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Out-of-seat and talking-out behaviors were studied in a regular fourth-grade class that included several "problem children". After baseline rates of the inappropriate behaviors were obtained, the class was divided into two teams "to play a game". Each out-of-seat and talking-out response by an individual child resulted in a mark being placed on the chalkboard, which meant a possible loss of privileges by all members of the student's team. In this manner a contingency was arranged for the inappropriate behavior of each child while the consequence (possible loss of privileges) of the child's behavior was shared by all members of this team as a group. The privileges were events which are available in almost every classroom, such as extra recess, first to line up for lunch, time for special projects, stars and name tags, as well as winning the game. The individual contingencies for the group consequences were successfully applied first during math period and then during reading period. The experimental analysis involved elements of both reversal and multiple baseline designs. 相似文献
955.
A 16-yr-old retarded male, diagnosed organically blind and treated by those around him as a blind person, was given practice in discriminating visual stimuli. After training, he responded with significantly better than chance accuracy in a choice situation in which stimuli were as small as 18 pt Futura Medium type. In addition, he was trained to look at the experimenter's eyes when instructed to do so. Control procedures revealed that it was the reinforcement contingency that functioned to establish and maintain eye contact. Eye contact with the experimenter generalized in a limited way to situations in which this behavior was not reinforced, though not to a neutral individual. When the boy was required to use visual cues to help himself in a cafeteria line, he soon emitted the necessary behaviors, where formerly he had been assisted by others. Resumption of assistance markedly decreased self-help, suggesting that continued use of any newly learned skills would depend on the response of the individuals in his environment. The boy also learned eating behavior that appeared to require the use of visual cues. 相似文献
956.
957.
Effect of a placebo on a simple motor response 总被引:1,自引:0,他引:1
958.
When pigeons' standing on one or the other side of a chamber was reinforced on two concurrent variable-interval schedules, the ratio of time spent on the left to time spent on the right was directly proportional to the ratio of reinforcements produced by standing on the left to reinforcements produced by standing on the right. The constant of proportionality was less than unity for all pigeons, indicating a bias toward the right side of the chamber. The biased matching relation obtained here is comparable to the matching relation obtained with concurrent reinforcement of key pecks. The present results, together with related research, suggest that the ratio of time spent in two activities equals the ratio of the “values” of the activities. The value of an activity is the product of several parameters, such as rate and amount of reinforcement, contingent on that activity. 相似文献
959.
Davison MC 《Journal of the experimental analysis of behavior》1969,12(2):247-252
Pigeons were trained on a two-link concurrent chain schedule in which responses on two keys were reinforced according to independent variable-interval schedules by the production of a change in key color. Further responses on the key on which the stimulus change had been produced gave a single food reinforcement and a return to concurrent variable-interval conditions. On one key the terminal link was a two-valued mixed-interval schedule, while on the other, the terminal link was a fixed-interval schedule. When the mixed-interval values were kept constant and the fixed-interval values varied, relative response rates in the initial concurrent links matched relative reinforcement rates in the terminal links when these were computed from cubic transformations of the reciprocals of the intervals comprising the terminal link schedules. 相似文献
960.
Compared with the data of goldfish trained only with stimuli correlated with reinforcement, interspersed reinforcement-stimulus and extinction-stimulus trials resulted in sharper stimulus control and a marked reduction in the percentage of key-presses emitted in the presence of stimuli located near the extinction stimulus on the test dimension. If non-reinforced trials were not interspersed with reinforced trials, there was no sharpening of stimulus control and less reduction in key presses in the presence of stimuli near the extinction stimulus on the test dimension. 相似文献