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921.
Responding under positive and negative response contingencies in pigeons and crows 总被引:1,自引:1,他引:0 下载免费PDF全文
Four crows were trained to key peck for food. Then, they were exposed to a positive response contingency that required them to peck the key when it was illuminated briefly (the trial) in order to receive food. This procedure resulted in consistent within-trial pecking. When the contingency changed so that food was presented at the end of a trial when no response occurred, but the trial terminated immediately and food was omitted when a response occurred (negative response contingency), responding decreased markedly. Eight pigeons were studied under the same change in contingencies. These birds varied in their response histories from naive to having several years' experience. The previously naive pigeons also showed rapid declines in responding under the negative contingency; the responding of the birds with extended training histories declined much more slowly. Eventually, however, six of the eight pigeons showed little or no responding under the negative contingency, while they responded consistently when re-exposed to the positive contingency. These findings question the power and the generality of the negative automaintenance phenomenon. 相似文献
922.
Sentences containing self-embedded relative clauses are generally believed to be difficult to understand because such clauses interrupt the clauses in which they are embedded. However, the experiments that purport to have demonstrated this have confounded the self-embedded or fight-branching location of the relative clauses with their internal structure, comparing self-embedded object relatives with right-branching subject relatives. In order to break this confounding, Experiment I compared the comprehension difficulty of self-embedded and right-branching object relative clauses on two measures of comprehension difficulty. Experiment II made the same self-embedded vs. fight-branching comparison for subject relative clauses. The results of both experiments consistently failed to support the interruption hypothesis. 相似文献
923.
924.
Edward A. Wasserman James D. Deich Norman B. Hunter Linda S. Nagamatsu 《Learning and motivation》1977,8(4):467-487
A series of five experiments using a total of 264 subjects investigated the effects of paired and unpaired key light (CS) and heat (US) stimuli on autoshaping the chick's key peck. Experiment 1 established that paired presentations of CS and US promoted a more rapid rise in key pecking than did randomly presented CSs and USs and that the specific sequence of stimuli under the random control procedure affected key pecking performance. Experiment 2 used a trace conditioning procedure to determine the role of the CS-US interval on autoshaping and to define empirically unpaired CSs and USs. Key pecking declined as the trace delay interval was increased from 0 to 25 sec; at 25 sec, no conditioning of key pecking occurred. Experiments 3–5 assessed the effects on autoshaped key pecking of (a) number of daily CS-US pairings, (b) added unpaired CS presentations, and (c) added unpaired US presentations, since paired and random control schedules differed in all of these respects. Reduction in the number of CS-US pairings slowed the acquisition of key pecking as did the concurrent addition of nonreinforced CSs and unsignaled USs. These results support theories of association formation that stress the effects of both paired and unpaired CSs and USs. 相似文献
925.
926.
Robert W. Powell 《Journal of the experimental analysis of behavior》1971,16(1):95-104
Discriminative responding in pigeons was studied under multiple variable-interval extinction and variable-ratio extinction schedules, as deprivation was varied. Generally, the greater the accuracy of discrimination that developed during training, the smaller the effect of deprivation upon subsequent performance. This was true both in terms of changes in response rates, and in the relationship between response rates during food reinforcement and extinction. When discrimination was inaccurate, increases in deprivation resulted in disproportionate increases in responding during extinction, as compared to increases during food reinforcement components of the schedule. The results suggest that as stimulus control (accuracy) of responding increases, discriminative performance becomes less and less susceptible to influence by deprivation. 相似文献
927.
928.
M. Louise Clark J. Allan Cheyne Charles E. Cunningham Linda S. Siegel 《Journal of abnormal child psychology》1988,16(1):1-15
A sequential observational approach was used to compare peer interactions in 10 mixed dyads of ADD-H and non-Add-H boys and 10 dyads of non-ADD-H boys in laboratory cooperative and school classroom task analogue activities. Mixed dyads were found to have a greater frequency of aggression and less joint activity than control dyads in specific situations. No differences were found for measures of functional attention as measured by frequency, duration, and mean duration of task-oriented behavior. Lag sequential analyses revealed two major sequences that differentiated mixed from normal dyads. These were Verbal Reciprocity (a measure of reciprocal verbal interaction) and Retreat (a measure of social withdrawal following aggression). 相似文献
929.
Marital conflict,parenting, and toddler conduct problems 总被引:3,自引:0,他引:3
Ernest N. Jouriles Linda J. Pfiffner Susan G. O'Leary 《Journal of abnormal child psychology》1988,16(2):197-206
The present research examined relationships involving marital conflict, parenting, and toddler conduct problems. Sixty mother-toddler dyads (30 boys and 30 girls) participated as subjects. Mothers completed measures of general marital satisfaction, overt marital conflict, and toddler conduct problems. Maternal parenting and toddler deviance were assessed during a laboratory observation. Marital conflict was positively correlated with observations of toddler deviance and maternal reports of conduct problems. Marital conflict also correlated positively with the frequency of maternal disapproval statements directed toward sons' misbehaviors and was correlated negatively with the ratio of disapproval statements to daughters' misbehaviors. The present results indicate that marital conflict is associated with toddler conduct problems. The results also suggest the importance of examining parenting practices and child characteristics that may mediate the relationship between marital conflict and child behavior problems.This research was supported, in part by a Sigma XI grant to the second author. 相似文献
930.
Thirty male and 58 female students responded to questionnaires based on a 9-month period in a prospective study of the impact of hardiness, life events, and hassles on reports of somatic symptoms. The data were analyzed utilizing cross-lagged panel analyses, analyses of variance, and multiple regression analyses. The results suggested that life events, hassles, and symptoms were significantly related in a recursive, mutually interactive manner. Although life events shared a high degree of variance with hassles, hassles consistently contributed above and beyond life events in predicting somatic symptoms. In addition, hardiness tended to have additive and opposite effects to that of stressors in its impact on symptomatology. Finally, and perhaps most important, compared to lower-hardy individuals, those higher in hardiness tended to experience less frequent stressors and to perceive the minor events they did experience as less stressful. 相似文献