Neurocognitive dysfunction after coronary artery bypass surgery: a systematic review

OBJECTIVE

Substantial, albeit scattered, evidence suggests that coronary artery bypass grafting may impair cognitive function. As methods and definitions differ greatly across studies, the reported incidence of cognitive decline after coronary bypass surgery varies widely as well. The aim of the present study was to systematically review those studies on cognitive decline that are relatively comparable and meet with certain quality criteria.

METHODS

Four electronic databases and the references of several abstract books and earlier reviews were used to identify relevant literature. Stringent criteria, based in part on the 1994 consensus meeting on assessment of neurobehavioral outcomes after cardiac surgery, were used to assess the studies that were found. In total, 256 different titles were found, of which 23 met with the formulated selection criteria.

RESULTS

Twelve cohort studies and eleven intervention studies were evaluated. A pooled analysis of six highly comparable studies yielded a proportion of 22.5% (95% confidence interval, 18.7%-26.4%) of patients with a cognitive deficit (a decrease of at least 1 standard deviation in at least two of nine or ten tests) 2 months after the operation.

CONCLUSIONS

Neurocognitive dysfunction is a frequently occurring complication of coronary artery bypass grafting. The etiologic contribution of cardiopulmonary bypass to this complication will remain unclear until a randomized trial that directly compares off-pump and on-pump bypass surgery is carried out.

Sex differences in identifying the facial affect of normal and mirror-reversed faces

The influences of sex and lateralized visual hemispace bias in the judgment of the emotional valence of faces during a free viewing condition are evaluated. 73 subjects (aged 18 to 52 yr.) viewed videotaped facial expressions of emotion in normal and mirror-reversed orientation and classified each face as a positive, negative, or neutral expression. There was a significant interaction between the sex of the rater and the orientation of the face that influenced the proportion of correct classifications. Male and female perceivers did not differ in the accuracy of their affect judgments for faces viewed in normal orientation, whereas reversal of the orientation of the faces resulted in a significant enhancement of accuracy judgments for the males but not the females. The results suggest greater cerebral lateralization of perceptual processes in males.

Factor structure of nonverbal cognition

In order to define the factor structure of nonverbal cognitive processes, 156 twenty to sixty year-old participants were selected in Medellin (Colombia). A neuropsychological test battery for assessing different nonverbal cognitive domains (attention, memory, visuoperceptual and visuoconstructive abilities. executive functions, praxis abilities, and written calculation abilities) was administered. Initially, independent factor analyses were carried out for each domain. Three attention factors (Sustained Attention, Divided Attention, and Processing Speed, 73.1% of the variance); two memory factors (Categorical and Non-Categorical Memory, 59.7% of the variance): two visuoperceptual and visuoconstructive factors (Sequential and Simultaneous, 54.0% of the variance); and two executive function factors (Categorization and Trial Error, 82.0% of the variance) were found. Further, several sequential factor analyses using Varimax orthogonal rotations for noncorrelated variables were performed. The 32 test variables were included, but progressively some variables were removed. This procedure finally selected 13 variables corresponding to five factors accounting for 72.6% of variance. Factor I was an Executive Function factor (30% of variance). Factor 2 corresponded to a Sequential Constructional factor (14.7%). Factor 3 represented a Processing Speed factor and accounted for 10.6% of the variance. Factor 4 was Visuoperceptual factor (9.5% of the variance). Finally, Factor 5 (7.8% of the variance) was a Nonverbal Memory factor. It was concluded that several, different cognitive dimensions are included in nonverbal cognition.

The postconcussion syndrome after mild head trauma: is brain damage overdiagnosed? Part 1

Many investigators attribute the postconcussion syndrome following mild closed head injury to permanent brain damage. The evidence supporting this conclusion is reviewed, including the force necessary to cause permanent brain damage; the basis for determining whether the patient was exposed to sufficient force in the accident to permanently damage the brain; the basis for determining whether the patient actually has permanent brain damage (not just brain dysfunction) traceable to the accident; and whether the location and severity of brain damage is sufficient to account for the postconcussion syndrome.

CONCLUSION

the evidence for permanent traumatic brain damage as the cause of the postconcussion syndrome following mild closed head injury is weak.

Neurodevelopmental dysfunction and specific learning disabilities in school-aged twins

The frequency of the developmental dysfunction and specific learning disabilities were assessed in the retrospective study in the group of 56 school-aged twins. The relationships between genetic, perinatal and social factors and learning disability were also determined. It was found that 12.5% of twins had learning disabilities. The most common neurodevelopmental dysfunction were language disorders, poor graphomotor fluency and poor fine motor dexterity. It was also found that educational difficulty were associated with prematurity, low Apgar scores, neonatal complications and familial predisposition.

TMT, a predator odor, elevates mesoprefrontal dopamine metabolic activity and disrupts short-term working memory in the rat

Working memory has been proposed to require the proper functioning of the medial prefrontal cortex and its dopaminergic innervation. The dopaminergic input to the medial prefrontal cortex has been demonstrated to be sensitive to physical and psychological stress. In this report, we demonstrate that a brief exposure to 2, 5-dihydro-2,4,5-trimethylthiazoline (TMT), an odor derived from a predator of the rat, the fox, resulted in elevated dopamine metabolism in the medial prefrontal cortex and elevated serum corticosterone. We tested the effects of this olfactory stress on working memory using a spontaneous, delayed, non-matching-to-sample task using object recognition methods. Rats were exposed to one set of objects and, after a delay of 1, 15 or 60 min, later demonstrated a robust working memory of the familiar object compared to a novel object. When rats were exposed to TMT during the 15-min delay, working memory was disrupted without altering exploratory behavior. We conclude from these studies that (1) TMT selectively activates mesoprefrontal dopamine neurons, (2) TMT exposure can disrupt working memory and (3) this disruption in working memory is not due to an overall suppression of exploratory behavior but may involve altered mesoprefrontal dopaminergic activity.

The unity and diversity of executive functions and their contributions to complex "Frontal Lobe" tasks: a latent variable analysis

This individual differences study examined the separability of three often postulated executive functions-mental set shifting ("Shifting"), information updating and monitoring ("Updating"), and inhibition of prepotent responses ("Inhibition")-and their roles in complex "frontal lobe" or "executive" tasks. One hundred thirty-seven college students performed a set of relatively simple experimental tasks that are considered to predominantly tap each target executive function as well as a set of frequently used executive tasks: the Wisconsin Card Sorting Test (WCST), Tower of Hanoi (TOH), random number generation (RNG), operation span, and dual tasking. Confirmatory factor analysis indicated that the three target executive functions are moderately correlated with one another, but are clearly separable. Moreover, structural equation modeling suggested that the three functions contribute differentially to performance on complex executive tasks. Specifically, WCST performance was related most strongly to Shifting, TOH to Inhibition, RNG to Inhibition and Updating, and operation span to Updating. Dual task performance was not related to any of the three target functions. These results suggest that it is important to recognize both the unity and diversity of executive functions and that latent variable analysis is a useful approach to studying the organization and roles of executive functions.

Neuropsychologische Diagnostik im Kindes- und Jugendalter

Zusammenfassung: Bei einer Vielzahl von Fragestellungen und Störungsbildern sollte neuropsychologische Diagnostik einen festen Stellenwert haben, sowohl in der initialen wie auch in der Verlaufsbeurteilung. Mit Blick auf die Anwendung in der Kinder- und Jugendpsychiatrie ist zunächst eine beschreibende Definition dieses Bereichs psychologischer Diagnostik zu versuchen. Dabei bestehen methodisch grundlegend unterschiedliche Zugangswege, die in ihren Auswirkungen auf Psychometrie wie Interpretation zu erörtern sind. Unabhängig davon, dass die gegenwärtige Verfügbarkeit standardisierter neuropsychologischer Diagnostik nur in einigen Bereichen befriedigen kann, wird eine Darstellung der in klinischer Praxis und/oder Forschung anwendbaren Verfahren versucht. Neben einzelnen Testbatterien werden Einzeltestverfahren für die Bereiche visuelle und auditive Gedächtnisfunktionen, Aufmerksamkeitsfunktionen, sprachassoziierte Funktionen und Exekutivfunktionen besprochen. Der aktuelle Stand neuropsychologischer Diagnostik führt zu wesentlichen Aufgaben ihrer Weiterentwicklung. Dies gilt sowohl für kurzfristig erreichbare Ziele wie Adaptation oder Normierung verfügbarer Instrumente als auch für längerfristige Forschungsaufgaben.

Sulcal/gyral pattern morphology of the perisylvian language region in developmental dyslexia

Two systems for classification of morphology of the perisylvian cortical area have been suggested, that of Steinmetz et al. (1990) and that of Witelson and Kigar (1992). This study examines whether the variations in placement of these convolutions in the language cortex are related to diagnosis of dyslexia in a clinic-referred sample of 55 children ages 8 to 12 years. Additionally, the systems are compared to determine their relationship to neurolinguistic performance. In this study, the Steinmetz et al. (1990) system captured morphological distinctions which were relevant to performance on neurolinguistic measures, while Witelson and Kigar's (1992) system did not. Under neither system was morphology associated with diagnosis of dyslexia.

Cognitive-behavioural assessment and treatment of maladaptive help-seeking behaviour in a patient with schizophrenia

OBJECTIVE

Maladaptive help-seeking behaviour in psychiatric patients is a significant problem for public mental health services, yet it is not addressed in the mainstream literature. We present a report on the successful treatment of a person with schizophrenia who displayed this common dilemma for patients and clinicians.

CLINICAL PICTURE

A 31-year-old man with borderline intellectual functioning had a 10-year history of schizophrenia marked by negative features. He frequently presented in crisis to public mental health services, the local hospital, and his general practitioner; this resulted in excessive use of services, including admissions.

TREATMENT

The patient was reassessed from a cognitive-behavioural perspective rather than a syndromal perspective. Specific behaviours were modified, cognitions were identified, challenged and restructured, and other service providers were provided with an alternative to admission or acute community care.

OUTCOME

At 24 months the maladaptive behaviour remains in remission.

CONCLUSIONS

Behavioural problems in persons with chronic schizophrenia may be effectively treated by reconceptualising the behaviour as distinct from the major diagnosis.

A clinical profile to predict decision making, risk behaviors, clinical status, and health-related quality of life for cancer-surviving adolescents. Part 1

The purpose of this two-part series is to describe a multifactorial model of clinical factors predicting decision-making quality, risk behaviors, clinical status, and health-related quality of life for cancer-surviving adolescents. This model was developed as a clinical profile to help health professionals in better identifying cancer-surviving adolescents at highest risk for substance use. Findings in the literature and results from the program of research by the author are presented to support the conceptualization of the model. In part 1, support for the antecedent predictors, both primary and secondary factors, is presented. Part 2 addresses decision making as a mediator, risk motivation as a moderator, and the expected outcomes related to risk behaviors, clinical status, and quality of life. In addition to describing the first part of the clinical profile in part 1, the background, theoretical basis of the model, and definitions of the model constructs also are provided.

Age and neuropsychologic function in schizophrenia: a decline in executive abilities beyond that observed in healthy volunteers

BACKGROUND

Kraepelin originally conceptualized schizophrenia as a degenerative brain disorder. It remains unclear whether the illness is characterized by a static encephalopathy or a deterioration of brain function, or periods of each condition. Assessments of cognitive function, as measured by neuropsychologic assessment, can provide additional insight into this question. Few studies of patients with schizophrenia have investigated the effect of aging on executive functions, in an extensive neuropsychologic battery across a wide age range, compared to healthy volunteers.

METHODS

We examined the interaction of aging and neuropsychologic function in schizophrenia through a cross-sectional study in patients (n = 87) and healthy control subjects (n = 94). Subjects were divided into three age groups (20-35, 36-49, and 50-75), and performance on an extensive neuropsychologic battery was evaluated.

RESULTS

Compared to control subjects, patients with schizophrenia demonstrated similar age-related declines across most neuropsychologic functions, with the exception of abstraction ability, in which significant evidence of a more accelerated decline was observed.

CONCLUSIONS

These results are consistent with previous reports indicating similar age effects on most aspects of cognition in patients with schizophrenia and healthy adults, but they support the hypothesis that a degenerative process may result in a more accelerated decline of some executive functions in older age in schizophrenia.

Hand response differences in a self-face identification task

Evidence has indicated that the right frontal cortex is preferentially involved in self-face recognition. To test this further, we employed a face identification task and examined hand response differences (N=10). Pictures of famous faces were combined with pictures of the participants' faces (self) and their co-workers' faces (familiar). These images were presented as a 'movie' in which one face transformed into another. Under the first instruction set, the movies began with either the participant's face or a co-worker's face, and the sequences gradually morphed into a famous face. When told to stop the movie when the face in the sequence became famous, a significantly later 'frame' was identified when the movies were composed of self-faces and the participants responded with their left hand. When the movies started with the famous faces and participants had to stop the movie when it became their own or their familiar co-worker's image (Instruction set 2), a significantly earlier frame was identified in the 'Self: Left hand' condition. The data suggest that participants are inclined to identify images as their own when the right hemisphere is preferentially accessed.

Digitizing the moving face during dynamic displays of emotion

Humans typically decode facial signals during dynamic interactions in which the face moves. In this study, we digitized real time video signals in order to examine movement asymmetries across the face during emotional and nonemotional expressions. Forty dextral males were tested. For each expression, a 400 ms video segment was analyzed for changes in signal value (pixel intensity) over consecutive frames. The upper and lower face regions were examined separately due to differences in the cortical enervation of facial muscles in the upper (bilateral) vs lower face (contralateral). Results revealed distinctly different movement asymmetries over the lower and upper hemiface. In the upper face, more movement occurred over the right side for most facial expressions, regardless of emotionality. The latter finding questions the assumption that muscles of the upper face are symmetrical and/or bilaterally enervated in a symmetrical manner. In the lower face, negative expressions linked to fight-flight emotions (i.e. fear, anger) were associated with greater left sided movement, whereas happiness tended to be associated with more right sided movement. No consistent pattern of movement asymmetry occurred for nonemotional expressions. Although the valence-related movement asymmetries in the lower face are consistent with neuropsychological models of emotional expressivity, it remains unclear whether they reflect activation or inhibitory hemispheric mechanisms. Taken together, these data suggest that multiple factors may contribute to expressive movement asymmetries of the face.

Regional cerebral blood flow during exposure to food in obese binge eating women

Cerebral responses elicited by the sight of food were evaluated in eight obese binge eating, 11 obese and 12 normal-weight non-binge eating women. Regional cerebral blood flow (rCBF) was mapped while the subjects were looking at a picture of a landscape (control) or at a portion of food (food exposure), and was measured by [99mTc]ethyl-cysteine-dimer and single photon emission computed tomography. Exposure to food was associated with different changes in the cerebral blood flow (normalized to mean cerebellar counts) of the right and left hemispheres in the obese binge eating than in the obese or normal-weight non-binge eating women. As compared with the non-binge eating groups, the obese binge eating women had, due to food exposure, a greater increase in the cerebral blood flow in the left than right hemisphere, especially in the frontal and pre-frontal regions. In addition, strong linear correlations were observed in this group between the rCBF of the left frontal and pre-frontal regions and the increase in the feeling of hunger during the exposure to food. Left hemisphere and its frontal and pre-frontal regions could thus play a role in binge eating behavior in humans.

Chronic effects of dopaminergic replacement on cognitive function in Parkinson's disease: a two-year follow-up study of previously untreated patients

BACKGROUND

The cognitive effects of dopaminergic treatment in Parkinson's disease (PD) are still controversial.

OBJECTIVE

To evaluate, in previously untreated patients with PD, whether chronic dopaminergic stimulation produces significant cognitive changes; whether they are sustained beyond the period of a few months; and whether the cognitive status of two motor-comparable groups is differently affected by levodopa and pergolide.

DESIGN AND SUBJECTS

Parallel, randomized open study with blind neuropsychologic evaluation of 20 consecutive de novo patients with PD before and 3, 6, 12, 18, and 24 months after monotherapy with levodopa (n = 10) or pergolide (n = 10; 6-month monotherapy; pergolide + levodopa thereafter).

RESULTS

Both treatments were associated with a significant improvement in motor scores and in tests assessing learning and long-term verbal and visual memory, visuospatial abilities, and various frontal tasks. While improvement in motor scores persisted, improvement in activities of daily living and in semantic fluency, Luria's rhythm and motor and long-term memory tests was not sustained at the 24-month examination. Further, performance on attentional, short-term memory, and the Stroop tests did not change over the course of the study.

CONCLUSIONS

Both treatments were associated with incomplete but long-lasting (18 mos) improvement in many cognitive tasks which declined thereafter, suggesting that dopaminergic replacement is not enough to compensate for all cognitive deficits of PD.

Intraoperative hippocampal electrocorticography to predict the extent of hippocampal resection in temporal lobe epilepsy surgery

OBJECT

Among the variety of surgical procedures that are performed for the treatment of medically refractory mesial temporal lobe epilepsy (TLE), no consensus exists as to how much of the hippocampus should be removed. Whether all patients require a maximal hippocampal resection has not yet been determined.

METHODS

At the University of Washington, all TLE operations are performed in a tailored fashion, guided by electrocorticography (ECoG). The amount of hippocampal resection is determined intraoperatively by the extent of interictal epileptiform abnormalities on ECoG recorded from that structure, resulting in a hippocampal resection that is individualized for each patient. Using this approach, the authors prospectively observed 140 consecutive patients who underwent surgery for mesial TLE with pathological diagnoses of either mesial temporal sclerosis with neuronal loss (MTS group) or mild gliosis without neuronal loss (non-MTS group) to determine whether the extent of hippocampal resection correlates with outcome when a tailored approach is used. Additionally, the authors analyzed whether the presence of residual interictal epileptiform activity on ECoG following mesial temporal resection predicts poorer seizure control. With at least 18 months of clinical follow up, 67% of the 140 patients were seizure free or had only a single postoperative seizure. There was no correlation between the size of the hippocampal resection and seizure control in the group as a whole or when stratified by pathological subtype. Using an intraoperatively tailored strategy, individuals with a larger hippocampal resection (> 2.5 cm) were not more likely to have seizure-free outcomes than patients with smaller resections (p = 0.9). Additionally, both MTS and non-MTS patients, in whom postoperative ECoG detected residual epileptiform hippocampal (but not cortical or parahippocampal) interictal activity following surgical resection, had significantly worse seizure outcomes (p = 0.01 in the MTS group; p = 0.002 in the non-MTS group).

CONCLUSIONS

Intraoperative hippocampal ECoG can predict how much hippocampus should be removed to maximize seizure-free outcome, allowing for sparing of possibly functionally important hippocampus.

Self-face identification is increased with left hand responses

Evidence suggests that autobiographical memory, self-related semantic category judgements, and self-identification tasks may be lateralised, with preferential activity in the right anterior temporal and prefrontal cortex. To test this hypothesis, participants (N=10) were presented with morphed images of themselves (self) combined with a famous face. A further set of images was generated in which the face of one of the participant's co-workers (familiar) was combined with a famous face. When compared to morphed images composed of a familiar face, the participants identified images less often as being famous if the images were composed of self, but only when responding with their left hands. This greater "self-effect" found in left-hand responses may imply that when the right hemisphere is preferentially active, participants have a tendency to refer images to self. These data provide further support for a preferential role of the right hemisphere in processing self-related material.

Precursors of lethal violence: a death row sample

A qualitative methodology based on the standards of criminal defense investigation was used to analyze the social and family histories of 16 men sentenced to death in California. Using a multisource cross-validation methodology, we assessed patterns of impairment, injury and deficit at each of four ecological levels: family, individual, community and social institutions. Investigation documented consistent and pervasive patterns of serious impairment, injury and deficit across the cases and levels. The men share numerous risk factors and few resiliency factors associated with violence. We found family violence in all 16 cases, including severe physical and/or sexual abuse in 14 cases; individual impairments in 16, including 14 with post-traumatic stress disorder, 13 with severe depression and 12 with histories of traumatic brain injury; community isolation and violence in 12; and institutional failure in 15, including 13 cases of severe physical and/or sexual abuse while in foster care or under state youth authority jurisdiction. Appropriate interventions might have made a difference in reducing lethal violence and its precursor conditions.

The efficacy of Le Bon Départ and Sensory Integration treatment for children with developmental coordination disorder: a randomized study with six single cases

OBJECTIVE

Evaluation of the efficacy of Le Bon Départ (LBD) treatment and Sensory Integration (SI) treatment on motor performance of children with developmental coordination disorder.

DESIGN

A single subject design with multiple baseline and alternating treatments. Order of treatment and length of phase were randomized. Measurements were blinded.

SETTING

Department of Occupational Therapy at the Academic Hospital Vrije Universiteit Amsterdam, The Netherlands.

SUBJECTS

Five boys and one girl with developmental coordination disorder (age: 6.0-8.1 years).

INTERVENTIONS

Baseline condition, Le Bon Départ treatment and Sensory Integration treatment.

MAIN OUTCOME MEASURES

The Movement ABC, Praxis Tests, a rhythm test and visual analogue scales. With the exception of the Praxis Tests, lower scores indicate better performance.

RESULTS

During both treatments, the performance on the Movement ABC (x = 7.21) and the scores on the visual analogue scales (x = 46.64) were significantly better than in the baseline (Movement ABC(baseline): x = 17.38; visual analogue scales(baseline): x = 68.18). After treatment 2, performance on the Praxis Tests and scores on the visual analogue scales were significantly better than after treatment 1 (Praxis Tests: 113.54 versus 104.68; visual analogue scales: 34.74 versus 58.54). All six children performed better on the Movement ABC during treatment as compared to the baseline. Le Bon Départ led to significant improvement on all dependent variables, Sensory Integration on the visual analogue scales only. The improvements after Le Bon Départ were larger than the improvements after Sensory Integration treatment. On the rhythm test this difference was significant: LBD led to an improvement of 43.01 points, while the improvement after SI was 17.59 points (p < 0.05).

CONCLUSION

Motor performance of children with developmental coordination disorder improved significantly on all dependent variables after the combination of treatments. Le Bon Départ led to more improvement than Sensory Integration. LBD appears to be a valuable treatment method for children with developmental coordination disorder.

Psychiatric treatment outcome following traumatic brain injury

The relationship between self-reported history of traumatic brain injury (TBI) and psychiatric treatment outcome was investigated. TBI was hypothesized to be frequent, associated with cognitive deficits on neuropsychological testing, and less amenable to standard psychiatric treatment. Subjects were 42 psychiatric patients with a self-reported history of TBI and 25 psychiatric patients with no TBI history. Subjects received approximately 2 weeks of inpatient psychiatric treatment. Subjects received neuropsychological testing and completed the Brief Symptom Inventory weekly. TBI was frequent (66% of subjects); multiple injuries were common. Neuropsychological performance was generally average in both groups with few group differences. Subjects, on average, reported significantly decreased psychiatric symptoms on discharge. However, the TBI group appeared to improve less than the control group; group status was a significant predictor of treatment outcome. Implications of results for assessment and treatment of psychiatric disorders in patients with a history of TBI are discussed.

Executive control functions in degenerative dementias: a comparative review

This paper reviews the literature concerning executive control impairments in degenerative dementias. The construct of executive control functioning is examined, as is the neuroanatomy of frontal-subcortical networks, believed to underlie executive function (EF) impairments. The pattern of EF impairments in Alzheimer's disease (AD) which affects temporal and parietal brain regions most severely is contrasted with observed executive dysfunctions in patients with dementias involving degeneration of primarily frontal and frontal-subcortical brain areas. EF impairments are present in each of these types of dementing illnesses. Although EF impairments are present in AD, they are less prominent than the memory disorder in the neuropsychological profile of the disease and tend to become more pronounced later in the course of the illness. In contrast, patients with frontal or frontal-subcortical dementia may demonstrate executive dysfunction, which occurs earlier in the disease progression and may be initially more severe.

Does the letter number sequencing task measure anything more than digit span?

A total of 102 undergraduate students performed the Letter Number Sequencing (LNS) task in addition to a series of other measures of reading, working memory, motor execution, visuo-spatial memory, and executive functions. Performance on the LNS was uniquely contributed to by reading level, digit span forward and backward, arithmetic, visual spatial learning, and by performance on the Symbol Search subtest of the WAIS-III. The results indicate that while much of the variance on the LNS task is explained by performance on the traditional measures of digit span, additional unique contributions to prediction of LNS performance are provided by measures of processing speed and visual spatial working memory.

Visual attention impairments in Alzheimer's disease

BACKGROUND

Impaired attention can hinder information processing at multiple levels and may explain aspects of functional decline in aging and dementia. Impairments of attention in early AD may contribute to performance reductions in other cognitive domains, including memory and executive functions.

METHOD

- The authors analyzed the scores on a battery of tests of attention and cognitive abilities in 64 older individuals: 42 with mild AD and 22 control subjects without dementia. The authors tested the hypotheses that patients with AD would have impairments of visual attention, and that these impairments would correlate with dysfunction in other key cognitive domains.

RESULTS

Patients with AD performed significantly worse than control subjects on measures of sustained attention, divided attention, selective attention, and visual processing speed. The differences were not due to differences in age, education, or basic visual function. Strong relationships were identified between reduced attention skills and overall cognitive impairment.

CONCLUSIONS

Deterioration of attention abilities occurs in early stages of AD, and likely contributes to functional decline in these patients. More routine assessment of visual attention deficits could give a more accurate measure of functionally useful perception in patients with AD who show normal visual acuity and visual fields, perhaps providing useful clues to diagnosis and staging.

Verbal fluency and executive dysfunction in amyotrophic lateral sclerosis (ALS)

Neuropsychological investigations of amyotrophic lateral sclerosis (ALS) patients have revealed variable results on specific tests, despite a similar overall cognitive profile of predominantly executive dysfunction with some evidence of memory impairment. The most striking and consistent deficit is found using tests of verbal fluency. The current investigation explored why verbal fluency is particularly sensitive to the impairment in ALS, by investigating some of the underlying cognitive processes: (i) intrinsic response generation; (ii) phonological loop functions; and (iii) simple word retrieval. Twenty-two ALS patients and 25 healthy controls were investigated. The battery included: (i) written and spoken letter-based fluency, category fluency, design fluency; (ii) the Phonological Similarities effect and Word Length Effect; and (iii) computerised sentence completion and confrontational naming. The tests were designed to control for motor speed and to accommodate for the range of disabilities that are present in ALS patients. Significant impairments were found on some tests of intrinsic response generation, namely the Written Verbal Fluency Test, Category Fluency Test (generation of animal names) and Design Fluency Test. Phonological loop functions appeared to be intact with evidence of both the Phonological Similarities and Word Length Effects, but the ALS patients displayed significantly reduced working memory capacity. No deficits were found on tests of simple word retrieval. The findings indicate that verbal fluency impairments in ALS patients result from a higher order dysfunction, implicating deficits in the supervisory attentional system or central executive component of working memory, and are not caused or exaggerated by an impairment in phonological loop functions or in primary linguistic abilities. The study also demonstrates the importance of controlling for differences in motor speed, which may have served to exaggerate the presence of cognitive deficits in ALS patients reported by some other studies.

Age differences and changes in midline-crossing inhibition in the lower extremities

BACKGROUND

The effects of crossing the body midline on the lower extremities of individuals 65 years of age and older was investigated.

METHODS

The subjects were 10 individuals 65-79 years of age, 10 individuals 80 years and older, and 10 individuals 20-35 years. The total testing phase consisted of 2 sets of 30 trials per leg on 2 days. The subjects performed trials that involved movements ipsilaterally, contralaterally, and directly in front of the anterior superior iliac crest of the leg being tested. Reaction time and movement time scores were recorded.

RESULTS

Individuals 65 years of age and older were found to exhibit slower reaction times to movements in a contralateral direction when compared with movements made in the ipsilateral direction whereas individuals 80 years of age and older were also found to exhibit slower reaction times to movements in a contralateral direction when compared with movements made in the midline and ipsilateral direction.

CONCLUSIONS

These findings indicate that the effects of midline-crossing inhibition on the lower extremities reemerge in individuals 65 years and older, whereas in early development this effect disappears by 8 or 9 years of age.

Cholinergic modulation of inhibitory avoidance impairment induced by paradoxical sleep deprivation

1. Male Wistar rats were submitted to paradoxical sleep deprivation for 96 hr by a modified multiple platform technique. 2. Training of step-through inhibitory avoidance was performed immediately after the last day of paradoxical sleep deprivation. Twenty-four hr after training the animals were submitted to the retention test. 3. In Experiment 1, pilocarpine (4 mg/kg, i.p.) or atropine (4 mg/kg, i.p.) were administered daily during the paradoxical sleep deprivation period. Pilocarpine, but not atropine, reversed the impairment induced by PS deprivation. 4. In Experiment 2, pilocarpine (4, 8 and 12 mg/kg, i.p.) was injected 1 hr before training in order to verify if the reversal of memory impairment was an effect secondary to residual enhanced blood levels of pilocarpine during training. Acute treatment with pilocarpine, in any dose, did not reverse the impairment produced by paradoxical sleep deprivation 5. Activation of the cholinergic system during the period of deprivation is able to prevent memory deficits induced by paradoxical sleep deprivation.

Wisconsin Card Sorting in adolescents: analysis of performance, response times and heart rate

Forty-nine adolescents performed the Wisconsin Card Sorting Test (WCST). A main PCA component of WCST performance was identified as 'efficiency of reasoning'. This factor was related to feedback processing. From the WCST, a perseveration score can be derived. Perseveration is the continued application of a rule, after it has been disconfirmed. We compared more and less perseverating subjects in relation to stimulus-response (SR) time, feedback inspection time and cardiac acceleration and deceleration. Less perseverating subjects responded faster, and had longer and more adaptive inspection times of error feedback. We examined the switch from rule application to rule search, and the difference between correct and error responses. A transient cardiac deceleration at the initiation of rule search was interpreted as a change in supervisory attention. An error-related deceleration to negative feedback was interpreted as a disturbance of higher control processing. Previous trial feedback influenced current processing time, feedback inspection time, and the cardiac acceleration and deceleration responses.

Academic career after treatment for acute lymphoblastic leukaemia

AIM

To evaluate academic career in long term survivors of childhood acute lymphoblastic leukaemia (ALL), in comparison to their healthy siblings.

PATIENTS

Ninety four children treated for ALL with cranial irradiation 18 or 25 Gy and intrathecal methotrexate as CNS prophylaxis. Median age at evaluation was 20 years; median follow up since diagnosis was 15 years at the time of the study.

METHODS

Patients and their 134 siblings completed a questionnaire on school career. The percentage of referrals to special primary schools for learning disabled, and the final level of secondary education in patients and siblings were compared, using a six point classification. Within the patient group, the effect of possible risk factors (age at diagnosis, irradiation dose, and gender) was investigated.

RESULTS

Significantly more patients than siblings were placed in special educational programmes. A significant difference was found for level of secondary education. No effect of gender or irradiation dose was found, but younger age at diagnosis was significantly related to both referrals and school levels.

CONCLUSION

Treatment for childhood ALL with cranial irradiation and chemotherapy at a young age is clearly associated with poorer academic career.

Effects of lovastatin on cognitive function and psychological well-being

PURPOSE

Animal research and cross-sectional studies suggest that serum lipid concentrations may influence cognitive function, mood, and behavior, but few clinical trials have studied these effects.

SUBJECTS AND METHODS

In this double-blind investigation, 209 generally healthy adults with a serum low-density-lipoprotein (LDL) cholesterol level of 160 mg/dL or higher were randomly assigned to 6-month treatment with lovastatin (20 mg) or placebo. Assessments of neuropsychological performance, depression, hostility, and quality of life were conducted at baseline and at the end of the treatment period. Summary effect sizes were estimated as z scores on a standard deviation (SD) scale.

RESULTS

Placebo-treated subjects improved between baseline and posttreatment periods on neuropsychological tests in all five performance domains, consistent with the effects of practice on test performance (all P <0.04), whereas those treated with lovastatin improved only on tests of memory recall (P = 0.03). Comparisons of the changes in performance between placebo- and lovastatin-treated subjects revealed small, but statistically significant, differences for tests of attention (z score = 0.18; 95% confidence interval (CI), 0.06 to 0.31; P = 0.005) and psychomotor speed (z score = 0.17; 95% CI, 0.05 to 0.28; P = 0. 004) that were consistent with greater improvement in the placebo group. Psychological well-being, as measured several ways, was not affected by lovastatin.

CONCLUSION

Treatment of hypercholesterolemia with lovastatin did not cause psychological distress or substantially alter cognitive function. Treatment did result in small performance decrements on neuropsychological tests of attention and psychomotor speed, the clinical importance of which is uncertain.

Conceptual and methodological challenges in discourse assessment with TBI speakers: towards an understanding

The primary objective of this paper is to review theoretical and methodological literature pertaining to the clinical evaluation of discourse abilities in speakers who have sustained traumatic brain injury (TBI). A brief history of the study of discourse impairment in this population is followed by consideration of the following issues: (1) sampling (genres selected, the physical setting in which sampling takes place, the relationship between speakers, elicitation techniques, presence of recording devices, the number of samples required, and transcription); (2) measurement; (3) the relationship between sampling and measurement; (4) other approaches to discourse assessment (self and close other report); (5) consideration of the criterion of 'normal' which clinicians should employ; (6) the relationship between discourse impairment and measures of executive function; and (7) the relationship between discourse impairment and seventy of injury. Recommendations arising from a critical review of these domains are made for both clinical practice and research.

Neuropsychological functioning in nonreferred siblings of children with attention deficit/hyperactivity disorder

The goal of this study was to assess neuropsychological functioning in nonreferred siblings of children with attention deficit/hyperactivity disorder (ADHD). Participants were 156 siblings of ADHD probands with (N = 40) and without (N = 116) ADHD (according to criteria of the Diagnostic and Statistical Manual of Mental Disorders (3rd edition, revised; American Psychiatric Association, 1987) and 118 siblings of non-ADHD normal controls of similar age, IQ, and grade level. Information on attention, executive, and memory functions was obtained in a standardized manner without knowledge of clinical status. Compared with siblings of controls, siblings with ADHD were significantly impaired on the Stroop test and on verbal learning and memory. In contrast, siblings without ADHD were similar to controls on virtually all measures. These data suggest that some executive, attention, and verbal learning deficits are found in nonreferred individuals with ADHD but that neuropsychological deficits are unlikely to constitute an endophenotype to ADHD.

Crossed-uncrossed difference in simple reaction times to lateralized flashes: between- and within-subjects variability

In unimanual reaction times (RT) to lateralized flashes, contralateral responses tend to be slower than ipsilateral responses. This has been called Crossed-Uncrossed Difference (CUD). The CUD tends to show variability across subjects and across studies, but until now the stability of the CUD in an individual subject has not been investigated. To address the role of inter- and intra-subject variability in the CUD, three normal right handers were tested over 50 experimental sessions of 800 trials each, for a total of 40,000 trials of simple reaction times to lateralized flashes. In each subject, CUDs were computed for each session, over two, three, or more sessions, and over the entire dataset. These CUDs were then compared to the CUDs obtained in a group of 15 normal right handers, each tested once in a single session. Results show that: (i) CUD variability across several sessions in a single subject mimics the variability observed in a sample of subjects tested in a single session; (ii) this variability is considerably reduced when the CUD is computed over at least 2400 trials per subject; (iii) CUDs computed over 2400 and up to 12,000 of trials tend to be extremely similar ( approximately 2 ms) across the three subjects tested here; (iv) when reaction times are ordered from the fastest to the slowest and divided into bins, the CUD is remarkably stable over the entire reaction time distribution; and (v) in contrast to the variability of the CUD, the variability for crossed and uncrossed responses across several sessions in a single subject is small and does not mimic the variability observed in a sample of subjects tested in a single session. Taken together, these data suggest that the intersubject variability in the CUD observed in single experimental sessions does not represent a reliable intersubject difference and that the CUD computed over thousands of trials reflects hard-wired mechanisms of callosal transmission.

Detecting exaggeration and malingering in neuropsychological assessment

Magnification of symptoms or nonoptimal effort on neuropsychological tests, within the context of head injury litigation, can have several independent or related underlying causes. Therefore, detecting exaggeration does not automatically indicate that the individual is malingering. This article reviews the evaluative and differential diagnostic process and provides the clinician with suggestions regarding assessment methods. A forensic evaluation that does not include careful consideration of possible negative response bias should be considered incomplete.

Long-term dysfunction following diffuse traumatic brain injury in the immature rat

Children often suffer sustained cognitive dysfunction after severe diffuse traumatic brain injury (TBI). To study the effects of diffuse injury in the immature brain, we developed a model of severe diffuse impact (DI) acceleration TBI in immature rats and previously described the early motor and cognitive dysfunction posttrauma. In the present study, we investigated the long-term functional ability after DI (150 gm/2 m) compared to sham in the immature (PND 17) rat. Beam balance and inclined plane latencies were measured daily for 10 days after injury to assess gross vestibulomotor function. The Morris water maze (MWM) paradigm was evaluated monthly up to 3 months after DI and sham injuries. Reduced latencies on the balance beam and inclined plane were observed in DI rats (p < 0.05 vs. sham [n = 10 per group]) at 24 h and persisted for 10 days postinjury. DI produced sustained MWM performance deficits (p < 0.05 vs. sham) as indicated by the greater latencies to find the hidden platform remarkably through 90 days after injury. Lastly, the brain and body weights of the injured animals were less than sham (p < 0.05) after 3 months. We conclude that a diffuse TBI in the immature rat: (a) created a consistent, marked, but reversible motor deficit up to 10 days following injury; (b) produced a long-term, sustained performance deficit in the MWM up to 3 months posttrauma; and (c) affected body and brain weight gain in the developing rat through 3 months after injury. This TBI model should be useful for the testing of novel therapies and their effect on long-term outcome and development in the immature rat.

Cocaine-associated stroke: three cases and rehabilitation considerations

Cocaine-associated stroke (CAS) is an important cause of disability, especially among younger adults. Improved management has increased survival but little has been discussed about rehabilitation, including medication management. Therefore, experience and therapeutic drug management are described during inpatient rehabilitation with three patients with CAS. Case 14 is a 50-year-old male with a history of hypertension who presented with right hemiparesis, aphasia and depression. He was treated with paroxetine for depression and bromocriptine for poor initiation with a good response, improving by 50 FIM points in 44 days. Case 2 is a 44 year-old female with quadriparesis, aphasia, and deficits in attention and initiation. Methylphenidate for attention deficits and bromocriptine for poor initiation was associated with an excellent functional gain (50 FIM points in 37 days). She eventually returned to work. Case 3 is a 46-year-old female with a history of hypertension who presented with right hemiparesis, aphasia and depression. Without neuropharmacologic intervention, she gained 35 FIM points during an uneventful 47 day rehabilitation stay. Acutely, cocaine can induce cerebral vasoconstriction, cerebrovascular spasm, cerebral vasculitis and intracerebral haemorrhage. Chronic use depletes and destroys dopaminergic pathways, which may be a major factor in depression, and attention and initiation deficits-all observed in these cases. Generally, rapid improvements were seen in mood and cognition in two cases where medication was used. Based on the current literature and pathophysiology of CAS, it is suggested that trials of dopaminergic agents for cognition and extremely cautious use of buproprion for depression may be warrented. Details of the above cases and the practical and theoretical issues of neuropharmacologic intervention in CAS are discussed.

Factors associated with self-concept in children with asthma

PURPOSE

To investigate the relationship of demographic asthma, family, and child factors with self-concept in children with asthma.

METHODS

Data were collected twice approximately 4 years apart from both the affected children and their mothers (N = 134) via interviews and self-report questionnaire.

FINDINGS

Children who demonstrated more negative attitudes toward their illness, had less satisfaction with family relationships, and used more negative coping behaviors had the poorest self-concepts. Over time, the greatest improvement in self-concept occurred in children whose attitudes and satisfaction with family relationships improved and whose use of negative coping behaviors decreased.

CONCLUSIONS

Results suggest that some children with asthma, especially girls with severe asthma, appear to be at risk for poor self-concept.

The effects of propranolol on cognitive function and quality of life: a randomized trial among patients with diastolic hypertension

PURPOSE

We sought to determine whether propranolol has adverse effects on cognitive function, depressive symptoms, and sexual function in patients treated for diastolic hypertension.

SUBJECTS AND METHODS

We performed a placebo-controlled trial among 312 men and women, 22 to 59 years of age, who had untreated diastolic hypertension (90 to 104 mm Hg). Patients were randomly assigned to treatment with propranolol (80 to 400 mg/day) or matching placebo tablets. Thirteen tests of cognitive function were assessed at baseline, 3 months, and 12 months. Five tests measured reaction time to, or accuracy in, interpreting visual stimuli; one test measured the ability to acquire, reproduce, and change a set of arbitrary stimulus-response sets; and seven tests measured memory or learning verbal information. Depressive symptoms and sexual function were assessed by questionnaires at baseline and 12 months.

RESULTS

There were no significant differences by treatment assignment for 11 of the 13 tests of cognitive function at either 3 or 12 months of follow-up. Compared with placebo, participants treated with propranolol had slightly fewer correct responses at 3 months (33 +/- 3 [mean +/- SD] versus 34 +/- 2, P = 0.02) and slightly more errors of commission at 3 months (4 +/-5 versus 3 +/- 3, P = 0.04) and at 12 months (4 +/- 4 versus 3 +/- 3, P = 0.05). At 12 months, depressive symptoms and sexual function and desire did not differ by treatment assignment.

CONCLUSIONS

Treatment of hypertension with propranolol had limited adverse effects on tests of cognitive function that were of questionable clinical relevance, and there were no documented adverse effects on depressive symptoms or sexual function. Selection of beta-blockers for treatment of hypertension should be based on other factors.

Neurocognitive functioning in children with mild and moderate asthma in the childhood asthma management program. The Childhood Asthma Management Program (CAMP) Research Group

BACKGROUND

The Childhood Asthma Management Program (CAMP) is a multicenter double-blind, randomized, placebo-controlled, clinical trial of two anti-inflammatory agents and placebo in children with mild and moderate asthma.

OBJECTIVE

The interrelationship between asthma severity and neurocognitive functioning among 1041 children (age range, 5-12 years) enrolled in the CAMP trial was examined.

METHODS

Asthma severity was established at baseline with a clinical history of asthma symptomatology and measures of lung function (spirometry and methacholine challenge). Diary cards were used in a screening to record nighttime awakenings and doctor contacts caused by asthma symptoms, symptom severity, and number of puffs from a rescue inhaler. All children received a comprehensive neurocognitive assessment at the end of the 28-day screening period (before randomization), including measures of intelligence, attention, memory, and academic achievement.

RESULTS

Significant differences were found between children with mild and moderate asthma on lung function and symptom outcome variables (log(e)FEV(1)PC(20), DeltaFEV(1) percent predicted, change in peak flow percent predicted, nighttime awakenings caused by asthma, average symptom severity score, and average daily number of puffs from a rescue inhaler) but not on neurocognitive variables. Multiple regression analyses revealed that asthma outcomes could not be predicted by neurocognitive variables despite controlling for socioeconomic status. The prevalence of neurocognitive dysfunction, as indicated by the use of psychostimulant medication, was found to be consistent with that found in the existing literature.

CONCLUSION

Mild and moderate asthma symptoms are not related to neurocognitive functioning in the children enrolled in CAMP. Mean performance on neurocognitive variables was found to be similar to that of national normative data.

Detection of feigned recognition memory impairment using the old/new effect of the event-related potential

Twenty-four undergraduate university students with no known neurological disorders completed the Recognition Memory Test (Warrington, A., 1984. Recognition Memory Test manual. Windsor, Berkshire: NFER-Nelson.) while event-related potentials (ERPs) were recorded. Twelve subjects were instructed to feign a recognition memory deficit (malingering group), while the remainder served as controls. The malingerers performed poorly on the test compared to the control group. The 'old/new effect', an ERP measure thought to reflect recognition memory processes, did not differ between the groups, indicating recognition of previously learned material in the malingering group despite poor test performance. The study also revealed a second, early, old/new effect, maximal at left frontal sites in the malingering relative to the control group, suggesting task-related processing differences between the two groups. These effects appear to be of potential value in the detection of malingering of cognitive impairment in the clinical situation.

Eating disorders: psyche or soma?

Speculation about the etiology of eating disorders has gone through different phases, variously favoring familial, organic, and psychosocial factors. Recent evidence has particularly contributed to our understanding of the organic view. We review the evidence for an organic contribution to the illness and present a series of cases in which organic factors were present. The cases illustrate the complex interaction between biological and psychological factors. In particular, a growth hormone-producing pituitary adenoma was discovered in a patient following successful treatment of her bulimia by psychological means alone. Etiological theories of eating disorders need to encompass both organic and psychosocial factors, allowed to interact in complex ways. Focusing exclusively on either aspect is a disservice to our patients.

Development of nicotinic drug therapy for cognitive disorders

Nicotine, as well as other nicotinic drugs, may provide useful therapeutic treatment for a variety of cognitive impairments including those found in Alzheimer's disease, schizophrenia and attention deficit hyperactivity disorder (ADHD). We have found that nicotine skin patches significantly improve attentional performance in people with these disease states as well as normal nonsmoking adults. Animal models are critical for determining the neurobehavioral bases for nicotinic effects on cognitive function. We have found in lesion and local infusion studies with rats that the hippocampus is an important substrate for nicotinic effects on working memory function. Both alpha7 and alpha4beta2 nicotinic receptors in the hippocampus are involved. Further work has investigated the relationship of nicotinic systems with dopaminergic and glutaminergic systems in the basis of cognitive function. Nicotine has proven to be a useful prototypic compound for the family of nicotinic compounds. It produces cognitive improvements in both animal models and clinical populations. Recent work with more selective nicotinic receptor agonists and antagonists in animal models is providing important information concerning the neural mechanisms for nicotinic involvement in cognitive function and opening avenues for development of safe and effective nicotinic treatments for clinical use.

Improved conditioned avoidance learning by oxytocin administration in high-emotional male Sprague-Dawley rats

OBJECTIVE

To examine anti-stress-like properties of oxytocin as a means to improve conditioned avoidance learning in a low-performing, high-emotional, stock of Sprague-Dawley male rats.

METHODS

Adult male rats of two stocks of the Sprague-Dawley strain, designated Stock A and Stock B, were treated daily with oxytocin (1 mg kg(-1) s. c.) for 5 days preceding four daily conditioned avoidance acquisition sessions (approximately 20 trials per 15 min session). The Stock B animals were previously characterized as high-emotional based on [1] elevated plasma corticosterone, and lowered plasma oxytocin, levels and [2] decreased reaction time and an increased startle amplitude to an acoustic stimulation. Finally, [3] these animals were unable to acquire a conditioned avoidance response within 5 days of training.

RESULTS

The Stock A animals rapidly and statistically significantly acquired the avoidance behaviour within 4 days of daily training, whereas Stock B animals did not improve over this time period. The avoidance performance of Stock B animals was markedly and statistically significantly improved by the oxytocin pre-treatment, whereas the performance of Stock A animals was not affected by the same oxytocin treatment.

CONCLUSIONS

Pre-treatment with oxytocin markedly improved avoidance learning in the Stock B high-emotional animals. It is suggested that the improvement is due to previously demonstrated anti-stress-like properties of oxytocin, rendering the animals able to successfully cope with the demands of the conditioned avoidance situation.

Visions of clinical assessment: then, now, and a brief history of the future

Perspectives on the discipline of psychological assessment are provided through reflections on a classic article by Hunt (1946), review of current issues, and a projection of changes likely to occur over the next fifty years. Topics covered include the place of idiosyncratic qualitative responses, test design, clinical judgment, managed care, financial efficacy, over emphasis on pathology, treatment planning, status of projectives, ecological validity, relationship between theory and tests, innovations in scale construction, and computer-assisted assessment. Future predictions relate to innovations in computer-assisted assessment, practitioner roles in an increasingly automated environment, the future of traditional tests, and human-rights issues.