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961.
The effect of a fading procedure upon the acquisition of control by an overshadowed auditory feature 下载免费PDF全文
Pigeons' key-pecking responses were reinforced in the presence of a compound stimulus that consisted of an auditory feature (a tone) and a visual feature (a light) and non-reinforced in the presence of a compound stimulus that was either a noise and a dark key, or noise and a light. In the condition where reinforcement trials differed from non-reinforcement trials on the basis of both auditory and visual features, the tone exerted very little control over responding on test. In the condition where reinforcement differed from non-reinforcement trials solely on the basis of the auditory features, an abrupt and a gradual introduction of the visual feature of the negative stimulus, a light, were compared for their effect upon control in the compounds. The tone acquired strong control in both cases. Evidence indicated that the tone had acquired control in the gradual condition without the occurrence of responses to the negative stimulus. An incidental finding was that when the negative stimulus consisted of a noise and a light, which was introduced abruptly, responding over the light dimension with tone, on test, was peaked at a point other than that light value used as positive and negative during training. 相似文献
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For a joint family story-telling task, families with a schizophrenic offspring were compared to normal families on the completeness and clarity of the final composite stories and on their interactional behavior. The composite stories from schizogenic families were more “vague and confused”, fragmented, and less complete as to the five components required to satisfy the task instructions. Schizogenic families displayed more conflict, failure, and confusion during the interactional task than control families, and, fathers and mothers of schizophrenic offspring displayed more “anxiety and tension”, “depressive mood”, “evasiveness” and “lack of interest” than fathers and mothers of normal families. Mothers of schizophrenic offspring were also described as more “hostile” than control mothers. Comparing schizogenic families from which the patient was absent during the task with schizogenic families with the patient present, and with control families, indicated that the central findings were not attributable to the immediate presence and participation of the schizophrenic member. 相似文献