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911.
The role of the vocal channel of emotion expression in infancy has been neglected in developmental theory. The present review describes the ontogenetic course of vocal emotional expression as exhibited by human and infrahuman primate young and considers its dynamic relationship to the facial and bodily components of expression. The infant's encoding of negative and positive emotion expression is discussed within a developmental framework. In addition, this review assesses the impact of early social influences. It is concluded that early patterns of infant vocal emotional expression are probably biogenetically determined and that there may be certain universal vocal signals. However, data derived from studies of dyadic interaction indicate that the transition from raw affect expression in early infancy to a more modulated pattern later on is a product not only of neuromuscular maturation but of maternal coaching in affective expression as well.  相似文献   
912.
Previous work has shown that adults and older children tend to classify multi-dimensional objects by identity on one dimension, whereas children under 8 years of age tend to classify these same objects by a relation of overall similarity. The present study investigated the hypothesis that this developmental trend is restricted to the classification of simple objects that differ only by limited amounts on a few dimensions. The specific hypothesis was that overall-similarity relations structure both adults' and children's classifications of heterogenous objects (objects that differ in a variety of ways). This hypothesis was suggested by the correspondence between the structure of young children's classifications and the structure of natural categories. The result of two experiments supported the hypothesis. When the to-be-classified objects varied simultaneously on relatively many dimensions, adults as well as children constructed classifications that maximized within-category similarity on all varying dimensions. The implications of these results for accounts of the perception of multidimensional relations and classificatory behavior are discussed.  相似文献   
913.
Medication effects in the classroom: Three naturalistic indicators   总被引:2,自引:0,他引:2  
Hyperactive and comparison boys participated in 5-week summer enrichment programs that included classroom activities and structured assessments of peer interaction patterns. During the 3rd and 4th weeks of these programs, a double-blind, methylphenidate-placebo crossover design was implemented within the hyperactive group. Three heterogeneous indicators of everyday behaviors were obtained: number of negative incidents noted by staff, quality of handwriting, and number of times the teacher called the boys' names aloud in the classroom. Medication effects emerged for each of these indicators. When hyperactive boys were taking placebos, they were involved in more negative incidents, their handwriting was poorer, and their names were called more frequently than when the boys were taking methylphenidate. Interrelationships among the measures suggest moderate cross-situational generality of medication responsiveness. Discussion focused on the bandwidth of medication effects and the need to examine the social ramifications of child treatments.This research was supported in part by NIMH grant 29475 and NIDA grant 01070. We gratefully acknowledge the participation of the data coders and the many summer school staff. Special thanks go to Mike Berlin, Barry E. Collins, and Sharon Dotemoto. Methylphenidate and placebo were supplied by Ciba-Geigy, Summit, New Jersey.  相似文献   
914.
The effects of valence of alternatives, choice, and expected delay of choice consequences on postdecision evaluations of choice alternatives were studied by either giving subjects a choice between two experimental tasks (both either pleasant or unpleasant) or assigning subjects their initially preferred task. Crosscutting valence and choice, subjects expected either no delay, 10-min delay, or 30-min delay before engaging in the task. All subjects evaluated both tasks immediately after the delay instructions but before experiencing the actual delay. Results confirmed the expected dissonance effect; that is, an upward evaluation of the chosen alternative and a downward evaluation of the rejected alternative, relative to no-choice conditions. Moreover, the relative upward evaluation of the chosen alternative increased as the expected delay decreased. Valence was not found to interact with other variables. The results are discussed in terms of differential salience of choice alternatives.  相似文献   
915.
The present study examined differences in pelvic vasocongestion as a function of negative attitudes toward masturbation. Pelvic vasocongestion was measured thermographically, which is a noninvasive means of detecting and photographing individual heat patterns to indicate physiological condition and functional changes within. The results indicated that women, with positive attitudes toward masturbation, who read an erotic story, experienced the greatest increase in pelvic vasocongestion. This and other findings were discussed in terms of masturbation acting to facilitate the patterning of sexual arousal and orgasmic functioning, especially in regard to creating the capacity for pelvic engorgement.  相似文献   
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Simple motor reaction times (right-handed) to tape-recorded consonant-vowel syllables were obtained from 12 subjects under two conditions of monotic stimulation: “expected” presentation (subject informed as to ear of presentation) and “random” presentation (ear of presentation varied randomly). Significantly faster left ear reaction times were obtained in the “expected” condition. The rank order of subjects' standard dichotic listening task scores correlated negatively with reaction time ear differences in the “expected” presentation condition. Results are discussed in terms of existing theories of response lateralization in simple reaction time tasks, and an expanded hypothesis is offered. Specifically, it is suggested that two or more distinct but potentially overlapping mechanisms may be responsible for observed asymmetries in monotic auditory perception. Both an attentional or lateralized motor response bias and an inherent lateralization of function may operate side by side, differentially activated by task demands, mode of stimulus presentation, and nature of stimuli.  相似文献   
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