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781.
Twenty treated and 18 untreated spider phobics were exposed to a series of 72 slides. Three different categories of slides were used: phobia-relevant slides (spiders), alternative fear-relevant slides (weapons), and neutral slides (flowers). Slides were randomly paired with either a shock, a tone, or nothing at all. Despite the absence of a systematic correlation between slides and outcomes, untreated phobics strongly overestimated the covariation between spider slides and shock. Treated phobics did not show a covariation bias, suggesting that such bias can be modulated by behavioral treatment. In addition, untreated subjects were more confident about their contingency estimates than were treated subjects. The present results fit with earlier studies. 相似文献
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786.
Event-related potentials (ERPs), accuracy scores, and reaction times were used to examine the recognition of emotional expressions. Adults and 7-year-old children saw upright and inverted chromatic slides of the facial expressions of happiness, fear, surprise, and anger, and were asked to press a button for either "happy" or "angry" faces. A positive-going waveform (P300) was apparent at parietal scalp (Pz) and at left and right temporal scalp. Although the behavioral data were similar for both children and adults (e.g., both had more difficulty recognizing angry expressions than happy ones, and angry expressions were more difficult to recognize upside-down than were happy faces), the ERPs indicated that children responded differently than adults did to happy and angry expressions. Adults showed greater P300 amplitude to happy faces, while children showed greater P300 amplitude to angry faces. In addition, for adults, but not children, there were greater P300 amplitude responses at right vs. left temporal scalp. 相似文献
787.
Light and Humphreys (1981, Journal of Experimental Child Psychology, 31, 521-530) provided evidence that young children's drawings, despite infrequently showing view-specific occlusion, do systematically reflect spatial relations within an array. The present research tested the hypothesis that young children's preferences for canonical "best views" interact with array-faithful tendencies to increase early uses of occlusion. Forty-three children between 4 and 7 years of age drew arrays like Light and Humphreys' end-to-end alignments, with end-on views of objects in depth, and arrays aligned side-to-side, with canonical side-views of objects in depth. Significantly fewer single-object, view-specific occlusions were produced for end-to-end than for side-to-side alignments. Nevertheless, the former reveal that more children are able to use the vertical dimension to depict multiple objects in depth. Other comparisons suggest an interaction in multiple-object depictions of canonicality with spatial dimension and graphic complexity. 相似文献
788.
Three mirror tracing experiments were conducted to investigate the connection between perception and motor behavior. In the first experiment, some subjects traced a hex-maze, other subjects traced a hex-maze after observing a model trace, others traced a hex-maze after reading instructions on mirror images, and others traced a hex-maze after having observed a model and heard the instructions. There were no significant differences between the groups' error scores, but their time scores differed significantly, although not always in the predicted direction. In Experiment 2, the subjects were to trace selected letters of the alphabet. Error scores for the second experiment did not differ much from those for the first experiment. In Experiment 3, the experimenter gave each subject commands for the correct directions of movement, using the subject's body as a frame-of-reference. There was little improvement in motor performance. These results suggest that the visual information presented in the mirror captured the subjects' attention and blocked their motor tracing program. 相似文献
789.
Exposed eye area (EEA) was measured in photographs of Indian adults who modeled six emotions--happiness, sadness, fear, anger, surprise, and disgust--as well as a neutral expression. The data were analyzed with a 2 x 6 (Eyes x Emotions) factorial analysis of covariance (ANCOVA). EEA for neutral expression was used as the covariate measure. The EEAs of the two eyes did not differ significantly during the expression of emotion. The EEAs for fear and surprise were significantly larger, and the EEA for disgust was significantly smaller than those for either other emotions or neutral expression. 相似文献
790.
In this study 21 displaced workers were interviewed regarding factors affecting their participation in training programs funded by the Job Training Partnership Act. Differences between program participants and nonparticipants, differences among program participants, and differences among nonparticipants were identified. 相似文献