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911.
This study researches the input of the cerebral occipital and temporal cortex in the analysis of facial configuration and expressive characteristics. Analysis is based on the construction of a spherical model for the differentiation of schematically presented faces with quantitatively altering curvature of the mouth and brows. The model is designed using the method of multidimensional scaling of the dissimilarity judgments between stimuli (faces) and the amplitude of evoked potentials of differences (EPD) between abrupt stimulus changes recorded from the occipital and posterior temporal cortex. Analysis of the structure of the spherical model of facial differentiation depending on the electrode site and the latency of the EPD component within the duration of 120-240 ms has demonstrated that the activity of the occipital and posterior temporal cortex of the right hemisphere is associated with the emotional characteristics of the presented face, whereas facial configuration is reflected in the activation of both posterior temporal cortex and the occipital cortex of the left hemisphere. At all electrode sites maximum information of the emotional expression and configuration is represented in inter-peak amplitude P120-N180. With increasing latency there is increased distortion of the structure of differences in the spherical model of schematically presented faces, which is interpreted as an attenuation of electrical activity associated with the analysis of the emotional expression, which occurs more rapidly than configuration analysis.  相似文献   
912.
Are abstract representations of number – representations that are independent of the particular type of entities that are enumerated – a product of human language or culture, or do they trace back to human infancy? To address this question, four experiments investigated whether human infants discriminate between sequences of actions (jumps of a puppet) on the basis of numerosity. At 6 months, infants successfully discriminated four‐ versus eight‐jump sequences, when the continuous variables of sequence duration, jump duration, jump rate, jump interval and duration, and extent of motion were controlled, and rhythm was eliminated. In contrast, infants failed to discriminate two‐ versus four‐jump sequences, suggesting that infants fail to form cardinal number representations of small numbers of actions. Infants also failed to discriminate between sequences of four versus six jumps at 6 months, and succeeded at 9 months, suggesting that infants’ number representations are imprecise and increase in precision with age. All of these findings agree with those of studies using visual–spatial arrays and auditory sequences, providing evidence that a single, abstract system of number representation is present and functional in infancy.  相似文献   
913.
This article presents a method for using Microsoft (MS) Excel for confirmatory factor analysis (CFA). CFA is often seen as an impenetrable technique, and thus, when it is taught, there is frequently little explanation of the mechanisms or underlying calculations. The aim of this article is to demonstrate that this is not the case; it is relatively straightforward to produce a spreadsheet in MS Excel that can carry out simple CFA. It is possible, with few or no programming skills, to effectively program a CFA analysis and, thus, to gain insight into the workings of the procedure.  相似文献   
914.
915.
Background: To introduce a person with multiple disabilities to a microswitch-aided program, one has to select a plausible response(s), that is, a response(s) that can be performed reliably and without excessive effort by the person and can successfully activate the microswitch(es) available (producing preferred stimuli). This paper provides an overview of the responses adopted for microswitch activation in research studies during the last 20 years. Method: Computerized and manual searches were carried out to identify the studies published between 1986 and 2005. Forty-eight research studies were identified. They concerned the use of (1) a single (typical) response, (2) a single (non-typical) response, (3) multiple (typical and non-typical) responses, and (4) multiple (vocal) responses. Results and discussion: The results showed that 151 of the 190 participants involved in the studies had a positive outcome (i.e., clear increases in their responding, which suggested that they had learned the association between responding and consequent preferred stimuli). Failures were largely concentrated in the first group of studies. The discussion focused on (a) the importance of selecting plausible responses for increasing the chances of success, (b) the need of non-typical responses for persons with minimal motor behavior, (c) implications of programs with multiple responses on engagement and choice, and (d) relevance of using vocal utterances. Some suggestions for future research concerning these points were also examined.  相似文献   
916.
Li Y  Hu X  Ma W  Wu J  Ma G 《Body image》2005,2(2):91-103
In order to investigate the body image self-perception and the prevalence of body dissatisfaction among Chinese children and adolescents, 9100 children aged 3-15 years living in four cities completed a questionnaire assessing body image self-percepts and ideals by figural stimuli. The results indicate that (1) children's body ratings started to be significantly related to their BMIs at age 5 and correlations increased with age; (2) a wide range of current body sizes was chosen by Chinese boys and girls; (3) the ideal body sizes of boys and girls selected by boys and girls, respectively, were "boys by boys">"boys by girls">"girls by boys">"girls by girls" and (4) the satisfaction, mild dissatisfaction, and moderate dissatisfaction rates were 40.1%, 36.4% and 23.5%, respectively. Differences as a function of gender and age were identified. It was concluded that the prevalence of body dissatisfaction among children and adolescents of urban China was striking, and that the Chinese boys were not immune to body dissatisfaction.  相似文献   
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918.
919.
920.
Two previous studies found that life stress and parental alcoholism were not as highly related to distress for Hispanic adolescents as they were for European American adolescents (M. Barrera Jr., S. A. Li, and L. Chassin, 1993, 1995). Those findings could be interpreted as evidence of Hispanic youths' resilience, but limitations of the stress measure and the homogeneity of the Hispanic sample threatened this interpretation. The present study improved on those previous studies by using a new measure of uncontrollable stressors and a more heterogeneous Mexican American sample. Participants in this study were 175 Mexican American and 59 European American adolescents and their parents. Unlike the previous studies, results did not show that Mexican American adolescents were more resilient to parental problem drinking or life stress than were European American adolescents. Overall, life stress was related to adolescents', mothers', and fathers' reports of adolescents' psychological distress above and beyond the effects of ethnicity and socioeconomic factors.  相似文献   
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