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831.
This study examines the effect of different behavioral conditions on patterns of correlation between regional cerebral metabolic rates for glucose. Cerebral glucose metabolism was determined with positron emission tomography and (11C)-deoxyglucose in 29 normal subjects between the ages of 23 and 55. Seventeen subjects were studied in an unstimulated (resting) condition and 12 subjects during a phoneme monitoring language stimulation. Partial correlation coefficients, controlling for whole brain glucose metabolism, were calculated for pairs of metabolic rates in 14 cortical and 2 subcortical regions. Both stimulated and unstimulated subjects showed statistically significant correlations between left and right hemisphere homologs. The stimulated subjects also showed significant within-hemisphere correlations between left but not right hemisphere regions. These included left perisylvian regions classically associated with language functions (left inferior frontal, left superior temporal and left transverse temporal cortical regions) as well as other regions. Significant correlations between left regions and a right superior temporal region were also found. In general, these findings show a pattern of cross-hemisphere symmetry at rest and of hemisphere asymmetry during stimulation. Moreover, the asymmetry observed during stimulation appears to be superimposed upon a pattern of cross-hemisphere symmetry similar to that observed in the unstimulated state. 相似文献
832.
833.
Two left-handed siblings with developmental stuttering are comprehensively described. The methods of study included speech and language evaluation, neurological and neuropsychological examinations, dichotic listening, auditory evoked responses, electroencephalogram, and CT scan asymmetry measurements. The data from each sibling showed evidence of anomalous cerebral dominance on many of the variables investigated. The CT scan measurements showed atypical asymmetries, especially in the occipital regions. These findings support the theory that stuttering may be related to anomalous cerebral dominance, both on functional as well as structural bases. Implications of anomalous dominance and the resultant effect of hemispheric rivalry on speech fluency are discussed. 相似文献
834.
Leonard A. Jason Charles L. Gruder Steven Martino Brian R. Flay Richard Warnecke Nathaniel Thomas 《American journal of community psychology》1987,15(1):57-72
At the work site, smoking accounts for increased health care expenses and worker absenteeism due to smoking-related illness and reduced productivity and lost wages. Developing comprehensive and accessible smoking cessation programs at the work site is an important objective for health care professionals. In this study, employees of 43 corporations participated in a televised smoking cessation program accompanied by self-help manuals. The media component involved presenting a smoking cessation program on a network television affiliate station during the 4:30 p.m. and 10:00 p.m. news for 20 days. Employees at half the corporations also had access to semiweekly self-help group meetings. Adding self-help support groups to a program involving self-help manuals and the media reports was found to significantly increase abstinence and its maintenance over time. The implications of using the media, self-help groups, and work site locations in large-scale community-based interventions are discussed. 相似文献
835.
Gary W. Evans Stephen V. Jacobs David Dooley Ralph Catalano 《American journal of community psychology》1987,15(1):23-34
One of the possible adaptive costs of coping with stress is diminished capacity to respond to subsequent adaptive demands. This paper examined the complex interplay between major life events and one source of chronic strain. Residents of the greater Los Angeles metropolitan area exposed to higher levels of smog, who had also experienced a recent stressful life event, exhibited poorer mental health than those exposed to pollution who had not experienced a recent stressful life event. There were, however, no direct effects of smog levels on mental health. These patterns of results were replicated in both a cross-sectional and a longitudinal study. The interplay of psychosocial vulnerability and environmental conditions is discussed. 相似文献
836.
837.
Vladimir A. Smirnov 《Studia Logica》1987,46(1):1-15
There is given the proof of strict embedding of Leniewski's elementary ontology into monadic second-order calculus of predicates providing a formalization of the class of all formulas valid in all domains (including the empty one). The elementary ontology with the axiom S (S S) is strictly embeddable into monadic second-order calculus of predicates which provides a formalization of the classes of all formulas valid in all non-empty domains. 相似文献
838.
David K. Henderson 《Synthese》1987,73(2):225-252
Common formulations of the principle of charity in translation seem to undermine attributions of irrationality in social scientific accounts that are otherwise unexceptionable. This I call the problem of irrationality. Here I resolve the problem of irrationality by developing two complementary views of the principle of charity. First, I develop the view (ill-developed in the literature at present) that the principle of charity is preparatory, being needed in the construction of provisional first-approximation translation manuals. These serve as the basis for explanatory accounts and associated refinements in the translation manual. In developing such explanatory accounts, the principle of charity is no longer constraining. Thus, the principle of charity applies only in the early stages of constructing translation manuals, and there is no problem of irrationality in the later stages of constructing translation manuals. Second, I reduce the principle of charity, where it does apply, to a special case of what I call the principle of explicability: so translate as to attribute explicable beliefs and practices to the speakers of the source-language. I show that the appropriate formulation of the principle of charity counsels just what the principle of explicability requires in the early stages of social scientific investigation.I am grateful to Robert Barrett, Roger Gibson, and Paul Roth for their generous assistance. 相似文献
839.
This study assessed the construct validity of the Revised Behavior Problem Checklist (RBPC) by measuring attention, autonomie arousal, and personality in 40 behaviorally disordered children aged 7 to 15 years. Conduct Disorder and Socialized Aggression subscales were characterized by high Psychoticism, Impulsivity, and Lie personality scores, by lower heart rate levels, and by more errors on a continuous performance reaction-time task. Conversely, Attention Problems, Anxiety Withdrawal, and Motor Excess were characterized by greater variability in reaction times. Conduct Disorder alone was related to an external locus of control, while only Attention Problems was characterized by low scores on the WISC Freedom from Distraction factor. These differential relationships suggest (a) support for the construct validity of the RBPC, (b) that antisocial behavior and hyperactivity/attention deficits are dissociated disorders, and (c) that hyperactivity/attention deficits may be characterized by fluctuations in the allocation of attentional resources rather than a core structural deficit in attention. 相似文献
840.
Intuition in insight and noninsight problem solving 总被引:9,自引:0,他引:9
People’s metacognitions, both before and during problem solving, may be of importance in motivating and guiding problem-solving behavior. These metacognitions could also be diagnostic for distinguishing among different classes of problems, each perhaps controlled by different cognitive processes. In the present experiments, intuitions on classic insight problems were compared with those on noninsight and algebra problems. The findings were as follows: (1) subjective feeling of knowing predicted performance on algebra problems but not on insight problems; (2) subjects’ expectations of performance greatly exceeded their actual performance, especially on insight problems; (3) normative predictions provided a better estimate of individual performance than did subjects’ own predictions, especially on the insight problems; and, most importantly, (4) the patterns-of-warmth ratings, which reflect subjects’ feelings of approaching solution, differed for insight and noninsight problems. Algebra problems and noninsight problems showed a more incremental pattern over the course of solving than did insight problems. In general, then, the data indicated that noninsight problems were open to accurate predictions of performance, whereas insight problems were opaque to such predictions. Also, the phenomenology of insight-problem solution was characterized by a sudden, unforeseen flash of illumination. We propose that the difference in phenomenology accompanying insight and noninsight problem solving, as empirically demonstrated here, be used to define insight. 相似文献