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A free-operant avoidance schedule was used to establish and maintain foot-treadle responding by two Homing, one White King, and two Carneaux pigeons. In the absence of responding, the interval between shocks equaled 10 sec. Each time a treadle response occurred the shock was postponed for 32 sec. Pigeons appear to learn the treadle response more quickly and use it to avoid shock more successfully than do rats bar pressing on similar schedules. The treadle response becomes highly stereotyped and interresponse time distributions obtained from terminal behavior appear very similar to data obtained from rats. It is concluded that the difficulty in training pigeons to avoid electric shock is not in establishing avoidance behavior but in attempting to evaluate such behavior with the key-peck response.  相似文献   
163.
Food-deprived pigeons responded under a 10-min fixed-interval schedule of food presentation. During even-numbered minutes of the schedule, the discriminative stimuli were the same as those present when food was delivered. During odd-numbered minutes there was either a change in keylight color or a change in overhead illumination, either for the entire duration of the odd-numbered minutes, or for 3-sec after each response. Responding during even-numbered minutes showed the usual pattern of positive acceleration; responding during odd-numbered minutes was similarly graded, but rates were much lower. The response-rate-increasing effects of amobarbital were inversely related to control rates of responding for both even- and odd-numbered minutes. However, when the stimulus change during odd-numbered minutes was either keylight color or a change from a darkened to a brightly illuminated chamber, increases in responding were considerably less than predicted on the basis of the effects on responding during even-numbered minutes. When the stimulus change was from a darkened to a dimly illuminated chamber, control rates of responding changed little, but increases in responding during odd-numbered minutes after amobarbital were considerably greater, and of the approximate order expected on the basis of control rate.  相似文献   
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The impact of professional negotiations on the current educational scene is examined and related to clarification of the school counselor role. Role confusion continues in the school situation, and negotiations may well be the way to bring about a change in the status quo. Negotiations for counselors are explored from the standpoints of dimensions of negotiations, implementation of negotiations, and attitude of professional associations. Conclusions are that negotiations have significant implications for counselor role delineation.  相似文献   
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The use of three electrodes to produce digitizable EKG’s and to deliver shocks to the tail of the monkey is described. Cardiac signals are taken from a head electrode and a “ground” tail electrode. Shock is administered through a “hot” tail electrode and the “ground” tail electrode.  相似文献   
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