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181.
The internal structure of the Repression-Sensitization (R-S) Scale was examined by means of factor analysis. Following a scree
test, four factors were extracted: lassitude/depression, extraversion/confidence, guilelessness/trust, and emotional lability.
Concurrent validation using the Emotion Control Questionnaire and the Eysenck Personality Inventory showed that the factors
extracted from the R-S Scale were related in predictable ways to existing personality constructs, but the results argue against
the use of the overall R-S score as an index of emotional response style. 相似文献
182.
This study explores the relationship between media use and political commitment. Undergraduate participants answered an extensive
political background questionnaire, which included measures of media use, perceived importance of information sources regarding
the 1992 presidential election, and various political behaviors as an index of political commitment. Correlational analyses
revealed that those who are more politically committed tend to select a variety of media sources regarding a presidential
candidate. This study also investigated how informational and commitment variables were related to attitudes towards the major
presidential candidates. Results observed for people expressing positive attitudes toward Perot are discussed in terms of
the modern day “third party voter.” 相似文献
183.
184.
本工作采用食物性运动,条件反射方法和慢性微电极记录技术。条件反射实验在9只兔上进行,海马自发放电的实验在22只兔上进行。在9次实验中,30μg的东莨菪碱注入一侧脑室后,条件反射均受到抑制,而吃食则不受影响。注射剂量为45μg时,注射后3—5分,条件反射完全消失,而吃食行为在了次实验中不受影响,在2次实验中稍有减弱,注射后20分钟左右条件反射开始恢复;侧脑室注射40μg的东莨菪碱后,海马神经元的自发活动无明显改变。文中并对抗胆碱药作用于海马抑制条件反射的可能方式进行了讨论。 相似文献
185.
汉语语义记忆提取的初步研究 总被引:1,自引:0,他引:1
对汉语语义记忆的提取进行了两个实验。实验1是自由联想实验,从十三个句子中选出二十三个词作为刺激词。结果表明,以两词间所保持的常识关系来定义的语义距离,对预测自由联想的作业是有效的。实验2采用反应时技术,对真假命题判断及信息提取的时间进行了考查。实验结果与A.M.Collins等人的结果一致,说明了存储于网络不同水平上的句子其提取时间不同这一事实。结果还表明,在信息提取阶段上,汉字字形的作用不是一个重要的因素。 相似文献
186.
187.
Drug effects on responding maintained by stimulus-reinforcer and response-reinforcer contingencies. 下载免费PDF全文
R D Spealman J L Katz J M Witkin 《Journal of the experimental analysis of behavior》1978,30(2):187-196
The effects of pentobarbital and d-amphetamine were assessed on key pecking by pigeons under conventional single-key multiple schedules and under two-key multiple schedules in which discriminative stimuli appeared on one key (stimulus key) while pecks on a second key (constant key) produced food. Pecks on the stimulus key had no scheduled consequences. A 60-second variable-interval schedule operated in one component of each multiple schedule: either extinction or a 60-second variable-time schedule operated in the alternate component. When the alternate-component schedule was extinction, a high rate of responding was maintained in the variable-interval component of the single-key schedule; responding on both keys was maintained in the variable-interval component of the two-key schedule. Pentobarbital increased responding in the variable-interval component of the single-key schedule and increased stimulus-key, but not constant-key responding in that component of the two-key schedule. When the alternate-component schedule was changed to variable time, responding declined in the variable-interval component of the single-key schedule; stimulus-key responding was no longer maintained under the two-key schedule. Pentobarbital decreased responding in the variable-interval component of both schedules. With an exception, d-amphetamine only decreased responding in the variable-interval component of the single- and two-key schedules both when the alternate-component schedule was extinction and when it was variable time. The results suggest that the effects of pentobarbital, but not d-amphetamine, depend on the nature of the contingency (stimulus-reinforcer, response-reinforcer) that maintains responding. 相似文献
188.
189.
The performance of pigeons trained to detect differences in the duration of stimuli was analysed using a matching model of signal detection. Two white stimuli, S1 and S2, differing in duration, were arranged with equal probability on the center key of a three-key chamber. S1 was systematically varied from 5 seconds to 25 seconds while S2 remained constant at 30 seconds. On completion of the center-key stimulus, a peck on the center key turned on the two red side keys. A left-key response was "correct" when S1 had been in effect on the center key and a right-key response was "correct" on S2 trials. A correct response produced a 3-second magazine light accompanied intermittently by food. Incorrect responses produced 3-second blackouts. Detection performance was measured under two procedures. In the first, the obtained reinforcement ratio was uncontrolled by allowing the number of food reinforcements obtained for correct left- and right-key responses to vary as the stimuli were changed. In the second procedure, the presentation of food reinforcement was controlled by holding the obtained reinforcement ratio constant. Discriminability changed as a function of stimulus differences under both procedures. No such trend was found in response bias. 相似文献
190.
An investigation of peak shift and behavioral contrast for autoshaped and operant behavior. 总被引:1,自引:1,他引:0 下载免费PDF全文
Instrumental treadle press and nonreinforced key peck responses were monitored during discrimination training and generalization testing in pigeons on positive and negative reinforcement schedules. In Experiment 1, six pigeons pressed a treadle for food on a multiple variable-interval extinction schedule. In Experiment 2, three pigeons pressed a treadle to avoid shock on a multiple free-operant avoidance extinction schedule. Different color keylights signaled S+ and S- components. Some positive behavioral contrast occurred during discrimination training, but the effect was small. Pecking occurred to the S+ keylight in Experiment 1 but not in Experiment 2. On stimulus generalization tests, all subjects displayed a positive peak shift when pressing the treadle for food or to avoid shock. However, peak shift was not found for nonreinforced "autopecks" on the stimulus key, although an area shift was observed in Experiment 1. This is the first demonstration of peak shift for pigeons pressing treadles and the only reliable demonstration of peak shift when negative reinforcement maintained responding. These results, in combination with previous demonstrations of peak shift for rats pressing levers and pigeons pecking keys, indicate that peak shift is a general by-product of operant discrimination learning, since it occurs across a variety of the organisms, responses, and reinforcers. 相似文献