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991.
Motor control and cerebral hemispheric specialization in highly qualified judo wrestlers 总被引:1,自引:0,他引:1
With the purpose of investigating motor and cognitive lateralization profiles associated with long-term motor training, we investigated differences in hemispheric specialization between proficient judo sportsmen and controls through the assessment of a number of handedness and footedness items including postural preferences as well as dichotic listening and lateralized visual field tests. Our data show that: (1) the different handedness and footedness items did differently relate to each other within the athlete and control groups as revealed by a principle component analysis (PCA); (2) stand side correlated differently to these motor profile factors in athletes and controls; (3) athletes preferred more frequently to perform certain movements with the left hand than controls, although overall right-handed; (4) this was especially true for athletes which proved to be most proficient/skilled; and (5) in a lateralized verbal listening task and a lateralized visual field task athletes revealed enhanced right-hemispheric involvement relative to controls. Our results suggest that during motor and postural skill acquisitions (long-term judo training) lateral preferences are modified, probably due to neuroplasticity. Moreover, the present findings support the multidimensional view of handedness by Steenhuis and Bryden [Cortex 25 (1989) 289] and the notion of a right-hemispheric "praxis system" involved in skilled action routines within peripersonal space [Brain and Cognition 23 (1993) 181]. 相似文献
992.
Studies of the relationship between the fragile X (FRAXA) mutation and autism have been controversial. Although there are differences between the two populations, individuals with FRAXA and autism exhibit remarkably similar aberrant behavior patterns. We examined comparably aged children and adolescents with FRAXA or autism to determine whether longitudinal changes in cognitive ability and adaptive behavior were similar in the two groups. We found decreases in IQ scores in young children with FRAXA as well as in those with autism. Declines in IQ scores were steeper among children with FRAXA. Older children and adolescents with autism exhibit stable test-retest scores, whereas older children with FRAXA continue to show decreases. Comparable declines in adaptive behavior composite scores were observed in both groups, at all ages tested, and across all adaptive behavior domains. 相似文献
993.
OBJECTIVE: Over the last decade, various hypotheses have been advanced concerning the cognitive functions affected by chronic alcoholism. The aim of this study was to identify the pattern of executive function impairment in chronic alcoholism, shedding light on possible differences between specific functions related to the frontal lobe. METHODS: Twenty-two male alcoholics and 22 controls, matched for age, educational level and IQ, were enrolled in the study. MMPI and a battery of neuropsychological tests [i.e. digit symbol, trail making test, Stroop test, digit cancellation test, Wisconsin card sorting test (WCST), simple and choice reaction times] for assessing frontal lobe functioning were administered. RESULTS: The alcoholics were found to be impaired in a wide range of executive domains, with the exception of the Stroop test, which nevertheless showed a trend towards statistically significant differences between patients and controls. CONCLUSION: With the exception of aggression - our subjects did not have high aggression scale scores - the 'frontal lobe hypothesis', according to which alcoholic patients are impaired on function tests related to the frontal lobe, was therefore confirmed in our sample. 相似文献
994.
Penadés R Boget T Lomeña F Mateos JJ Catalán R Gastó C Salamero M 《Acta psychiatrica Scandinavica》2002,105(3):202-208
OBJECTIVE: The effects of neuropsychological treatment on cognitive hypofrontality were examined in schizophrenic patients through the score activation. METHOD: Eight subjects (six men and two women) with persistent negative symptoms and cognitive impairments were evaluated with single photon emission computed tomography (SPECT) procedures and neuropsychological battery before and after a neuropsychological treatment group. RESULTS: After treatment an enhancement in neuropsychological performance was found, especially in executive functions. The activation score showed an increase over baseline levels and no cognitive-dependent hypofrontality after treatment was found. Although the prefrontal blood flow changes were small and non-specific, they suggest a reduction of the cognitive hypofrontality after neuropsychological treatment. CONCLUSION: Cognitive improvements after neuropsychological treatment would possibly be related with the diminution of the functional hypoactivity in the prefrontal areas. 相似文献
995.
OBJECTIVE: We suggest that the identification of depression in the medically ill (DMI) might be improved by focussing on cognitive features. METHOD: We recruited 302 patients to complete our provisional cognitive-based measure. Subsets also completed one of two comparator screening measures, either the Hospital and Anxiety Depression Scale (HADS) or the Beck Depression Inventory for Primary Care (BDI-PC). One hundred and sixty patients were then assessed by a psychiatrist who estimated whether they were 'clinically depressed' and who also administered a standardized interview for depression (the CIDI). RESULTS: Analyses identified items discriminating clinically depressed and non-depressed individuals, allowing development of brief (10-item) and extended (18-item) measures. The two new measures were compared with the HADS and the BDI-PC in discriminating depressed and non-depressed medically ill patients. CONCLUSION: A cognitive construct-based approach to assessing depression in the medically ill appears strongly supported. We provide brief (DMI-10) and extended (DMI-18) measures that appear to have utility as screening instruments. Consideration of the discriminating items may also assist clinical decision making. 相似文献
996.
Starace F Bartoli L Aloisi MS Antinori A Narciso P Ippolito G Ravasio L Moioli MC Vangi D Gennero L Coronado OV Giacometti A Nappa S Perulli ML Montesarchio V La Gala A Ricci F Cristiano L De Marco M Izzo C Pezzotti P D'Arminio Monforte A 《Acta psychiatrica Scandinavica》2002,106(1):20-26
OBJECTIVE: To assess the natural story of HIV-associated affective and cognitive disorders and the relationship with clinical, pharmacological, immunological and behavioural factors. METHOD: A total of 395 HIV-positive patients, naive to Highly Active Antirectroviral therapy (HAART), with no severe psychiatric disorders have been enrolled in the Neuro-ICONA Study. All participants were administered a comprehensive data collection instrument including an addiction behaviour survey, a medical problem list, a psychiatric assessment, a validated neuropsychological test battery. RESULTS: The global prevalence of cognitive impairment and of prominent depressive symptomatology were 17.9 and 15.5%, respectively. A significant difference in the prevalence of prominent depressive symptomatology was observed between patients in HAART and those not taking HAART(14.1 vs. 23.8%; P = 0.05). CONCLUSION: Depressive and cognitive disorders affect a substantial proportion of HIV-seropositive subjects. The prevalence of prominent depressive symptomatology appears to significantly vary in relationship to the therapeutic protocol. 相似文献
997.
The cognitive neuropsychology proposes models to explore schizophrenics symptoms. The concept of theory of mind appeared in psychiatry fifteen years ago and is now a focus of research. Various comprehensive models of schizophrenia involving theory of mind have been proposed and explored by experimental tasks. Those models are useful to understand schizophrenic semiology and to explore brain by functional imaging. A review of these research is useful to understand their interest. 相似文献
998.
The impact of regular ecstasy use on memory function 总被引:1,自引:0,他引:1
Aim To assess memory impairment in a group of regular users of ecstasy compared with a group of regular users of cannabis, after accounting for possible confounding factors such as other drug use, premorbid intelligence and psychopathology.
METHOD Comparative and regression analysis was used to determine the presence or absence of a difference in memory function between 40 regular ecstasy users and 37 regular users of cannabis, who were interviewed at the National Drug and Alcohol Research Centre in Sydney, Australia. Regression analysis was used to find associations between life-time exposure to ecstasy use and memory performance. Memory function was assessed using an age-standardized memory test. Other scales were used to assess premorbid intelligence, physical and psychological health, drug withdrawal and other drug use.
Results Initial comparative analysis showed a trend towards a significantly poorer performance by the regular ecstasy-using group on the 'auditory immediate memory' and 'auditory delayed memory' indices. When regression analysis was performed an estimate of verbal intelligence was found to be the most predictive of most memory indices including 'auditory immediate memory' and 'auditory delayed memory'. Life-time exposure to ecstasy was not predictive of the memory indices. The current frequency of cannabis use was found to have some predictive effect for immediate and delayed visual memory.
Conclusion This study does not show memory impairment in a group of ecstasy users relative to cannabis using controls. The previously reported association of life-time exposure to ecstasy and memory was not found. The findings may indicate a confounding role of cannabis use, as has been recently reported. 相似文献
METHOD Comparative and regression analysis was used to determine the presence or absence of a difference in memory function between 40 regular ecstasy users and 37 regular users of cannabis, who were interviewed at the National Drug and Alcohol Research Centre in Sydney, Australia. Regression analysis was used to find associations between life-time exposure to ecstasy use and memory performance. Memory function was assessed using an age-standardized memory test. Other scales were used to assess premorbid intelligence, physical and psychological health, drug withdrawal and other drug use.
Results Initial comparative analysis showed a trend towards a significantly poorer performance by the regular ecstasy-using group on the 'auditory immediate memory' and 'auditory delayed memory' indices. When regression analysis was performed an estimate of verbal intelligence was found to be the most predictive of most memory indices including 'auditory immediate memory' and 'auditory delayed memory'. Life-time exposure to ecstasy was not predictive of the memory indices. The current frequency of cannabis use was found to have some predictive effect for immediate and delayed visual memory.
Conclusion This study does not show memory impairment in a group of ecstasy users relative to cannabis using controls. The previously reported association of life-time exposure to ecstasy and memory was not found. The findings may indicate a confounding role of cannabis use, as has been recently reported. 相似文献
999.
Heim C Sova L Kurz T Kolasiewicz W Schwegler H Sontag KH 《Journal of neural transmission (Vienna, Austria : 1996)》2002,109(5-6):691-709
Summary. To test substances which might have protective effects on the dopaminergic system it is necessary to use models with a pathological
symptomatology of the early beginning, i.e. models in which the chance exists to arrest the otherwise progressive pathological
processes (see Heim et al., 2001). 6-hydroxydopamine (6-OHDA) injected unilaterally into the ventrolateral striatum of rats
(6 μg dissolved in 2 μl 0.2% ascorbic acid) leads to specific stereotyped movements after subcutaneous injection of apomor-phine
both 3 and 13 weeks after surgery. Ten weeks after surgery decreased spontaneous motor activity could be observed. Twelve
weeks after 6-hydroxydopamine injection, the animals had difficulties in performing a spatial navigation task when the submerged
escape platform was moved to another position. The switching of motor programs was less pronounced. The application of tyrosine-hydroxylase-staining
showed a loss of ipsilateral neurones of the substantia nigra compacta as well as of dendrites in the pars reticulata, neurones
in the ventral tegmental area and in the retrorubral area ipsilaterally as well as a loss of dopaminergic fibres both ipsilaterally
and contralaterally in the striatum which should belong to the contralateral acting substantia nigra afferents. The loss of
the neurones and the afferents was induced by the retrograde denervation following the 6-OHDA injection within the ventrolateral
striatum. The question arises whether the model used here with the partially loss of dopaminergic neurons and fibres reflects
some of pathological symptoms of Parkinson's disease in the early states.
Received December 21, 2001; accepted February 25, 2002 相似文献
1000.
焦虑症的事件相关电位P300实验研究 总被引:2,自引:0,他引:2
目的观察焦虑症(AD)听觉事件相关电位P300的变化特点。方法对30例AD患者和30名健康成年人(NC组),应用脑诱发电位仪进行P300检测。结果与NC组相比,AD组Pz点P3潜伏期后移,NC组为(326±16)ms,AD组为(339±19)ms(P<0.01);P3波幅降低,NC组为(6.0±1.9)μV,AD组为(4.5±2.2)μV(P<0.05);非靶P2波幅降低,NC组为(3.8±0.9)μV,AD组为(1.7±0.8)μV(P<0.01)。结论AD患者P300变化诸特点值得进一步随访。 相似文献