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At least 307 records · Page 17Linked to original sources

Infantile autism reviewed: a decade of research.

Progress in the study of infantile autism over the past 10 years was reviewed in terms of classification and diagnosis, relation to other disorders, demographics, parental characteristics, genetics, intelligence, language, perceptual processes, behavioral characteristics, neurobiological, biochemical and pharmacological aspects, behavioral/educational treatment methodologies, prognosis, and theoretical considerations. This decade's research led to the now generally accepted position that infantile autism is a type of developmental disorder accompanied by severe and, to a large extent, permanent intellectual/behavioral deficits. However, its relationship to other forms of developmental disorders and to mental retardation remains to be delineated. Perceptual/cognitive/language defects appear central to the autistic syndrome, but the specific underlying mechanisms are unknown. Most studies indicate that autistic children have more signs of brain dysfunction than do normal children and about the same number as mentally retarded children. The overwhelming evidence suggests that te treatment of choice for maximal benefit to autistic children is a systematic, intrusive behavioral/educational approach. Yet, in spite of significant gains in almost all children treated, the typical prognostic picture is poor in terms of achieving self-supportive adulthood. The parents of autistic children have been found to be essentially similar to parents of children with organic brain disorders, and manifest no psychopathology which conceivably could induce the disorder. The vast majority of theoretical articles appearing in the 1970s proposed some from of neurobiological defect as the causative factor in autism. One of the major goals for future research is to undertake more extensive comparative studies on nonautistic brain dysfunctional children and autistic children that could yield cleared differential behavioral profiles and testable neurobiological hypotheses.

Autistic Disorder↗

Positive and negative syndromes in chronic schizophrenic inpatients.

This study considered whether chronic schizophrenics with positive and negative syndromes represent distinct subtypes. From a survey of 47 schizophrenic inpatients, 18 showed preponderance of productive or deficit features, and four were mixed. The discrete groups were compared on clinical symptoms, cognitive tests, demographic and historical data, and drug side effects. They were significantly distinguished on most criterion symptoms and affect scales but, otherwise, essentially comparable in psychopathology and extrapyramidal symptoms. The tests revealed similar levels of intellectual impairment and visual-motor deficit, yet the negative patients displayed more primitive cognitive mode and greater psychomotor retardation. They also proved older, less educated, more often born in winter-time, hospitalized later in life, and less heavily medicated. The results supported the validity of the positive-negative dimension for identifying schizophrenic subtypes and suggested etiological implications regarding developmental deficiency.

Adult↗

Improving search algorithms by using intelligent coordinates.

We consider algorithms that maximize a global function G in a distributed manner, using a different adaptive computational agent to set each variable of the underlying space. Each agent eta is self-interested; it sets its variable to maximize its own function g(eta). Three factors govern such a distributed algorithm's performance, related to exploration/exploitation, game theory, and machine learning. We demonstrate how to exploit all three factors by modifying a search algorithm's exploration stage: rather than random exploration, each coordinate of the search space is now controlled by a separate machine-learning-based "player" engaged in a noncooperative game. Experiments demonstrate that this modification improves simulated annealing (SA) by up to an order of magnitude for bin packing and for a model of an economic process run over an underlying network. These experiments also reveal interesting small-world phenomena.

Journal Article↗

An unusual cluster of tardive dyskinesia in schizophrenia: association with cognitive dysfunction and negative symptoms.

Factors associated with the emergence or nonemergence of involuntary movements (tardive dyskinesia) during long-term neuroleptic treatment were investigated in an atypical, isolated population of 31 schizophrenic inpatients with an unusually high prevalence of this syndrome. Patients with involuntary movements could not be distinguished from those without such movements by general characteristics or conventional indices of neuroleptic or anticholinergic treatment. However, they were more likely to show either marked cognitive dysfunction or muteness. These findings support the proposal that, at least in schizophrenia, subtle organic changes may contribute to vulnerability to the emergence of involuntary movements.

Adult↗

Cognition, negative symptoms, and diagnosis: a comparison of schizophrenic, bipolar, and control samples.

Forty-six schizophrenic, 22 bipolar, and 26 normal control subjects were administered negative and positive symptoms scales and tests of cognitive function. Test performance was related to diagnosis and to positive and negative symptom ratings within the schizophrenic group. Bipolar patients were significantly superior in cognitive status when compared with all schizophrenic patients, but less so when compared only with those who did not have key negative symptoms (affective nonresponsivity and poverty of speech). The schizophrenic patients with negative symptoms displayed severe impairment, performing significantly worse than the control, bipolar, and other schizophrenic subjects. Negative symptoms thus are significantly implicated in the cognitive inferiority of schizophrenic to bipolar patients. Although the data suggest bipolar patients may also have cognitive deficiencies, these findings are inconclusive and require cross-validation.

Adult↗

Neurological soft signs in first-episode psychosis: a systematic review.

BACKGROUND: Neurological soft signs (NSS) are minor neurological signs indicating non-specific cerebral dysfunction. Their presence has been documented extensively in schizophrenia but not during the first psychotic episode. AIMS: To review studies that have specifically investigated NSS at the time of the first psychotic episode. METHOD: A review of studies investigating neurological function in first-episode psychosis, using a clinical examination. RESULTS: Patients with first-episode psychosis show an excess of NSS, particularly in the areas of motor coordination and sequencing, sensory integration and in developmental reflexes. Furthermore, NSS may be associated with a specific laterality pattern. CONCLUSIONS: More studies on first-onset schizophrenia are needed, evaluating both sensory and motor neurological domains (scoring separately for the two sides of the body), integrating this knowledge with neuroimaging findings and clarifying the role of NSS as markers of cognitive dysfunction.

Antipsychotic Agents↗

Cognitive effects of long-term benzodiazepine use: a meta-analysis.

INTRODUCTION: While benzodiazepines are the most widely used psychotropic drugs, there are relatively few studies that have examined deficits in cognitive functioning after long-term use. The literature that is available is difficult to interpret due to conflicting results as well as a variety of methodological flaws. OBJECTIVE: To systematically evaluate and integrate the available research findings to determine the effect of long-term benzodiazepine use on cognitive functioning using meta-analytical techniques. METHODS: Thirteen research studies that employed neuropsychological tests to evaluate cognitive performance after long-term use of benzodiazepine medication met inclusion criteria. The neuropsychological tests employed in these 13 studies were each categorised as measuring one of 12 cognitive domains. Separate effect sizes were calculated for each of the 12 cognitive categories. Each study was only allowed to contribute one effect size to each cognitive category by averaging together the effect sizes from the same study if more than one type of test was used to measure a particular category. This strategy resulted in equal weight being given to each study per category, regardless of the number of tests in that category. RESULTS: The overall mean number of patients who were benzodiazepine users was 33.5 (SD +/- 28.9) and the mean number of controls was 27.9 (SD +/- 19.6). The duration of benzodiazepine use ranged from 1 to 34 (mean 9.9) years. Long-term benzodiazepine users were consistently more impaired than controls across all cognitive categories examined, with effect sizes ranging in magnitude from -1.30 to -0.42. The mean weighted effect size was -0.74 (SD +/- 0.25). None of the effect sizes had 95% CIs that spanned zero and, therefore, all of these effects were significant and different to zero. CONCLUSION: Moderate-to-large weighted effect sizes were found for all cognitive domains suggesting that long-term benzodiazepine users were significantly impaired, compared with controls, in all of the areas that were assessed. However, this study has several limitations, one being that it includes a relatively small number of studies. Further studies need to be conducted; ideally, well designed, controlled studies that thoroughly investigate certain areas of cognitive functioning and present data in such a way so as to be amenable to inclusion in a meta-analysis. Incorporating the information from these studies into a larger meta-analysis would allow for a more thorough and statistically sound investigation of the effects of moderator variables. The observation that long-term benzodiazepine use leads to a generalised effect on cognition has numerous implications for the informed and responsible prescription of these drugs.

Adolescent↗

Civilian exposure to toxic agents: emergency medical response.

Civilian populations are at risk from exposure to toxic materials as a result of accidental or deliberate exposure. In addition to industrial hazards, toxic agents designed for use in warfare now are a potential hazard in everyday life through terrorist action. Civil emergency medical responders should be able to adapt their plans for dealing with casualties from hazardous materials (HazMat) to deal with the new threat. Chemical and biological warfare (CBW) and HazMat agents can be viewed as a continuous spectrum. Each of these hazards is characterized by qualities of toxicity, latency of action, persistency, and transmissibility. The incident and medical responses to release of any agent is determined by these characteristics. Chemical and biological wardare agents usually are classified as weapons of mass destruction, but strictly, they are agents of mass injury. The relationship between mass injury and major loss of life depends very much on the protection, organization, and emergency care provided. Detection of a civil toxic agent release where signs and symptoms in casualties may be the first indicator of exposure is different from the military situation where intelligence information and tuned detection systems generally will be available. It is important that emergency medical care should be given in the context of a specific action plan. Within an organized and protected perimeter, triage and decontamination (if the agent is persistent) can proceed while emergency medical care is provided at the same time. The provision of advanced life support (TOXALS) in this zone by protected and trained medical responders now is technically feasible using specially designed ventilation equipment. Leaving life support until after decontamination may have fatal consequences. Casualties from terrorist attacks also may suffer physical as well as toxic trauma and the medical response also should be capable of dealing with mixed injuries.

Biological Warfare↗

Development of microcomputer-based mental acuity tests.

Recent disasters have focused attention on performance problems due to the use of alcohol and controlled substances in the workplace. Environmental stressors such as thermal extremes, mixed gases, noise, motion, and vibration also have adverse effects on human performance and operator efficiency. However, the lack of a standardized, sensitive, human performance assessment battery has probably delayed the systematic study of the deleterious effects of various toxic chemicals and drugs at home and in the workplace. The collective goal of the research reported here is the development of a menu of tests embedded in a coherent package of hardware and software that may be useful in repeated-measures studies of a broad range of agents that can degrade human performance. A menu of 40 tests from the Automated Performance Test System (APTS) is described, and the series of interlocking studies supporting its development is reviewed. The APTS tests, which run on several versions of laptop portables and desktop personal computers, have been shown to be stable, reliable, and factorially rich, and to have predictive validities with holistic measures of intelligence and simulator performances. In addition, sensitivity studies have been conducted in which performance changes due to stressors, agents, and treatments were demonstrated. We believe that tests like those described here have prospective use as an adjunct to urine testing for the screening for performance loss of individuals who are granted access to workplaces and stations that impact public safety.

Alcoholic Intoxication↗

NSAIDs: maternal and fetal considerations.

Nonsteroidal anti-inflammatory drugs (NSAIDs) gained popularity in the late 1970s. Inhibition of prostaglandin synthesis with indomethacin has been reported to be effective for prevention of labor and for treatment for symptomatic polyhydramnios. Concern about its possible constrictive effect on the fetal ductus arteriosus has limited its use in pregnancy. Maternal indomethacin therapy has also been associated with reduction in urine production in the fetus and with oligohydramnios. Obstetricians have discouraged pregnant women from taking analgesic doses of aspirin, mainly because of the availability of paracetamol (acetaminophen), which causes less gastric irritation, but also because of fear of maternal and fetal hemorrhage and of possible premature closure of the ductus. These fears largely derive from studies on patients taking large doses and from extrapolation from other NSAIDs. The likelihood that treatment with 60-75 mg/day of aspirin markedly reduces the incidence of preeclampsia and fetal intrauterine growth retardation makes it important to reexamine its use. This review describes the pharmacology and pharmacokinetics of aspirin with particular reference to pregnancy and considers teratogenesis, prolongation of pregnancy and labor, maternal bleeding, fetal and neonatal bleeding, possible effects on the ductus arteriosus and pulmonary circulation, and possible nonspecific effects on intelligence and breast feeding and acute toxicity in the neonate.

Abnormalities, Drug-Induced↗

Diagnosis and treatment of depression in patients with mental retardation.

Depression in mentally retarded individuals is not uncommon and usually is treatable. However, studies of the diagnosis and treatment of psychiatric illnesses in general and depression specifically in this population are relatively rare. Although Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria can be applied to mildly and moderately retarded individuals, the diagnosis of depression in those with intelligence quotients below 35 is challenging. However, the diagnosis of depression in the latter group is possible using modified criteria emphasizing observational data. Criteria include symptoms such as sadness, irritability, decreased social interaction, regression of skills, sleep disturbances, diurnal variation, and aggression. Furthermore, there is a growing body of evidence that antidepressant treatments, especially administration of selective serotonin reuptake inhibitors, are effective in treating depression in mentally retarded patients. This article reviews numerous studies elaborating on the diagnosis, phenomenology, and treatment of depression in mentally retarded individuals.

Aggression↗

Depo Provera: a profile of current users.

This retrospective study reviewed the current users of Depo-Medroxy-Progesterone-Acetate (Depo-Provera) from April to June, 1987, within the Family Planning Association of Victoria's Richmond Clinic. The profile that emerged from the study showed the clients were of average intelligence, well informed, had tried other methods of contraception, had a high number of unplanned pregnancies and chose to use Depo-Provera as other methods of contraception were unsuitable.

Adolescent↗

Intelligence with representation.

Behaviour-based robotics has always been inspired by earlier cybernetics work such as that of W. Grey Walter. It emphasizes that intelligence can be achieved without the kinds of representations common in symbolic AI systems. The paper argues that such representations might indeed not be needed for many aspects of sensory-motor intelligence but become a crucial issue when bootstrapping to higher levels of cognition. It proposes a scenario in the form of evolutionary language games by which embodied agents develop situated grounded representations adapted to their needs and the conventions emerging in the population.

Adaptation, Physiological↗

The Maudsley Bipolar Disorder Project: the effect of medication, family history, and duration of illness on IQ and memory in bipolar I disorder.

BACKGROUND: Despite the growing recognition of the importance of cognitive impairment in psychiatric disorders, the effect of clinical factors, such as medication use and family history of affective disorders, on cognition in bipolar I disorder patients still remains unclear. This study examines the contribution of known and potential predictors to both general intellectual function and memory in a representative population of bipolar I disorder patients. METHOD: Of the 425 patients receiving treatment within a defined catchment area, 63 were identified as having bipolar I disorder. Of these patients, 43 were enrolled in the study and participated in a personal interview by a psychiatrist. All patients were invited to participate in a personal interview by a psychiatrist, and information on family history, past psychiatric history, past and current treatments, duration of illness, and age at onset was collected, in addition to demographic data. Cognitive performance was assessed using the Wechsler Adult Intelligence Scale-Revised, the National Adult Reading Test, and the Wechsler Memory Test III. RESULTS: Forty-three patients with DSM-IV bipolar I disorder were enrolled into the Maudsley Bipolar Disorder Project. Patients on treatment with antipsychotic drugs had a lower current full scale IQ, lower general memory scores, and lower working memory scores. A family history of affective disorders was associated with a higher full scale IQ, but not with either general or working memory measures. Duration of illness was negatively associated with general memory scores, but had no effect on either IQ or working memory measures. CONCLUSION: Current antipsychotic medication, duration of illness, and family history of affective disorder were the most significant predictors of IQ and memory function in bipolar I disorder patients.

Adult↗

Neuropsychological effects of chronic asymptomatic increased lead absorption. A controlled study.

Twenty-seven asymptomatic children with confirmed chronic increased lead absorption were compared with 27 matched control children for evidence of neuropsychological impairment. Evaluation of each child included a complete history, physical examination, quantitative neurological tests, and comprehensive psychological tests. There was significantly increased incidence of hyperactive behavior in the subjects with increased lead levels, but there was no significant difference in any of the quantitative test results. Uncontrolled variables, especially lead absorption in infancy and adverse environmental pressures other than lead, still leave questions about the relationship between chronic lead exposure and behavior of intelligence.

Chelating Agents↗