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101.
Rats obtained access to food twice each 24-hour period. The first session was a work session in which food was available on a progressive-ratio schedule. During the second session, which occurred between 1 and 23 hours after the work session, food was freely available up to a fixed total intake each 24 hours. The situation resembled elements of several real world circumstances, including the choice between continuing to forage in a rapidly depleting patch and waiting for a better patch, and between working now and receiving a guaranteed income later. The purpose of the experiment was to explore the time period over which future access to reward could affect current responding. Contrary to what might be expected from recent theorizing, anticipation of future food delayed by an hour or more after the start of the work session had no effect on current performance. Food intake was high and constant during work sessions except for a prefeeding effect that occurred when the free session closely preceded the next day's work session. Also, an increase in the difficulty of the work schedule increased the amount of work and the maximum price paid for food as if the work session were the only time food was available. The results indicate the importance of considering temporal limits in theories that require animals to integrate input over time to determine the allocation of resources among alternatives.  相似文献   
102.
Transfer of matching-to-figure samples in the pigeon   总被引:2,自引:1,他引:1       下载免费PDF全文
Three pigeons were trained on a modified six-key matching-to-sample procedure. The third peck on the figure-sample key (which presented a bird, hand, face, beetle, rabbit, fish, flower, or red hue, as the sample) lighted only one comparison key. Every three additional pecks on the sample lighted another comparison key, up to a maximum of five keys. Pecks on keys of matching figures produced grain. Pecks on nonmatching keys (mismatches) turned off all lights on the comparison keys and repeated the trial. Three figures were used during acquisition. The birds learned to peck each sample until the matching comparison stimulus appeared on one of three comparison stimulus keys, and then to peck that key. Later, five novel stimuli, employed as both sample and comparison stimuli, and two additional matching keys were added. Each bird showed matching transfer to the novel samples. The data suggest that the birds may have learned the concept of figure matching rather than a series of two-component chains or discrete five-key discriminations.  相似文献   
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Fear and courage     
S. Rachman   《Behavior Therapy》1984,15(1):109-120
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109.
Earlier work on the quality of care in settings for severely and profoundly mentally-handicapped adults raised the question whether any useful purpose is served by promoting the extensive use of simple recreational materials to occupy people. Data were collected by direct observation on the activity of 6 adults living in a staffed house organized to promote engagement in household activities. Observations were taken over 5 weekdays from 07.00 to 10.00 and 15.00 to 23.00hr. The results showed that Ss spent between 22 and 67% of available time in purposeful activity. Between 27 and 65% of purposeful activity was engagement in domestic or housework tasks. Even the most handicapped people spent more time engaged in housework than in leisure and recreational tasks. The implications of these data are commented on and measurement issues which arise in ordinary housing as opposed to institutional settings are discussed.  相似文献   
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