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881.
Pigeons' responses were reinforced on a variant of a mixed variable-interval extinction schedule of reinforcement in which the transition to the higher reinforcement rate was signaled by a trace stimulus projected on the response key prior to the onset of the component correlated with food delivery. In the first of two experiments, the duration of the trace stimulus preceding the component correlated with food delivery was varied from 1.5 to 50.0 s and in the second experiment, the reinforcement frequency in the same component was varied from 10 to 60 reinforcers per hour. Pigeons pecked at the trace stimulus preceding the onset of the component correlated with food delivery even though responding was not reinforced in its presence and only one of the changes in reinforcement rate (i.e., from extinction to reinforcement) was signaled. The rate of pecking during the trace stimulus was a function of its duration but not of the reinforcement frequency in the following component. Higher rates generally occurred at the shorter trace-stimulus durations. Component responding following the offset of the trace stimulus was under discriminative control of the trace stimulus whether or not responding occurred in the presence of the trace stimulus. 相似文献
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Little is known about the personal life of John B. Watson, and this interview aims at capturing the personality of the founder of American behaviorism through the eyes of his son, James B. Watson. Today, psychologists and other social scientists increasingly realize that there is an intimate link between the biography of a psychologist and the kind of psychology he or she founds. Thus biographical information about a founding psychologist can help researchers make explicit this essential link. 相似文献
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Some experiments on the breakdown effect in apparent motion 总被引:2,自引:0,他引:2
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Glynis M. Breakwell 《British Journal of Guidance & Counselling》1987,15(3):285-296
All higher and further education institutions who reported having a student counselling service were surveyed, using a postal questionnaire, during 1985. Information from 212 institutions is presented. It describes what services exist, how long they have existed, their staffing and their workload (in terms of numbers counselled and type of service offered). Comparisons between universities, polytechnics and colleges of higher and further education are made. The stated objectives of the counselling services are summarised, together with identified priorities in counselling functions. Some of the characteristics of counsellors are outlined, including hours worked, training and qualifications. 相似文献