Response bias reflects the decision rule an individual uses when faced with uncertainty on recognition memory tasks. Recent studies indicate frontal regions may mediate response bias performance. One theory of aging also implicates frontal lobe contributions in age-related cognitive changes. This suggests that frontal lobe changes may mediate response bias in older adults. Consistent with this frontal aging hypothesis, we predicted that response bias would become more liberal with age. Methods: Participants were 181 younger (30–49) and 112 older normal adults (75+) that were part of the California Verbal Learning Test-second edition (CVLT-2) normative sample (total n = 1078). We used parametric measures of discriminability and response bias provided by the CVLT-2 scoring program. Groups were similar in IQ and education. Multi-level regression models were created to examine the effects of moderating variables. The interaction between age and age group significantly predicted response bias. Post hoc analysis indicated that increasing age was associated with more liberal bias in the older but not in the younger group. In the light of reported relationships between frontal regions and both aging and response bias, we hypothesize that frontal changes may be the underlying mechanism explaining the increase in liberal response bias with age. (JINS, 2006, 12, 1–7.)

The aim of this investigation was to assess deficits in prospective remembering following chronic traumatic brain injuries (TBI), under conditions of high and low distraction. We constructed a virtual shopping precinct from photographs, sounds, and video segments linked together. The street was divided into halves, a low distraction zone and a high distraction zone (with increased visual and auditory noise). Twenty persons with TBI (7 severe, 7 very severe, 6 extremely severe) and 20 matched controls completed ongoing and prospective memory tasks while “walking” along the street. In the ongoing task, participants were given ten errands to complete with a checklist accessible at any time. The prospective component required responding to three targets that appeared repeatedly. As predicted, the TBI group performed both the ongoing and the prospective components of the street task poorly compared with the controls and was more affected by distractions. The results suggest that the real-life deficits in memory skills reported by persons with TBI may become more apparent when remembering engages executive processes and that computer simulations can be used to construct sensitive measures of practical memory abilities. (JINS, 2006, 12, 8–16.)

The clinical presentation of electrical injury commonly involves physical, cognitive, and emotional complaints. Neuropsychological studies, including case reports, have indicated that electrical injury (EI) survivors may experience a broad range of impaired neuropsychological functions, although this has not been clarified through controlled investigation. In this study, we describe the neuropsychological test findings in a series of 29 EI patients carefully screened and matched to a group of 29 demographically similar healthy electricians. Participants were matched by their estimated premorbid intellectual ability. Multivariate analysis of variance was used to assess group differences in the following neuropsychological domains: attention and mental speed, working memory, verbal memory, visual memory, and motor skills. EI patients performed significantly worse on composite measures of attention/mental speed and motor skills, which could not be explained by demographic differences, injury parameters, litigation status, or mood disturbance. Results suggest that cognitive changes do occur in patients suffering from electrical injury. (JINS, 2006, 12, 17–23.)

We assessed midsagittal corpus callosum size in sickle cell disease (SCD) and its relationship to lesion volume, lesion location, and cognitive functioning. Twenty-eight children with SCD and 16 demographic controls completed magnetic resonance imaging (MRI) and neuropsychological testing. Corpus callosum (CC) size was smaller for children with silent infarcts (n = 8) or overt stroke (n = 8) than for those without visible infarcts (n = 12) or control participants. Lesion volume was a robust predictor of IQ and other cognitive scores; total CC size did not typically add explanatory power for these measures. The size of the rostral body of the CC, however, independently predicted measures of distractibility, speeded production, and working memory. Posterior CC size was also decreased among many of the children with SCD, even in the absence of visible infarcts in this region. Brain morphology appears to provide additional information about SCD-related effects on the brain above and beyond visible infarcts. (JINS, 2006, 12, 24–33.)

Recent evidence suggests that changes in brain structure associated with alcohol abuse are compounded in individuals dually diagnosed with alcohol abuse and schizophrenia. To investigate the separate, and possibly interacting, effects of these diagnoses, an event-related brain potential (ERP) measure of auditory information processing (P50 sensory gating paradigm) and neuropsychological measures were administered to healthy control participants with either (1a) no history of alcohol abuse/dependence, or (1b) a remote history of alcohol abuse/dependence, and patients with schizophrenia with either (2a) no history of alcohol abuse/dependence, or (2b) a remote history of alcohol abuse/dependence. Schizophrenia was associated with impaired P50 sensory gating and poorer performance across neuropsychological scores compared to measurements in healthy control participants. Those with a positive alcohol history had impaired gating ratios in contrast to those with a negative alcohol history. There were additive effects of schizophrenia diagnosis and alcohol history for P50 sensory gating and for neuropsychological scores: attention, working memory, and behavioral inhibition. For executive attention and general memory there was an interaction, suggesting that the combination of schizophrenia and history of alcohol abuse results in greater impairment than that predicted by the presence of either diagnosis alone. (JINS, 2006, 12, 34–44.)

The relationship between dementia diagnosis and everyday action (e.g., meal preparation, grooming) is not well understood. This study examines differences between individuals diagnosed with vascular dementia (VaD; n = 25) versus Alzheimer's disease (AD; n = 23) on the Naturalistic Action Test (NAT; Schwartz et al., 2003), a performance-based measure that includes three tasks of increasing complexity. The percentage of task steps accomplished, number of errors, and performance times were recorded for each task. While the groups did not differ in dementia severity or overall impairment on the NAT, the VaD group committed more errors (3.3 vs. 1.6, p = 02). The VaD group also accomplished significantly fewer steps when salient distractor objects were present (74.0% vs. 91.3%, p < .01). Correlations between NAT variables and neuropsychological tests suggest the executive control deficits associated with VaD may contribute to specific action difficulties, such as distractor interference and inefficient, error-prone action on complex tasks. In AD, everyday action may be negatively influenced by episodic memory failures. Thus, dementia diagnosis has relevance to everyday function. (JINS, 2006, 12, 45–53.)

Very few empirically validated interventions for improving metacognitive skills (i.e., self-awareness and self-regulation) and functional outcomes have been reported. This single-case experimental study presents JM, a 36-year-old man with a very severe traumatic brain injury (TBI) who demonstrated long-term awareness deficits. Treatment at four years post-injury involved a metacognitive contextual intervention based on a conceptualization of neuro-cognitive, psychological, and socio-environmental factors contributing to his awareness deficits. The 16-week intervention targeted error awareness and self-correction in two real life settings: (a) cooking at home; and (b) volunteer work. Outcome measures included behavioral observation of error behavior and standardized awareness measures. Relative to baseline performance in the cooking setting, JM demonstrated a 44% reduction in error frequency and increased self-correction. Although no spontaneous generalization was evident in the volunteer work setting, specific training in this environment led to a 39% decrease in errors. JM later gained paid employment and received brief metacognitive training in his work environment. JM's global self-knowledge of deficits assessed by self-report was unchanged after the program. Overall, the study provides preliminary support for a metacognitive contextual approach to improve error awareness and functional outcome in real life settings. (JINS, 2006, 12, 54–63.)

Neuropsychological test results are affected by multiple factors, but usually age and education are the only variables by which norms are stratified. Some authors have questioned whether these variables alone are sufficient (e.g., Marcopulos et al., 1997; Manly et al., 2002), since such norms have lead to problems, such as poor specificity for African Americans on dementia screening devices (Fillenbaum et al., 1990). Recent research has shown that reading ability, a measure of educational quality, attenuated racial differences in test performance (Manly et al., 2002). We specifically examined whether reading ability would account for a greater amount of variance than education in executive function tests in a population traditionally subject to poor educational quality. Results determined that reading ability accounted for a significantly greater amount of variance than years of education for Letter-Number Sequencing, Similarities, COWA, Trail Making Test, and Coloured Progressive Matrices. Reading ability was found to significantly mediate the relationship between each of these tests and education. Animal naming appears to be least affected by educational quality or quantity. These findings hold implications for the interpretation of neuropsychological test results, especially in those exposed to substandard educational quality, and for the way that test norms are constructed. (JINS, 2006, 12, 64–71.)

The agreement between neuropsychologists identifying cognitive impairment (CI) in older adults was examined, as were factors influencing the classification process. Twenty four neuropsychologists in 18 study centers classified cases with or without CI after reviewing neuropsychological findings and other relevant information. All cases were participants in the third wave of the Canadian Study of Health and Aging, a study of CI in later life. For 117 randomly selected cases, a second neuropsychologist reviewed the same material and reclassified the cases. Cases given the same (concordant) or different (discordant) classifications were compared with respect to patient and rater characteristics. The inter-rater agreement was moderate (77.7% agreement, kappa = .49). On all measures of cognitive functioning, the concordant group without impairment obtained a higher mean score than the discordant group, and the discordant group obtained a higher mean score than the concordant group with impairment. For 5 out of 8 cognitive measures, the concordant group with impairment differed from the concordant group without impairment and the discordant group, but the latter two groups did not differ significantly. The findings are comparable to others in the field and highlight the need for neuropsychologists to further clarify procedures for identifying subtle, or mild, forms of cognitive impairment. (JINS, 2006, 12, 72–79.)

Previous research has indicated that performance on verbal fluency tests (VFTs) is influenced by language and/or culture. Consequently, normative VFT data for English-speaking people cannot be used for people for whom English is not their first language. The aim of the present study was to provide normative data for the Animal Naming, Profession Naming, and Letter M Naming (four-letter words beginning with the letter M) VFTs for Dutch-speaking populations, based on a large sample (N = 1856) of healthy men and women aged 24–81 years of different educational levels. The results showed that age affected the performance of all VFTs profoundly, but the age effect was not uniform: in the Profession and Letter M Naming VFTs, performance was stable in young adulthood but declined strongly after age 50. In contrast, in the Animal Naming VFT, performance appeared to decline linearly, starting early in life. Furthermore, males had higher scores than females on the Profession Naming VFT, and higher educated participants outperformed their lower educated counterparts on all three VFTs. Regression-based normative data were prepared for the 3 VFTs, and the advantages of using a regression-based normative approach instead of a traditional normative approach are discussed. (JINS, 2006, 12, 80–89.)

Drug addiction is associated with impaired judgment in unstructured situations in which success depends on self-regulation of behavior according to internal goals (adaptive decision-making). However most executive measures are aimed at assessing decision-making in structured scenarios, in which success is determined by external criteria inherent to the situation (veridical decision-making). The aim of this study was to examine the performance of Substance Abusers (SA, n = 97) and Healthy Comparison participants (HC, n = 81) in two behavioral tasks that mimic the uncertainty inherent in real-life decision-making: the Cognitive Bias Task (CB) and the Iowa Gambling Task (IGT) (administered only to SA). A related goal was to study the interdependence between performances on both tasks. We conducted univariate analyses of variance (ANOVAs) to contrast the decision-making performance of both groups; and used correlation analyses to study the relationship between both tasks. SA showed a marked context-independent decision-making strategy on the CB's adaptive condition, but no differences were found on the veridical conditions in a subsample of SA (n = 34) and HC (n = 22). A high percentage of SA (75%) also showed impaired performance on the IGT. Both tasks were only correlated when no impaired participants were selected. Results indicate that SA show abnormal decision-making performance in unstructured situations, but not in veridical situations. (JINS, 2006, 12, 90–99.)

Research findings have suggested that individuals with traumatic brain injury (TBI) show greater psychophysiological and subjective costs associated with performing vigilance tasks, but have not examined relationships with fatigue. The present study aimed to investigate vigilance and its relationship with subjective and objective fatigue measures. Forty-six TBI participants and 46 controls completed a 45-minute vigilance task. They also completed a subjective fatigue scale (the VAS-F) and a selective attention task before and after the vigilance task, and had their blood pressure (BP) monitored. TBI participants performed at a lower level on the vigilance task, but performed at a similar level across the duration of the task. Higher subjective fatigue ratings on the VAS-F were associated with more misses on the vigilance task for TBI participants. TBI participants showed greater increases in diastolic BP, and these were associated with greater increases in subjective fatigue ratings on the VAS-F. A subgroup of TBI participants showed a decline in performance on the vigilance task and also showed disproportionate increases in subjective fatigue. Findings provide support for the coping hypothesis, suggesting that TBI individuals expend greater psychophysiological costs in order to maintain stable performance over time, and that these costs are also associated with subjective increases in fatigue. (JINS, 2006, 12, 100–110.)

The present study investigated the utility of the International Classification of Diseases and Related Health Problems, 10th edition (ICD-10) diagnostic criteria for postconcussion syndrome (PCS) symptoms by comparing symptom endorsement rates in a group of patients with mild traumatic brain injury (MTBI) to those of a noninjured control group at one month and three months post-injury. The 110 MTBI patients and 118 control participants were group-matched on age, gender, and education level. Seven of the nine self-reported ICD-10 PCS symptoms differentiated the groups at one month post-injury and two symptoms differentiated the groups at three months post-injury: symptom endorsement rates were higher in the MTBI group at both time periods. Fatiguing quickly and dizziness/vertigo best differentiated the groups at both time periods, while depression and anxiety/tension failed to differentiate the groups at either time period. Collectively, the ICD-10 PCS symptoms accurately classified the MTBI patients at one month post-injury, with the optimal positive test threshold of endorsement of five symptoms coinciding with a sensitivity and specificity of 73% and 61%, respectively. The ICD-10 PCS symptoms were unable to accurately classify the MTBI patients at three months post-injury. (JINS, 2006, 12, 111–118.)

There is controversy regarding the nature and degree of intellectual and memory deficits in chronic Lyme disease. In this study, 81 participants with rigorously diagnosed chronic Lyme disease were administered the newest revisions of the Wechsler Adult Intelligence Scale (WAIS-III) and Wechsler Memory Scale (WMS-III), and compared to 39 nonpatients. On the WAIS-III, Lyme disease participants had poorer Full Scale and Performance IQ's. At the subtest level, differences were restricted to Information and the Processing Speed subtests. On the WMS-III, Lyme disease participants performed more poorly on Auditory Immediate, Immediate, Auditory Delayed, Auditory Recognition Delayed, and General Memory indices. Among WMS-III subtests, however, differences were restricted to Logical Memory (immediate and delayed) and Family Pictures (delayed only), a Visual Memory subtest. Discriminant analyses suggest deficits in chronic Lyme are best characterized as a combination of memory difficulty and diminished processing speed. Deficits were modest, between one-third and two-thirds of a standard deviation, consistent with earlier studies. Depression severity had a weak relationship to processing speed, but little other association to test performance. Deficits in chronic Lyme disease are consistent with a subtle neuropathological process affecting multiple performance tasks, although further work is needed to definitively rule out nonspecific illness effects. (JINS, 2006, 12, 119–129.)

Aphasia is extraordinarily common. Over one million people in the US currently suffer from aphasia. The personal and societal costs associated with aphasia are enormous. We live in a highly verbal world, and compromised language communication limits the aphasic's participation in society. Activities associated with a reasonable quality of life are highly constrained, and significant depression and other psychological costs are frequent. From a financial perspective, it is the aphasic's limited communicative capacity—not an associated motor disorder—that constrains employment and the ability to contribute productively to society. Thus, there are many reasons to pursue aphasia therapy. Yet effective aphasia therapies are few. Despite the frequency of aphasia and its enormous costs, resources devoted to the treatment of aphasia have been disappointingly modest.

Two patients (G01, J02) with chronic nonfluent aphasia and sentence production deficits received syntactic mapping treatment to improve sentence production. The patients had dramatically different outcomes in that improved syntax production generalized to nontreatment tasks for G01, but not for JO2. To learn how treatment influenced the neural substrates for syntax production, both patients underwent pre- and posttreatment functional magnetic resonance imaging (fMRI) of sentence generation. G01 showed more robust activity posttreatment than pretreatment in Broca's area; ventral temporal activity decreased slightly from pre- to posttreatment. Comparison of J02's pretreatment and posttreatment images revealed little change, although activity was more diffuse pre- than posttreatment. Findings suggest that for G01, rehabilitation led to engagement of an area (Broca's area) used minimally during the pretreatment scan, whereas for J02, rehabilitation may have led to more efficient use of areas already involved in sentence generation during the pretreatment scan. fMRI findings are discussed in the context of sentence-production outcome and generalization. (JINS, 2006, 12, 132–146.)

We explored the effect of education and occupational complexity on the rate of cognitive decline (as measured by the Mini-Mental State Examination) in 171 patients with a confirmed Alzheimer's disease (AD) diagnosis. Complexity was measured as substantive complexity of work and complexity of work with data, people, and things. Average lifetime occupational complexity was calculated based on years at each occupation. Participants were followed for an average of 2.5 years and 3.7 visits. In multivariate mixed-effects models, high education, high substantive complexity, and high complexity of work with data and people predicted faster rates of cognitive decline, controlling for age, gender, native language, dementia severity, and entry into the analyses at initial versus follow-up testing. These results provide support for the concept of cognitive reserve according to which greater reserve may postpone clinical onset of AD but also accelerate cognitive decline after the onset. (JINS, 2006, 12, 147–152.)

Cerebrovascular Disease, Cognitive Impairment and Dementia. John O'Brien, David Ames, Lars Gustafson, Marshal Folstein, and Edmond Chiu (Eds.). 2004. London: Martin Dunitz, 406 pp., $79.95 (HB).

Cerebrovascular Disease, Cognitive Impairment and Dementia is the second edition of Cerebrovascular Disease and Dementia (2000). The new edition is over 160 pages longer than the earlier version, with several new chapters devoted to the pathophysiology of cerebrovascular disease [including provocative chapters on neurotransmitter changes in vascular dementia (VaD), the contributions of homocysteine and low vitamin B to VaD, and a good overview of hereditary forms of VaD], vascular mild cognitive impairment, noncognitive symptoms, and an expanded discussion of prevention and treatment. It is written for both clinical and scientific audiences. As in the first edition, there is a laudable comparative emphasis, with epidemiologic studies of vascular dementia in Europe, North America, Japan, and China. Indeed, the editors hail from the U.K, Australia, Sweden, and the U.S, and this affords the volume a useful global perspective. With five editors and 22 additional contributors, however, this book suffers a bit from the “too many cooks” syndrome. There is a good bit of redundancy. After the fifth or sixth description of classification criteria for vascular dementia, the reader begins to feel on the receiving end of some repetitive rehearsal therapy for her own dementia.

Magnetic Resonance Imaging in Epilepsy: Neuroimaging Techniques (2nd Edition). Rubin I. Kuzniecky and Graeme D. Jackson (Eds.). 2005. New York: Elsevier. 431 pp., $149.95 (HB).

Readers of JINS are aware that the epilepsies are common, costly, and complex. Among the more common comorbidities are cognitive and neuropsychiatric disorders. The potential etiologies of these disorders include factors related to the cause, course, and treatment of the epilepsy, which may exert their effects, at least in part, through alterations in brain structure, metabolism, blood flow, and other dimensions of brain integrity. These effects can be captured and quantified by various neuroimaging techniques and greater familiarity with the diversity of neuroimaging approaches to epilepsy may open a variety of avenues of investigation.

Neuropsychology of PTSD: Biological, Cognitive, and Clinical Perspectives. Jennifer J. Vasterling and Chris R. Brewin (Eds.). 2005. New York: The Guilford Press, 337 pp., $48.00 (HB).

Philosophically, neuropsychologists believe the disorders they evaluate are of a natural kind: biologically real and existing independently of our means of classifying them, much like viruses or atomic structures exist separately from cultural outlook (McNally, 2004). We do not like to believe historical influences affect our evaluations, and nobody likes the idea that cognitive disorders can be created by merely marketing their existence. Social and cultural factors cannot be avoided when neuropsychologists move away from well-defined cerebral disorders to the study of subjectively defined disorders. Shorter (1994) elaborated the fluid presentation of hysteria over time, and ill-defined “railway spine” syndromes emerged when railroad accidents became compensable in 1800's Great Britain but not for orchard workers with similarly abrupt orthopedic strains. For a current controversy, consider how rising autism rates are believed to be biologically determined (e.g., mercury in vaccines) even though research underscores a proportional decline in mental retardation rates and autism rates still climbed long after mercury preservatives were eliminated in Denmark (Madsen et al., 2003). I refer to diagnostic “bracket creep” (e.g., “defining deviancy down” or “up” in the case of retardation), and “medicalization of misery,” variants of the idea that cultural pressures influence the vocabulary and scope of our inquiries. This can lead to increasing heterogeneity of our diagnostic categories, becoming a potentially insurmountable obstacle for those determined to discover a specific neurobiology for psychological suffering. Posttraumatic stress disorder (PTSD) is a myriad symptom constellation with widening boundaries under increasing neurocognitive scrutiny.