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261.
Cadets at the U.S. Military Academy completed a questionnaire describing their experiences in Cadet Basic Training (CBT) and Cadet Field Training (CFT). Analyses of variance examined the impact of Group Role (Leader vs. Follower) and Perceived Group Effectiveness (High vs. Low) on group member perceptions of the extent to which each of six factors affected group performance. Significant main effects for Perceived Effectiveness were interpreted in terms of the egodefensive bias. Role main effects indicated that leaders tended to make stronger dispositional attributions than did followers. There were no signifcant Group Role × Perceived Effectiveness interaction effects. Findings support, in part, hypotheses concerning the operation of an attributional bias within the leader-member relationship.  相似文献   
262.
Subjects in Santa Barbara, California, and Groningen, The Netherlands, participated in a seven-person social dilemma game, presented in terms of a conservation of resources problem. Prior to their decision making in the social dilemma game, subject's social motive (altruistic, cooperative, individualistic, competitive) was assessed by means of two different classification procedures. On the basis of previous research findings American subjects were expected to display relatively more competitive social motives, and Dutch subjects relatively more cooperative ones. However, no indications of crosscultural differences were found neither with regard to the distribution of social motives nor with regard to the amount of resources taken for self in the social dilemma game. In both locations, competitive subjects took most resources for self, individualistic subjects took next most, cooperative subjects took less than individualists, and altruistic subjects took the least. In addition to predictive validity, indices of the convergent validity of two social motive assessment procedures were described.  相似文献   
263.
Two experiments assessed the importance of sound duration for eliciting head orientation responses from newborn infants. In Experiment 1, thirty infants turned with equal frequency toward 20-s continuous rattle sounds and 20-s trains of rattle segments. The duration of the rattle segments--14 and 100 ms (2/s), or 500 ms (1/s)--did not influence the likelihood of turning. Response latencies and durations proved quite similar for all stimuli. In Experiment 2, twenty-four infants heard continuous rattle sounds of four different durations: 1, 5, 10, and 20 s. They turned reliably to all stimulus durations; furthermore, the magnitude and temporal characteristics of head orientation responses did not differ for the four stimulus durations. These results suggest that the newborn's head orientation response may reflect a motor program that is initiated by auditory input and then executed in a similar fashion regardless of further stimulation.  相似文献   
264.
Partial pictures depict only selected portions of prose passages. Partial pictures hypothetically aid retention by inducing young children to generate imagery for nonpictured prose. Results from two hundred eighty-eight 6-year-old children indicated that (a) partial pictures at study facilitate recall, (b) identical study and retrieval prompts facilitate recall, and (c) imagery instructions and training do not affect retention. Partial pictures apparently help children to encode information more efficiently at study, but there is no evidence that young children generate images with the aid of the partial picture cues, nor that they have a retrieval deficit for these images as suggested by M. Ruch and J. Levin.  相似文献   
265.
Estimates of the probability of various outcomes associated with treatment for kidney failure were made by chronic dialysis patients, dialysis patients awaiting transplant, successful transplant patients, and unsuccessful transplant patients back on dialysis. The latter two groups can be considered a natural experiment testing the impact of personal experience on population predictions. Consistent with the law of small numbers and the availability heuristic, successful transplant patients gave higher estimates of the population success rate for transplantation than unsuccessful transplant patients gave.  相似文献   
266.
267.
When discriminated interresponse-time (IRT) procedures have been used to assess preference relations among temporally extended operants, deviations from matching have been obtained. Using a yoked-control procedure, the present study found that key pecking in a discriminated IRT procedure has two sources of strength--that arising from the response-reinforcer contingency that is explicitly arranged, and that arising from a stimulus-reinforcer contingency that is a by-product of the explicitly arranged contingency. The key pecking of all lead birds, and that of 3 of the 4 birds exposed to a yoked autoshaping procedure, was controlled by the keylight that signaled the lead birds' criterion IRTs. Because stimulus control of key pecking by the keylight, whether autoshaped or discriminative, fosters deviations from matching, the discriminated IRT procedure does not provide an appropriate basis for conclusions about preference relations among IRTs.  相似文献   
268.
The present experiment used hippocampal stimulation to determine the temporal gradient of consolidation of spatial working memory. Rats were trained to perform a spatial working memory task on a radial maze with 12 arms. Each rat went to the ends of 6 arms to obtain a food reward. After 8 h, the rat chose among all the arms to find the ones not previously chosen (and consequently still having food). During some test sessions, the hippocampus was stimulated electrically either at a current level just high enough to produce an electrophysiological seizure, or at a current level below this seizure threshold. Stimulation occurred at one of five intervals (0 to 8 h) following the completion of the first six choices. During other test sessions, the hippocampus was not stimulated. After seizure stimulation, the number of retroactive errors (returning to arms chosen prior to stimulation) increased at all delay intervals; the number of proactive errors (returning to arms chosen after stimulation) increased only with the delay of 8 h. Subthreshold stimulation had no influence on either type of error. These results indicate that normal hippocampal function is required for the maintenance of spatial information in working memory, and that the time course of consolidation of this information is significantly greater than that seen in other types of memory, or consolidation may not take place at all.  相似文献   
269.
Some effects of color on naming and recognition of objects   总被引:1,自引:0,他引:1  
In this article, we investigated the role of color in the recognition and naming of everyday objects. In the first experiment we found that color pictures were named faster than black-and-white and that shape information did not facilitate color naming. Experiment 2 was carried out to determine at which stage of object processing the color facilitation occurred. We found that color had no effect on object recognition but did facilitate object naming, even when color was redundant for discrimination. This did not apply to naming abstract shapes. Experiment 3 replicated the findings of Experiment 2 using different objects and colors. The results showed that color could facilitate but not inhibit object naming and did not affect object recognition.  相似文献   
270.
This study describes the development of the Attitudes Toward Women Scale for Adolescents (AWSA), an instrument based on the short form of the Spence-Helmreich Attitudes Toward Women Scale (AWS). The AWSA has been tested in four samples of adolescents. Internal consistency estimates and test-retest stability indicated high reliability. Hypotheses formulated to test the construct validity of the scale were largely supported. AWSA permits the examination of how boys' and girls' attitudes toward women influence the life paths that adolescent girls begin to pursue.This research was supported by grants to A. Petersen from the Spencer Foundation, the National Institute of Mental health (MH 30252/38142), and the Judith Baskin Offer Fund.  相似文献   
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