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PubMed2006

Social/communication skills, cognition, and vocational functioning in schizophrenia.

Deficits in social/communications skills have been documented in schizophrenia, but it is unclear how these deficits relate to cognitive deficits and to everyday functioning. In the current study, social/communication skills performance was measured in 29 schizophrenia patients with a history of good vocational functioning (GVF) and 26 with a history of poor vocational functioning (PVF) using a role-play-based social skills assessment, the Maryland Assessment of Social Competence (MASC). A battery of standard cognitive tasks was also administered. MASC-indexed social skills were significantly impaired in PVF relative to GVF patients (odds ratio = 3.61, P < .001). Although MASC social skills performance was significantly associated with cognitive performance in domains of verbal ability, processing speed, and memory, the MASC nevertheless remained an independent predictor of vocational functioning even after controlling for cognitive performance. Social/communications skills predict vocational functioning history independently of cognitive performance, and social skills measures should be considered for inclusion in test batteries designed to predict everyday functioning in schizophrenia.

Activities of Daily Living↗

PubMed2002

Development and validation of a web-based screening tool for monitoring cognitive status.

OBJECTIVES: We acquired normative data for an Internet neurocognitive screening tool, the Cognitive Stability Index (CSI), and investigated its validity both for initial assessment and for detecting significant change. PARTICIPANTS: Normative data on a nationally representative sample of 284 individuals aged 18 to 89. Validity data was obtained for outpatient groups of mild-to-moderate TBI, attention deficit/hyperactivity disorder (AD/HD), and Alzheimer's disease. RESULTS: The CSI subtests resolve to four factors: attention, processing speed, motor speed, and memory with acceptable psychometric properties. Patterns of scores obtained by three groups of patient-participants provided reasonable evidence of clinical validity for screening and monitoring change. CONCLUSIONS: An Internet-based system holds promise for applying complex statistical models for routine monitoring of cognitive function.

Adolescent↗

PubMedDate not supplied

Bromocriptine in the treatment of post-polio fatigue: a pilot study with implications for the pathophysiology of fatigue.

Fatigue is the most commonly reported and most disabling of all post-polio sequelae (PPS). Bromocriptine mesylate (Parlodel) was employed in a placebo-controlled trial in five survivors of paralytic polio who continued to report moderate to severe daily fatigue after complying with the conservative treatments prescribed for PPS. Placebo was given for 4 wk followed by increasing doses of bromocriptine mesylate, administered at 12:00 pm for 28 days, which reached a total dose of 12.5 mg/day. Three subjects reported marked symptom improvement on bromocriptine but not on placebo. Their reported difficulty with attention, concentration, word finding, mind wandering, memory, thinking clearly, and fatigue on awakening was significantly negatively correlated with days on bromocriptine but not with days on placebo. Before the drug trial began, responders had clinically impaired performance on neuropsychologic tests of attention and information processing speed, more than twice as many hyperintensities on magnetic resonance imaging of the brain, abnormally low fasting adrenocorticotropic hormone levels, and nearly double the mean plasma prolactin level compared with nonresponders. The implications of these findings for the pathophysiology of fatigue are discussed. A double-blind, placebo-controlled, multicenter study will be needed to confirm bromocriptine's efficacy in treating attentionally and neurophysiologically impaired polio survivors whose severe and disabling fatigue does not respond to conservative therapies.

Adrenocorticotropic Hormone↗

PubMedDate not supplied

Chronic fatigue syndrome: a literature review from a physiatric perspective.

To examine the literature on chronic fatigue syndrome (CFS), especially as it relates to cognitive deficits and exercise, more than 200 articles related to CFS were selected from computer-based research as well as pertinent articles noted in the references of individual articles. All were relevant articles on CFS, although articles in a foreign language were excluded. CFS is a controversial diagnosis of exclusion, but certain subgroups do appear to exist. It may represent multiple diseases or multiple stages of the same disease. Although cognitive deficits are commonly reported, the measured impairments are relatively subtle and are in the area of complex information processing speed, or efficiency. Magnetic resonance imaging, single-photon emission computer tomography, and neuroendocrine studies present preliminary evidence suggestive of the cerebral involvement primarily in the white matter. The weakness and fatigue may be the result of alterations in the central nervous system, not in the peripheral muscles. However, it is hard to separate the documented weakness and endurance deficits from deconditioning. Autonomic symptoms such as orthostatic intolerance and a predisposition to neurally mediated syncope may be explained by cardiovascular deconditioning, a postviral idiopathic autonomic neuropathy, or both. The review points out the need for more carefully designed studies of CFS that focus on the relationship between neuropathology, psychopathology and neuropsychologic functioning. The role of exercise as a stimulus for exacerbation or in treatment needs to be further studied using clear diagnostic criteria as well as control groups that carefully match the activity level.

Activities of Daily Living↗

PubMed2005

Analysis of the results of functional electrical stimulation on hemiplegic patients' upper extremities using the Minnesota manual dexterity test.

To study the influence of functional electric stimulation (FES) on grip acquisition and on the change of grip processing speed, 38 hemiplegic patients took part in the rehabilitation program of the Division of Rehabilitation Medicine of the Hospital das Clinicas, School of Medicine, University of Sao Paulo. Half of the patients received FES on their wrist and finger extensor muscles. The patients in this study were evaluated initially, then after 3 months and after 6 months using the Minnesota manual dexterity test. We concluded that the time necessary for use of FES to generate a significant improvement in the grip speed in hemiplegic patients is 6 months, using twice-weekly administration of stimulation.

Analysis of Variance↗

PubMedDate not supplied

Caffeine effects on learning, performance, and anxiety in normal school-age children.

OBJECTIVE: The purpose of this investigation was to study the acute effects of caffeine on learning, performance, and anxiety in normal prepubertal children. METHOD: Twenty-one children were evaluated in a double-blind, placebo-controlled crossover design. Subjects were studied during four sessions, 1 week apart, under the following conditions: baseline, placebo, 2.5 mg/kg caffeine, and 5.0 mg/kg caffeine. Subjects were randomized to order of placebo and the two dosages of caffeine. Dependent measures included tests of attention, manual dexterity, short-term memory, and processing speed. Anxiety rating scales were also administered. Saliva samples were analyzed for caffeine levels. RESULTS: Caffeine improved performance on two of four measures of the Test of Variables of Attention and on a test of manual dexterity in the dominant hand. There was a trend toward increased current level of self-reported anxiety after caffeine on a visual analogue measure of anxiety. Children reported feeling significantly less "sluggish" after caffeine ingestion than after placebo ingestion. CONCLUSIONS: In a small sample size, there was indication that caffeine enhanced performance on a test of attention and on a motor task. Children also reported feeling less "sluggish" but somewhat more anxious. Because caffeine is so widely available and frequently consumed by children, these results are important and need replication.

Anxiety↗

PubMed1998

Caffeine withdrawal in normal school-age children.

OBJECTIVE: Caffeine is widely consumed by children around the world. The purpose of this study was to determine whether children manifest withdrawal effects after cessation of caffeine intake. METHOD: Thirty normal children completed the single-blind, within-subjects, repeated-measures study with weekly sessions. Subjects were tested four times: (1) baseline (on regular caffeine diet); (2) on caffeine (approximately 120 to 145 mg/day); (3) during withdrawal (24 hours after discontinuation of caffeine taken for 13 consecutive days); and (4) at return to baseline. Subjects were evaluated with self-report measures of symptoms and objective measures of attention, motor performance, processing speed, and memory. RESULTS: During caffeine withdrawal, there was a significant deterioration on response time of a visual continuous performance test of attention. This finding is consistent with caffeine withdrawal. The deterioration in response time appeared to persist for 1 week. CONCLUSIONS: Twenty-four hours after children discontinued caffeine, there was a decrease in performance on reaction time of a task requiring sustained attention. Further work is indicated to determine whether children manifest caffeine withdrawal effects after cessation of caffeine intake.

Analysis of Variance↗

PubMed2001

Psychiatric, psychosocial, and cognitive functioning of female adolescents with ADHD.

OBJECTIVE: To characterize the psychiatric, psychosocial, and cognitive functioning of female adolescents with attention-deficit/hyperactivity disorder (ADHD) in comparison with female controls and males with ADHD. Female controls were also compared with male controls to verify gender differences in a nonclinical sample. METHOD: One hundred seven adolescents from Southern Ontario aged 13 to 16 were included: 24 females with ADHD, 35 males with ADHD, 28 control females, and 20 control males. All were assessed with semistructured interviews, questionnaires, and tests of achievement and intellectual functioning. RESULTS: After controlling for parental education and estimated Full Scale IQ, females with ADHD were more impaired than control females in depression, anxiety, distress, teacher relationships, stress, attributional styles, and locus of control and on all cognitive and achievement measures. Females with ADHD were more impaired than males with ADHD in self-reported anxiety, distress, depression, locus of control, and vocabulary scores. These group differences were confirmed by higher ratings by parents and teachers in symptoms of psychopathology. Males with ADHD were more impaired in processing speed. Some gender differences (locus of control and vocabulary scores) were eliminated when controlling for ADHD severity. The absence of any differences between male and female controls indicates gender differences were specific to the clinical groups. CONCLUSION: Females with ADHD are at high risk for more psychological impairment than both males with ADHD and control females. The identified psychosocial problems point to areas for intervention.

Achievement↗

PubMed2000

Memory, attention, function, and mood among patients with chronic posttraumatic stress disorder.

We report a study of memory, attention, function, and mood among 36 male Vietnam War Veterans suffering from chronic posttraumatic stress disorder (PTSD). PTSD subjects (N = 36) were in good physical health, suffering from moderate depression, and not knowingly suffering from other mental disorders. Control subjects (N = 18) were in good physical health, not knowingly suffering from a mental disorder, and matched with PTSD subject for age, sex, and level of education. Assessment instruments for PTSD subjects included the PostTraumatic Stress Diagnostic Scale (clinician administered), the Hamilton Depression Rating Scale (clinician administered), and the Cognitive Evaluation Protocol (CEP), a touchscreen computer assessment instrument that is self-administered by subjects. CEP was administered twice to PTSD subjects 1 month apart; other instruments were administered at the beginning of the study. Control subjects took CEP once and were administered the Hamilton Depression Rating Scale and the PostTraumatic Stress Diagnostic Scale once. Compared with control subjects, PTSD subjects performed significantly less well on CEP for the three cognitive domains of attention, memory, and function and had highly elevated depression scores. An interaction between depression and memory was found but not with depression and attention. There was no evidence of reduced information processing speed among PTSD subjects. Comparisons between the three assessment instruments showed a high degree of cross-assessment agreement. The findings are consistent with reports that chronic PTSD is associated with compromised memory, attention, and function. The study documents the feasibility of using self-administrated touchscreen computer programs to evaluate and track features of mental disorders.

Affect↗

PubMed1999

Traumatic brain damage in minor head injury: relation of serum S-100 protein measurements to magnetic resonance imaging and neurobehavioral outcome.

OBJECTIVE: The present study was conducted to validate S-100 protein as a marker of brain damage after minor head injury. METHODS: We studied 50 patients with minor head injuries and Glasgow Coma Scale scores of 13 to 15 in whom computed tomographic scans of the brain revealed no abnormalities. Serum levels of S-100 protein were measured at admittance and hourly thereafter until 12 hours after injury. Magnetic resonance imaging and baseline neuropsychological examinations were performed within 48 hours, and neuropsychological follow-up was conducted at 3 months postinjury. RESULTS: Fourteen patients (28%) had detectable serum levels of S-100 protein (mean peak value, 0.4 microg/L [standard deviation, +/- 0.3]). The S-100 protein levels were highest immediately after the trauma, and they declined each hour thereafter. At 6 hours postinjury, the serum level was below the detection limit (0.2 microg/L) in five (36%) of the patients with initially detectable levels. Magnetic resonance imaging revealed brain contusions in five patients, four of whom demonstrated detectable levels of S-100 protein in serum. The proportion of patients with detectable serum levels was significantly higher when magnetic resonance imaging revealed a brain contusion. In patients with detectable serum levels, we observed a trend toward impaired neuropsychological functioning on measures of attention, memory, and information processing speed. CONCLUSION: Determination of S-100 protein levels in serum provides a valid measure of the presence and severity of traumatic brain damage if performed within the first hours after minor head injury.

Adolescent↗

PubMed2000

Lower cognitive performance of older football players possessing apolipoprotein E epsilon4.

OBJECTIVE: To determine whether the cognitive status of professional football players varies as a function of age and apolipoprotein E (APOE) genotype. METHODS: Fifty-three active players underwent APOE and neuropsychological assessments. Players were grouped according to age (proxy indicator of high/low exposure to contact) and the presence/absence of at least one copy of the epsilon4 allele. Outcome measures were overall cognitive performance and scores in cognitive domains. RESULTS: As a group, older players possessing APOE epsilon4 exhibited significantly lower cognitive test scores than did all other players studied, including non-epsilon4-possessing players and younger epsilon4-carriers. Measures of general cognitive functioning, information-processing speed and accuracy, and attention were related to poorer performance among the epsilon4-carrying players. In an analysis of variance model, the interaction between APOE genotype and age was significant (P = 0.004). As determined using linear regression, age accounted for 34% of the variance in the memory index among APOE epsilon4-possessing players but did not contribute significantly to variance among the non-epsilon4-possessing players. Older APOE epsilon4-carriers were significantly overrepresented among players whose scores indicated possible cognitive impairment, with the criterion of performing two or more standard deviations below the general normal values in a summary index of general cognitive functioning. CONCLUSION: Older professional football players who possessed the APOE epsilon4 allele scored lower on cognitive tests than did players without this allele or less experienced players of any genotype. The cognitive status of professional athletes with repeated exposure to head trauma may therefore be influenced by age, inherited factors such as APOE genotype, and cumulative exposure to contact.

Adult↗

PubMed1990

Effects of monocular occlusion on neural and motor response times for two-dimensional stimuli.

Previous studies have shown that there are advantages associated with the simultaneous use of both eyes to view two-dimensional stimuli. To investigate further this binocular advantage, three experiments were conducted using male and female names presented on a video display as stimuli. In the first experiment, simple reaction times (RT's) were found to increase by about 6% as a result of monocular occlusion. In the second experiment, visual evoked response (VER) and P300 implicit times were also found to increase as a result of occlusion. The third experiment confirmed these results and investigated the sensitivity of evoked potential techniques to changes in stimulus complexity. The three experiments demonstrate that monocular occlusion does have a significant effect on processing speed for two-dimensional visual stimuli. The major portion of this effect (62%) is manifest at the level of the visual cortex, and is not perceived by subjects as significantly increasing the mental workload associated with generating responses to these stimuli.

Adult↗

PubMed2004

Column-switching procedures for the fast analysis of drugs in biologic samples.

Liquid chromatography coupled with mass spectrometry in single and dual mode (LC-MS and LC-MS/MS) is the method of choice for the quantification of drugs and their metabolites in biologic fluids. Following the new challenges encountered in the process of drug development, liquid chromatography-mass spectrometry has been found to achieve high-throughput analysis. With this impressive tool, the sample preparation step before analysis is simplified, and the analytic process speeded up. Several generic approaches have recently been developed for the sample extraction coupled on line with a LC-MS system. In this paper, different extraction supports allowing the direct injection of biologic fluids were investigated, namely, restricted-access media, large-size particle, and monolithic phases. In the column-switching configuration, these supports, coupled with microbore analytic columns, were found suitable for the fast analysis (total analysis time of less than 10 minutes) of different drugs and their metabolites in biologic matrices at the nanogram per milliliter level.

Chromatography, Liquid↗

PubMed1995

Neuropsychology of multiple sclerosis.

Neuropsychological investigations have demonstrated that cognitive disorders are common (45-65%) in patients with multiple sclerosis. This review summarizes our current understanding of the nature and etiology of these disorders. Specifically, neuropsychological deficits regularly occur on measures of recent memory, attention, information-processing speed, executive functions, and visuospatial perception. In contrast, general intelligence, language, and certain aspects of memory (short-term capacity and implicit) are preserved. The degree and pattern of cognitive dysfunction is highly correlated with the amount and location of white-matter disease within the cerebral hemispheres. Natural history studies indicate that changes in cognitive test performance are correlated with increasing lesion load on magnetic resonance imaging. The development of brief cognitive-testing instruments for clinical screening and measuring treatment effects in clinical trials is underway. A clear weakness in the literature is the dearth of studies evaluating potential treatments for cognitive disorders.

Brain↗

PubMed2005

A review of cognitive impairment and cerebral metabolite abnormalities in patients with hepatitis C infection.

Numerous studies have reported associations between chronic hepatitis C virus (HCV) infection and fatigue, depression and impairments in health-related quality of life, which are independent of the severity of liver disease. Although there are a large number of potential explanations for these symptoms, including a history of substance abuse and associated personality types, or the effect of the diagnosis of HCV infection itself, there has been recent interest in the possibility of a biological effect of HCV infection on cerebral function. There is emerging evidence of mild, but significant neurocognitive impairment in HCV infection, which cannot be wholly attributed to substance abuse, co-existent depression or hepatic encephalopathy. Impairments are predominantly in the domains of attention, concentration and information processing speed. Furthermore, in-vivo cerebral magnetic resonance spectroscopy studies in patients with hepatitis C and normal liver function have reported elevations in cerebral choline-containing compounds and reductions in N-acetyl aspartate, suggesting that a biological mechanism may underlie the cognitive findings. The recent detection of HCV genetic sequences in post-mortem brain tissue raises the intriguing possibility that HCV infection of the central nervous system may be related to the reported neuropsychological symptoms and cognitive impairment.

Brain↗

PubMed2004

Fast, but error-prone, responses during acute alcohol intoxication: effects of stimulus-response mapping complexity.

BACKGROUND: Although moderate doses of alcohol can impair performance on tasks that require information processing, little is known about the locus of the alcohol effects within the processing stream. This study used a psychological refractory period paradigm to investigate the effect of alcohol on the central, cognitive stage of information processing when task complexity is manipulated by altering stimulus-response compatibility. METHODS: Thirty-four healthy male social drinkers were assigned to one of two groups (n = 17) that performed two tasks. Each trial consisted of a task 1 stimulus (tone) followed by a task 2 stimulus (letter) that was presented after one of four stimulus onset asynchronies (50, 200, 500, or 1100 msec). A baseline test of performance was obtained before the groups received a beverage containing either 0.0 g/kg (placebo) or 0.65 g/kg alcohol. Both groups were retested when blood alcohol concentration (BAC) was increasing and was decreasing. RESULTS: The alcohol group made significantly more errors in task 1 compared with their drug-free baseline measure during the ascending phase of the BAC curve, and error rates increased to a greater extent for the more complex arbitrary stimulus-response mapping condition. Moreover, this increase in errors continued unabated during the descending phase of the BAC curve. Increasing BACs also slowed performance (longer reaction time), but unlike errors, reaction time returned to drug-free baseline levels when BAC was decreasing. CONCLUSIONS: The results provide evidence that an acute dose of alcohol can impair one aspect of the central, cognitive stages of information processing. The possibility that errors in information processing remain during decreasing BACs even after processing speed has returned to drug-free levels has important practical implications relating to the detrimental consequences of acute alcohol intoxication.

Adult↗

PubMed2005

Cognitive outcome in traumatic brain injury survivors.

PURPOSE OF REVIEW: This review discusses recent studies investigating the cognitive and psychiatric outcome of posttraumatic brain injury. In addition, it aims to highlight key areas for future research. RECENT FINDINGS: Detailed cognitive assessments have revealed particular deficits in processing speed in the visual domain and the detrimental impact of interference on attentional performance. A pilot functional imaging study revealed neural changes in survivors performing a response inhibition task, even when matched to controls on behavioural indices. Recent psychiatric studies highlight the incidence of these disorders in the survivors and attempt to characterize distinct psychiatric profiles. Adult and child survivors appear to show differential difficulties. Successful rehabilitation strategies addressing these psychiatric and cognitive deficits include holistic intensive neuropsychological interventions and the introduction of electronic devices. Systematic randomized trials are needed to provide an adequate evidence base for clinical practice. The potential for cognitive enhancement using psychopharmacological agents has yet to be exploited. These treatments may lead to improved quality of life for traumatic brain injury survivors and their families. SUMMARY: Survivors of head injury show a diverse pattern of cognitive and psychiatric profiles. Recent research highlights the nature of some of these deficits and possible ways to enhance functioning. However, the area is well poised for rapid progress in the understanding of cognitive and emotional dysfunction following traumatic brain injury (TBI) and its rehabilitation through neuropsychological and psychopharmacological means.

Brain Injuries↗

PubMed2005

Chronic neurocognitive effects of critical illness.

PURPOSE OF REVIEW: Until relatively recently critical care practitioners have focused on survival of their patients and not long-term outcomes. An increasing body of research has examined patient outcomes beyond discharge from the intensive care unit and hospital. One area of focus is neurobehavioral outcomes including neurocognitive sequelae and neuropsychiatric disorders such as depression and anxiety. Cognitive functions are brain-based or mental activities that involve acquiring, storing, retrieving, and using information and include domains such as memory, attention, executive function, mental processing speed, spatial abilities, and general intelligence. It is known from other medical specialties that impaired cognitive function can have a broad, substantial, and long-lasting impact on a patient's life. This paper examines the current evidence for neurocognitive impairments in survivors of critical illness. RECENT FINDINGS: Recent studies support the hypothesis that critical illness can lead to significant impairments in neurocognitive function. Current work indicates that the neurocognitive impairments can last for months or years after a patient arrives home and may have important consequences for quality of individual and family life and for ability to return to work as well as substantial economic costs. The mechanisms of neurocognitive impairments are not fully understood, but in acute respiratory distress syndrome hypoxemic burden appears important. SUMMARY: Among the potential consequences of critical illness are now included neurocognitive impairments. Future research should include the search for strategies for the early identification of neurocognitive impairments, mechanisms of brain injury, and therapeutic modalities designed to prevent or decrease neurocognitive morbidity.

Anesthesia↗