On the mild end of the acquired brain injury spectrum, the terms concussion and mild traumatic brain injury (mTBI) have been used interchangeably, where persistent post-concussive syndrome (PPCS) has been a label given when symptoms persist for more than three months post-concussion. Whereas a brief history of concussion research is overviewed, the focus of this review is on the current status of PPCS as a clinical entity from the perspective of recent advances in the biomechanical modeling of concussion in human and animal studies, particularly directed at a better understanding of the neuropathology associated with concussion. These studies implicate common regions of injury, including the upper brainstem, base of the frontal lobe, hypothalamic-pituitary axis, medial temporal lobe, fornix, and corpus callosum. Limitations of current neuropsychological techniques for the clinical assessment of memory and executive function are explored and recommendations for improved research designs offered, that may enhance the study of long-term neuropsychological sequelae of concussion. (JINS, 2008, 14, 1–22.)

Hemispatial neglect has been conceptualized as having dissociable and potentially clinically relevant subtypes. However, the question of whether patient performance on neglect subtype measures is consistent over time remains largely unanswered. We examined changes in performance over time on measures of motor, perceptual, and personal neglect in 21 patients with neglect from acute right hemisphere stroke. Patients were assessed on three occasions, separated by at least one week, using a lateralized target test, lateralized response test, and modified fluff test. Across three testing timepoints, 18 (85.7%) patients changed subtype performance patterns at least once. In 13 (61.9%) of these patients, inconsistency between timepoints was not adequately accounted for by recovery. On initial testing, seven, patients (33.3%) demonstrated more than one neglect subtype symptom; by the third testing timepoint none of the patients demonstrated multiple symptoms. In the setting of acute stroke, performance on three measures of neglect symptoms is inconsistent across time. However, the distribution of neglect subtype symptoms appears to become more discrete over time. These findings complicate our understanding of the pathophysiology and potential prognostic value of neglect subtypes, and suggest that treatment decisions based on subtype performance assessed at a single timepoint, may be of limited utility. (JINS, 2008, 14, 23–32.)

Unilateral neglect, a lack of awareness for one side of space, is a common and debilitating consequence of stroke. Previous work has identified a relationship between enduring left neglect and diminished general alertness and shown that increasing alertness can temporarily reduce the severity of the spatial bias. In that research, alertness was modulated by loud tones or with pharmacological stimulants. Here we examine whether cognitive, endogenously driven changes can produce similar short-term improvements. Time-pressure is associated with increased subjective arousal and increased activation in cortical regions associated with alertness. Here five patients completed a spatial cancellation task with and without instructions regarding a time limit. Significant reductions in neglect severity were observed when patients believed that they were acting under time-pressure, despite the conditions being equivalent in the actual (unlimited) time available. Functional imaging work has highlighted the secondary effects that damage to networks mediating alertness can have on structurally intact spatial systems. The results here suggest that activation of presumably spared function in these damaged networks can induce moment-by-moment changes in spatial function and, crucially, that this can be achieved using entirely endogenous means. (JINS, 2008, 14, 33–41.)

Atypical amygdala development may play a key role in the emergence of social disability and other symptoms of autism (Baron-Cohen et al., 2000; Schultz, 2005). The mechanisms by which this may occur have received little attention, however, and most support from behavioral and imaging studies has been concerned with socially relevant stimuli such as faces. Given the complexity of amygdala function and its known role in many other emotional tasks, we examined whether individuals with autism would demonstrate impaired performance on several tasks that have been shown to require activation of the amygdala but that do not have any explicit social meaning. Relative to a typical comparison group matched for age and IQ, our sample of 37 adolescents and adults with autism (mean age = 19.7 years) demonstrated equivalent facilitation for perception and learning of emotionally relevant stimuli. On each of four tasks, there were significant main effects of emotion condition on performance for both groups. Future research regarding atypical amygdala function and emotion processing in autism should consider whether the response to nonsocial emotion factors (including negative valence or high arousal) may be intact, despite difficulties in responding to socially relevant stimuli. (JINS, 2008, 14, 42–54.)

Major depression is associated with cognitive deficits including memory, executive functions, and affect perception, which have been linked to dysfunction of fronto-subcortical networks. However, little is known about social cognition on more complex socially relevant tasks, such as humor processing. In this investigation a computerized humor-processing task was administered to 27 patients with a diagnosis of major depression (Dep) and 27 healthy controls (HC). Theory of mind (mentalizing) and executive functions were also assessed. Both groups were similar in IQ, age, and gender. Depressed patients performed below the control group with respect to both affective and cognitive aspects of humor processing, and these were related to mentalizing and executive performance. Our findings suggest social cognition deficits in major depression. Ability to process humor and appreciate mentalistic perspectives may in turn influence social interactions and should be given consideration in therapeutic approaches to depression. (JINS, 2008, 14, 55–62.)

Individuals with acquired brain injuries (ABI) often experience depression following injury, with estimated rates between 20 and 40% within the first year and up to 50% thereafter (Fleminger et al., 2003). Previous studies with non–brain-injured individuals have identified that rumination is prevalent in both the development and maintenance of depression. The study aimed to explore how depressive rumination may contribute to overgeneral memory recall in ABI patients, by assessing the effects of manipulating ruminative self-focus on autobiographical memory performance across levels of brain injury. Fifty-eight ABI individuals with mild (28) to moderate/severe (30) cognitive impairments were assessed on measures of mood, rumination and autobiographical memory. They were then randomly assigned into matched groups for an intervention (a distraction) or a rumination task. Following intervention, they were re-assessed for autobiographical recall and rumination. Findings indicate that ruminative self-focus reduced specificity of autobiographical memory in individuals with ABI, suggesting that depressive rumination plays a role in the reduced access to autobiographical memories. Higher baseline levels of depression and rumination were also associated with less specificity in recall. These findings indicate the value of identifying and treating depression among this population. (JINS, 2008, 14, 63–70.)

Serial neuropsychological assessment is often conducted to monitor changes in the cognitive abilities of individuals over time. Because practice effects occur and the reliability of test scores is less than perfect, it is difficult to judge whether varying test results should be attributed to chance trends or to real changes in underlying cognitive abilities. In a large sample of adults (age range, 49–81 years), we evaluated the influence of age, gender, and education on test–retest changes in performance after 3 years on Rey's Verbal Learning Test (VLT), the Stroop Color-Word Test (SCWT), and the Letter Digit Substitution Test (LDST). A new statistical method was applied to assess the significance of changes in test performance (i.e., the regression-based change method). The results showed that test–retest changes differed as a function of age for the VLT Total recall 1–3, VLT Total recall 1–5, VLT Delayed recall, and LDST measures. An age × gender interaction was found for the SCWT Interference change score, suggesting that the age-related decline in executive functioning after 3 years was more pronounced for males than for females. A normative change table with appropriate corrections for the relevant independent variables was established. (JINS, 2008, 14, 71–80.)

We compared motor imagery performance of normally limbed individuals with that of individuals with one or both hands missing since birth (i.e., hand amelia). To this aim, 14 unilaterally and 2 bilaterally amelic participants performed a task requiring the classification of hands depicted in different degrees of rotation as either a left or a right hand. On the same task, 24 normally limbed participants recapitulated previously reported effects; that is, that the hand motor dominance and, more generally, a lifelong use of hands are important determinants of left–right decisions. Unilaterally amelic participants responded slower to hands corresponding to their absent, compared with their existing, hand. Moreover, left and right hand amelic participants showed prolonged reaction times to hands (whether left or right) depicted in unnatural orientations compared with natural orientations. Among the bilateral amelics, the individual with phantom sensations, but not the one without, showed similar differentiation. These findings demonstrate that the visual recognition of a hand never physically developed is prolonged, but still modulated by different rotation angles. They are further compatible with the view that phantom limbs in hand amelia may constrain motor imagery as much as do amputation phantoms. (JINS, 2008, 14, 81–89.)

Despite evidence for executive dysfunction in school-aged preterm children, less is known about the early development of these difficulties or their underlying neuropathology. This study used prospective longitudinal data from a regional cohort of 88 very preterm and 98 full-term comparison children to examine the executive functioning (EF) of preschool children born very preterm. The relationship between the severity of neonatal cerebral white matter (WM) abnormalities on magnetic resonance imaging (MRI) at term equivalent and children's EF at ages two and four years (corrected age) was examined. At age four, very preterm children with WM abnormalities performed less well than full-term children on the Detour Reaching Box, a measure of behavioral inhibition and cognitive flexibility, even after controlling for child IQ, SES, and medical background. Examination of patterns of EF performance between the ages of 2 and 4 years showed that the performance of all groups improved with age. However, very preterm children with mild and moderate-severe WM abnormalities were characterized by higher rates of consistent performance impairments. These findings support the presence of early and persistent executive difficulties in preschool children born very preterm, and highlight the importance of white matter pathology in the development of executive impairments. (JINS, 2008, 14, 90–101.)

The reason people read from top to bottom is unknown, but could be related to brain-mediated directional biases or environmental factors. To learn if there is a brain-mediated directional bias responsible for top–down reading direction, we evaluated the directional scanning in the vertical dimension by using directional letter and face cancellation tasks. Twenty participants were instructed to cancel either target letters or faces using either an up–down or down–up direction, with the stimuli located in left, right, and center hemispace. The results indicated significant differences in completion time between the search direction (up vs. down) and spatial position for the letter cancellation task, with a faster completion time for the bottom–up scan in right space and top–down in left space. Because the left hemisphere primarily attends to contralateral right hemispace our results suggest that, when attending to letter stimuli, the left hemisphere is biased to scan in a proximal to distal (upward) direction. Although the reasons why this is reversed in left hemispace and why we did not see directional biases in the face condition remains unclear, these results do suggest that the direction in which we learn to read is inconsistent with the brain's intrinsic directional bias. (JINS, 2008, 14, 102–109.)

There is evidence in the literature that cognitive functions in schizophrenia (SC) may be improved by atypical neuroleptics (NLPs) in contrast to typical medication, but there is still controversy regarding this apparent superiority of atypical drugs. In this study, we assessed the differential effects of risperidone and haloperidol on verbal memory, attention, and psychiatric symptoms in SC. The performance of 28 SC participants, randomly assigned to risperidone (2–6 mg/day) or haloperidol (2–40 mg/day), was compared with that of healthy controls. The California Verbal Learning Test (CVLT), the d2 Cancellation Test, and the Positive and Negative Symptoms Scale were administered at baseline and 3, 6, and 12 months. Relative to controls, all SC participants showed markedly impaired verbal memory and processing speed at each assessment period. There was no differential effect between the two NLPs on CVLT and d2 performance. However, risperidone was more effective than haloperidol in reducing psychiatric symptoms. Improvement in symptom severity was not associated with improvement in neurocognitive performance on these specific tests. Neither conventional nor atypical neuroleptic medications improved neurocognitive functioning over a 12-month follow-up, suggesting that psychopathological improvement under risperidone is independent of cognitive function. (JINS, 2008, 14, 110–118.)

Children with either fetal alcohol spectrum disorder (FASD) or attention-deficit/hyperactivity disorder (ADHD) display deficits in attention and executive function (EF) and differential diagnosis of these two clinical groups may be difficult, especially when information about prenatal alcohol exposure is unavailable. The current study compared EF performance of three groups: children with heavy prenatal alcohol exposure (ALC); nonexposed children with attention-deficit/hyperactivity disorder (ADHD); and typically developing controls (CON). Both clinical groups met diagnostic criteria for ADHD. The EF tasks used were the Wisconsin Card Sorting Test (WCST), the Controlled Oral Word Association Test (COWAT), and the Trail Making Test (TMT). Results indicated different patterns of deficit; both clinical groups displayed deficits on the WCST and a relative weakness on letter versus category fluency. Only the ALC group displayed overall deficits on letter fluency and a relative weakness on TMT-B versus TMT-A. In addition, WCST performance was significantly lower than expected based on IQ in the ADHD group and significantly higher than expected in the ALC group. These results, which indicate that, although EF deficits occurred in both clinical groups, the degree and pattern of deficit differed between the ALC and ADHD groups, may improve differential diagnosis. (JINS, 2008, 14, 119–129.)

As new and more effective treatments for Alzheimer's disease (AD) emerge, the development of efficient screening strategies in educationally and racially diverse primary care settings has increased in importance. A set of candidate screening tests and an independent diagnostic assessment were administered to a sample of 318 patients treated at a geriatric primary care center. Fifty-six subjects met criteria for dementia. Exploratory analysis led to the development of three two-stage screening strategies that differed in the composition of the first stage or Rapid Dementia Screen, which is applied to all patients over the age of 65. The second stage, applied to those patients who screen positively for dementia, is accomplished with the Free and Cued Selective Reminding Test to detect memory impairment. Using clinical diagnosis as a gold standard, the strategies had high sensitivity and specificity for identifying dementia and performed better for identifying AD than non-AD dementias. Sensitivity and specificity did not differ by race or education. The strategies provide an efficient approach to screening for early dementia. (JINS, 2008, 14, 130–142.)

Two hundred-thirteen children in grades 1 through 8 were asked to rapidly generate as many names of animals as they could in 60 seconds. These children were age appropriate for their grade level in school, did not receive any form of special education services, and as a group showed (estimated) average intellectual ability. They were primarily from minority (particularly Hispanic) backgrounds and came from families with low socioeconomic status. Normative data are presented. Hierarchical multiple regression analysis revealed that the age range/grade level score accounted for 21.5% of the variability in fluency scores and the Vocabulary level of the child accounted for an additional 5.7%. Level of performance on this animal fluency task was not lower than what has been reported in primarily white children from middle socioeconomic backgrounds. (JINS, 2008, 14, 143–147.)

The objective of this study is to obtain preliminary normative data on the performance the Pyramids and Palm Trees Test (PPT) for a Spanish-speaking population. The effects of age, gender, and educational level on the PPT test were also analyzed. A total of 234 healthy participants, with a broad range of age (18–80 years) and education (1–20 years) performed the three-picture version of the PPT. The mean performance was 51.1 out of 52 possible points (SD = 1.3). PPT performance did not vary with age or gender. However, subjects with less than 6 years of formal education scored significantly lower than those with more than 6 years of education though this effect was confounded with age because the group with lower education was also older. Given the ceiling effects of the PPT, further investigation is needed to determine if the visual PPT is sensitive to mild semantic memory impairment. (JINS, 2008, 14, 148–151.)

There are a number of devices now used in automobiles that allow subscribed companies to track the car and to aid the owner in the case of accidents, lockouts, being lost, etc. Even in the age of the cell-phone, having a human whom you can routinely contact and who is paid to help you when a problem occurs is reassuring. Given the forthcoming graying of the baby boomers with a significant proportion of us developing a dementia, along with the large number of people who suffer head injuries, strokes, and similar disorders, the market for a similar device, worn on the body—perhaps as a secured bracelet—appears obvious. Compensatory aids may have an important role to play in helping patients become functional—particularly when used as a reminder, to orient them to time and place, or to provide a human voice to give instructions when necessary. Since one operator potentially can handle many patients at the same time, it could be a cost-effective device to obtain. I say “may have an important role” because very few studies have used such a device, much less carefully evaluated its usefulness. In this issue, Fish, Manly, and Wilson (2008) describe a very nice application of a single-case design to evaluate the use of a compensatory device in a patient with a frontal lobe lesion associated with deficits in planning that were characterized as goal-neglect by the authors.

Evans et al. (1998) described compensatory strategy use in R.P., a patient with executive dysfunction following bilateral frontal lobe damage who had difficulty acting upon her intentions. A pager was used to remind R.P. of regularly scheduled activities, along with a checklist that aimed to moderate a perseverative routine. Although successful, 10 years after the original intervention, the strategies were no longer used, and considerable everyday problems were evident. In the current study, we conducted a follow-up assessment to examine potential reasons for this deterioration. No change in neuropsychological functioning was evident. Whereas the previous study introduced the two strategies together, and examined effects upon separate goals, in the current study we reintroduced the two strategies separately, and examined effects on three common goals. In addition to prompting specific activities, we aimed to support completion of more general goals (those that could be enacted within a wider window of time). The paging intervention had a dramatic effect on all three measured behaviors, at a much more consistent level than the checklist. We suggest that, in addition to direct reminders, the pager can cue a process of goal monitoring that bridges the gap between intention and action. (JINS, 2008, 14, 154–163.)

The extent to which letter-by-letter reading results from a specific orthographic deficit, as compared with a nonspecific disturbance in basic visuoperceptual mechanisms, is unclear. The current study directly compared processing of letters and digits in a letter-by-letter reader, G.M., using a rapid serial visual presentation (RSVP) task and a speeded matching task. Comparisons were made to a group of six brain-damaged individuals without reading deficits. In the RSVP task, G.M. had increased difficulty reporting the target identities when they were letters, as compared with digits. Although this general pattern was also evident in the control group, the magnitude of the letter–digit accuracy difference was greater in G.M. Similarly, in the matching task, G.M. was slower to match letters than digits, relative to the control group, although his response times to both item types were increased. These data suggest that letter-by-letter reading, at least in this case, results from a visuoperceptual encoding deficit that particularly affects letters, but also extends to processing of digits to a lesser extent. Results are consistent with the notion that a left occipitotemporal area is specialized for letter processing with greater bilaterality in the visual processing of digits. (JINS, 2008, 14, 164–173.)

Evolutionary Cognitive Neuroscience. 2007. Steven M. Platek, Julian P. Keenan, & Todd K. Shackelford (Eds.). Cambridge, MA: MIT Press, 616 pp., $65.00 (HB)

Clinical neuropsychologists are most interested in the ‘what’ of brain function. Neuropsychological assessment requires only a working knowledge of functional localization and the tests best suited to capture that specialization. The ‘why’ of cortical specialization is not necessary for good clinical work. The edited volume Evolutionary Cognitive Neuroscience is entirely devoted to the ‘how’ and ‘why’ of brain specialization based on the fact (not ‘theory’) of natural selection. Editors Steven Platek, Julian Keenan, and Todd Shackelford are well qualified to organize and write this book; they devoted their careers to understanding neuropsychological functions as evolved mechanisms designed to solve recurrent survival and reproduction problems of our evolutionary past. In this view, our brains are Stone Age computers.

The Behavioral and Cognitive Neurology of Stroke. 2007. Olivier Godefroy and Julien Bogousslavsky (Eds.). Cambridge, UK: Cambridge University Press, 664 pp., $160.00 (HB)

The Behavioral and Cognitive Neurology of Stroke is a very handy reference book for the bedside or brief office examination of the stroke patient. The initial chapter highlights the need for serial mental status exams during the critical initial post stroke period. The book is then organized by functional sections, each containing several chapters. The sections are organized by neuropsychological processes in the usual “walk around the brain” format. Thus, the reader is offered sections on motor and gestural disorders, aphasia and arthric disorders, hemineglect and right hemisphere syndromes, agnosia and Balint's syndrome, and executive and memory disorders. Of great significance is the inclusion of a section on behavioral and mood disorders, which reviews the clinical domains where the disciplines of psychiatry and neurology overlap. The final section, dementia and anatomical left/right syndromes, extends and integrates the previous sections.