuria (PKU), a metabolic disorder that results in prefrontal dysfunction. Using a recognition procedure, we evaluated working memory for letters, abstract objects, and spatial locations in 20 children with PKU and 20 typically developing control children. Children in both groups ranged from 6 to 17 years of age. Our findings revealed poorer performance across all three types of materials for children with PKU. In addition, there was a significant difference in the developmental trajectory of working memory for children with PKU as compared with controls. Specifically, deficits were not apparent in younger children with PKU. Instead, deficits were observed only in older children, suggesting the presence of a developmental deficit rather than a developmental delay in the working memory of children with PKU. (JINS, 2002, 8, 1–11.)

The presence of cocaine during the prenatal period disrupts the development of neural systems involved in mediating visual attention; therefore, it is possible that prenatal cocaine exposure results in impairments in visual attention in early childhood. In the current study we hypothesized that preschool children with prenatal cocaine exposure would exhibit difficulties in the disengagement operation of visual attention and in sustaining attention, particularly for targets presented in the right visual field. Fourteen cocaine-exposed children and 20 control children between 14 and 60 months of age were assessed on measures of visual attention, cognition, and behavior. Cocaine-exposed children had slower reaction times on disengagement trials in the second half of our attention task, supporting our hypotheses that impairments in disengagement and sustained attention are associated with prenatal cocaine exposure. There was a trend for slower reaction times to targets presented in the right visual field, but not to targets presented in the left visual field. Cocaine-exposed children also exhibited greater difficulties in behavioral regulation. Overall, our findings suggest that children with prenatal cocaine exposure demonstrate specific impairments in visual attention and behavioral regulation. (JINS, 2002, 8, 12–21.)

The planum temporale is clearly involved in language processing, for it serves as the auditory association cortex. Research has consistently demonstrated that 60 to 70% of the population has leftward asymmetry of the planum temporale. Research has also suggested that dyslexic individuals tend to have either rightward asymmetry or symmetrical plana. Moreover, many studies have found a relationship between the presence of dyslexia and/or language impairment and deficits in the normal right ear advantage found in dichotic listening paradigms. In this context, this study examined the relationship between planum temporale asymmetry and ear preference in dichotic listening performance in children with Developmental Dyslexia and Attention-Deficit/Hyperactivity Disorder (ADHD). Subjects included 19 children with dyslexia (10 of whom had a comorbid diagnosis of ADHD), 23 children with ADHD, and 12 diagnosed normal control children. Dichotic listening data were not collected for 8 of the 12 normal control children and for 3 of the 23 ADHD children. Results revealed no significant difference between ADHD and dyslexic subjects in regard to ear advantage on the free recall dichotic listening task. In addition, although the directed dichotic listening tasks were not related to degree of planum asymmetry, as predicted, results indicated that subjects who consistently displayed an atypical left ear advantage tended to have larger right bank lengths than those who consistently displayed a typical right ear advantage. These findings support the notion that some individuals with dyslexia or language deficits tend to have a larger right planum temporale and that performance on dichotic listening tasks may reflect this relatively unusual pattern. (JINS, 2002, 8, 22–36.)

A growing number of studies show postconcussion syndrome (PCS) symptom report is influenced by factors other than head injury, suggesting symptoms typically associated with PCS may not be specific to head injury. Given the role that symptom expectation has been hypothesized to play in PCS symptom etiology, a comparison of symptoms expected for various disorders seems overdue. The present study asked 82 undergraduates to report the symptoms they currently experience, and then to report the symptoms they would expect to experience if they had had suffered either a head injury, an orthopedic injury, posttraumatic stress, or depression. No current differences in overall symptoms or in symptom subscales emerged. Results showed individuals portraying head injury, posttraumatic stress, and depression expected an increase in total symptoms, though individuals portraying an orthopedic injury did not expect such an increase. Results also showed simulators of head injury, posttraumatic stress, and depression expected equivalent rates of overall symptoms, memory/cognitive complaints, somatic concerns, and distracter symptoms, though head-injured individuals reported fewer affective symptoms than those portraying psychological disorders. In all, these findings suggest that individuals have a relative lack of specificity in symptom expectation for various disorders, with the implication that symptom checklists for “PCS” may not be useful for diagnosis. (JINS, 2002, 8, 37–47.)

Findings from a recent population-based survey indicate that about 33% of patients with dementia reside alone. Because many of these patients may not have a caregiver who visits them regularly, the need for a neuropsychological (NP) test to predict patients' functional competence to live alone safely is evident. In this study, we compared the accuracy of predicting Instrumental and Basic Activities (IADLs and ADLs) of 22 patients with Alzheimer's disease using several standard NP tests and the newly developed Problems in Everyday Living (PEDL) test. Performance of IADLs and ADLs as rated by caregivers was significantly correlated with performance on the PEDL, the Mini-Mental State Exam (MMSE), and with the Shipley Institute of Living Test of Verbal Abstraction (SILS-A), but not with vocabulary or naming. The PEDL was the best predictor of IADL scores (r = 0.71), compared to the MMSE (r = 0.52) and the SILS-A (r = 0.57), while the MMSE was the best predictor of ADL performance (r = 0.69), compared to the PEDL (r = 0.58) and the SILS-A (r = 0.50). (JINS, 2002, 8, 48–57.)

Subjects underwent longitudinal neuropsychological assessment in order to retrospectively determine which measures of cognitive function best predicted later development of dementia of the Alzheimer type (DAT). Three groups of subjects were studied: normal controls, patients with early DAT, and questionable dementia subjects (QD). All subjects were assessed using a battery of standard neuropsychological measures and two subtests from the Cambridge Neuropsychological Test Automated Battery (CANTAB), paired associate learning and delayed matching to sample. A structured interview was also used to elicit a profile of the subject's daily functioning. Subjects were assessed every 6 months for 2 years. At the 6 month assessment, almost half of the QD group exhibited significant deterioration in scores on the computerized paired associate learning subtest, while maintaining their scores on standard measures. At the conclusion of the study, all of this QD subgroup fulfilled the NINCDS–ADRDA criteria for probable DAT pertaining to significant cognitive and functional deterioration. Performance on the CANTAB paired associate learning subtest identified the onset of progressive memory deterioration in a subgroup of QD subjects. In almost all cases this was well before significant deterioration was noted on standard neuropsychological measures. Paired associate learning performance may therefore be a valuable tool for the early, preclinical detection and assessment of DAT. (JINS, 2002, 8, 58–71.)

Children with hydrocephalus have poor math skills. We investigated the nature of their arithmetic computation errors by comparing written subtraction errors in good readers with hydrocephalus, typically developing good readers of the same age, and younger children matched for math level to the children with hydrocephalus. Children with hydrocephalus made more procedural errors (although not more fact retrieval or visual–spatial errors) than age-matched controls; they made the same number of procedural errors as younger, math-level matched children. We also investigated a broad range of math abilities, and found that children with hydrocephalus performed more poorly than age-matched controls on tests of geometry and applied math skills such as estimation and problem solving. Computation deficits in children with hydrocephalus reflect delayed development of procedural knowledge. Problems in specific math domains such as geometry and applied math, were associated with deficits in constituent cognitive skills such as visual spatial competence, memory, and general knowledge. (JINS, 2002, 8, 72–82.)

Deficits on tasks requiring semantic memory in Alzheimer's disease (AD) may be due to storage loss, a retrieval deficit, or both. To address this question, we administered multiple tasks involving 9 exemplars of the category “animals,” presented as both words and pictures, to 12 AD patients and 12 nondemented individuals. Participants made semantic judgments by class (sorting task), similarity (triadic comparison task), and dimensional attributes (ordering task). Relative to control participants, AD patients were impaired on an unstructured sorting task, but did not differ on a constrained sorting task. On the triadic comparison task, the patients were as likely to make judgments based on size as domesticity attributes, whereas control participants made judgments based primarily on domesticity. The patients' judgments were also less consistent across tasks than those of control participants. On the ordering tasks, performance was generally comparable between groups with pictures but not words, suggesting that pictures enable AD patients to access information from semantic memory that is less accessible with lexical stimuli. These results suggest that AD patients' semantic judgments are impaired when the retrieval context is unstructured, but perform normally under supportive retrieval conditions. (JINS, 2002, 8, 83–94.)

Children with spina bifida and hydrocephalus (SBH) have long been known to have difficulties with visual perception. We studied how children with SBH perform 12 visual perception tasks requiring object identification, multistable representations of visual space, or visually guided overt actions. Four tasks required object-based processing (visual constancy illusions, face recognition, recognition of fragmented objects, line orientation). Four tasks required the representation of visual space in egocentric coordinates (stereopsis, visual figure-ground identification, perception of multistable figures, egocentric mental rotation). Four tasks required the coupling of visual space to overt movement (visual pursuit, figure drawing, visually guided route finding, visually guided route planning). Effect sizes, measuring the magnitude of the difference between SBH children and controls, were consistently larger for action-based than object-based visual perception tasks. Within action-based tasks, effect sizes were large and roughly comparable for tasks requiring the representation of visual space and for tasks requiring visually guided action. The results are discussed in terms of the physical and brain problems of children with SBH that limit their ability to build effective situation models of space. (JINS, 2002, 8, 95–106.)

Most patients with neglect demonstrate a crossover effect on line bisection. Crossover refers to a pattern of performance in which long lines (>10 cm) are bisected ipsilateral to brain injury and short lines (<2 cm) are bisected contralateral to brain injury. Crossover bisections on short lines are of interest because they are not predicted by contemporary theories concerning neglect. However, we propose that the effect depends on two independent factors that normally influence bisection performance but are merely exaggerated in neglect—a tendency to overestimate the length of short lines and underestimate long lines and a tendency to orient attention preferentially in one spatial direction. We predicted that both patients with unilateral left and right hemisphere injury would demonstrate crossover on line bisection and that they would overestimate short lines and underestimate long lines upon direct visual inspection. Further, the 2 groups were predicted to demonstrate crossover in opposite directions owing to different lesion-induced biases in attentional orientation. Testing 5 patients with right hemisphere injury and 7 patients with left hemisphere injury confirmed each prediction. Additionally, errors in length estimation were exaggerated among patients with right hemisphere injury, most of whom had neglect. It is concluded that while crossover is accentuated in cases of neglect, it is not a consequence of neglect per se. As such, crossover bisections are not at odds with contemporary neglect theory. (JINS, 2002, 8, 107–114.)

It is now generally accepted that central nervous system treatments for childhood cancer can result in significant cognitive impairment, most commonly in the areas of attention/concentration. We review the literature on attentional and neurocognitive deficits in this population, and also efforts to remediate attentional deficits in other brain injured populations. It was our goal to develop an innovative, psychologically based outpatient rehabilitation program that would improve dysfunctional attentional processes and associated neuropsychological deficits. The characteristics of this program and a pilot study of its effectiveness are described. Participants were 31 off-therapy cancer survivors with documented attention deficits. Twenty-one completed the cognitive remediation program (CRP) and 10 served as comparisons. All participants completed a test of vigilance attention, 2 tests with an attentional component, and an arithmetic academic achievement measure. When the scores of the 2 groups were compared, the CRP group exhibited statistically significant improvement on all attentional measures. In contrast, the comparison group did not manifest any significant changes. Neither group demonstrated statistically significant changes on the arithmetic achievement test. We believe that the CRP has potential for improving attention/concentration, but generalization to academic achievement remains unproven. Phase 3 clinical trials and the documentation of long-term treatment gains are needed. Furthermore, it will be necessary to demonstrate the ecological validity of the CRP. With these caveats, this therapeutic approach may be helpful in other populations of cognitively impaired children and young adults, such as patients who have suffered traumatic brain injury. (JINS, 2002, 8, 115–124.)

Essential tremor (ET) is the most common type of movement disorder, although its etiology and neurophysiological substrates remain unclear. While thought to be a benign condition, it has yet to be studied from a neuropsychological perspective. We examined the neurocognitive functioning of 13 nondemented subjects with severe ET, including aspects of memory, cognitive flexibility, and attention. Results revealed that 12/13 subjects demonstrated impairment on 1 or more cognitive measures in comparison with published normative data. The pattern of findings was suggestive of relative dysfunction of frontal-mediated processes not unlike that seen in Parkinson's disease. These deficits were found in subjects irrespective of the presence of cognitive complaints, depression, or the existence of other potential neurocognitive risk factors. These findings suggest that mild cognitive deficits are not uncommon in association with severe ET and may be related to subcortical systems. (JINS, 2002, 8, 125–129.)

The facial feedback hypothesis suggests that facial expressions are either necessary or sufficient to produce emotional experience. Researchers have noted that the ideal test of the necessity aspect of this hypothesis would be an evaluation of emotional experience in a patient suffering from a bilateral facial paralysis; however, this condition is rare and no such report has been documented. We examined the role of facial expressions in the determination of emotion by studying a patient (F.P.) suffering from a bilateral facial paralysis. Despite her inability to convey emotions through facial expressions, F.P. reported normal emotional experience. When F.P. viewed emotionally evocative slides her reactions were not dampened relative to the normative sample. F.P. retained her ability to detect, discriminate, and image emotional expressions. These findings are not consistent with theories stating that feedback from an active face is necessary to experience emotion, or to process emotional facial expressions. (JINS, 2002, 8, 130–135.)

Compiling a dictionary is a formidable undertaking. Noah Webster published the first American dictionary in 1806 and immediately set about revising it to his formidable An American Dictionary of the English Language published 22 years later in 1828. The next revision appeared in 1840. These timelines provide some estimate of the effort involved in such an undertaking.

John Richardson's straightforward text on imagery is another book in the series Cognitive Psychology: A Modular Course and as such its purpose is to bring together research relevant to the topic of imagery in a format that can be easily understood by undergraduate psychology students. This book will certainly fulfill this purpose, although it may be even more useful for the student at undergraduate or graduate level who wishes to gain an overview or refresher course on imagery research in enough detail to act as a basis for further and more in-depth reading. It may also provide ideas for graduate research projects; imagery seems to lend itself to small projects that can be fairly easily carried out on normal participants with minimal equipment or complex computer programming. As we all have some ability to generate and manipulate mental images, the topic is intrinsically fascinating; we are all keen to know whether we can generate this image or rotate that one. Thus, whilst reading the book, I found myself answering many of the questions given as examples of various imagery questionnaires (am I a visualizer or a verbalizer?), and seeing how vividly I could imagine a daffodil hidden inside the torch held up by the Statue of Liberty. I imagine this adds to the effectiveness of the book; certainly it is effective as a means of holding the reader's attention.

The aims of this book are grand indeed. Rolls addresses such questions as, What are emotions? Why do we have emotions? What are the rules by which emotion operates? What are the brain mechanisms of emotion, and how can disorders of emotion be understood? Why does it feel like something to have an emotion? Why is the brain built to have reward, and punishment, systems? How does the brain produce behavior by using reward, and punishment, mechanisms? And in fact he does succeed remarkably well in presenting a synthesis of experimental data to elucidate many of these questions.

This heroic undertaking, while it is not an exciting read, appears to be a necessary addition to the practicing clinician's reference shelf—the one that's within arm's reach while preparing a report. It is a dazzlingly comprehensive review of the literature, reporting on what looks to be just about every study involving a repeat examination published between 1970 and 1999.

While genetic linkages to a variety of disorders have been suspected for decades, it has only been relatively recently that these linkages have come to be understood to a greater degree. The search for the genetic basis of some neurodevelopmental disorders, such as learning disabilities, has been elusive and fraught with complex hurdles, the genetic basis of other neurodevelopmental disorders, such as Down syndrome, has been much more clear. Other childhood disorders, such as Turner syndrome and fragile X syndrome, also documented clearly defined genotypes. Even when a clear genetic contribution is known (i.e., the genotype), the exact neurobehavioral manifestations (i.e., the phenotypes) remain unclear or poorly documented for many disorders. This edited volume addresses this quest and, perhaps, provides one of the most comprehensive descriptions of the available literature in the interface between genetics and behavior in childhood. As noted by the editors, one of the major objectives of this text is to provide students, clinicians, and researchers with a working knowledge base of behavioral genetics. In this regard, the editors wanted to provide a comprehensive text that was “organized in a framework that is understandable and immediately useful in clinical practice” (p. 6).