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121.
Nondepressed human subjects were divided into seven groups. On a series of discrimination problems, a helplessness group received insoluble problems, a solvable group received contingent feedback, and a no treatment control group received no feedback. For two other groups insoluble problems were preceded by success feedback on a different task presented according to a fixed ratio (FR) or variable ratio (VR) schedule of reinforcement. Two control groups received either FR or VR schedules of success but were not examined on the discrimination problems. All groups were tested for escape/avoidance performance on a human shuttle box. Both FR and VR schedules produced an inoculation against learned helplessness; escape performance by the helplessness group was significantly worse than that of FR and VR inoculation groups. These latter groups performed similar to the solvable and three control groups. Significantly worse than that of FR and VR inoculation groups. These latter groups performed similar to the solvable and three control groups. Significantly fewer subjects in the VR inoculation group exhibited avoidance responses than their counterparts in the FR inoculation group. despite similar escape performance. The findings indicate that learned helplessness can be prevented in humans and suggest different sources of interference produced by unpredictable and uncontrollable events.  相似文献   
122.
A model of subjective magnitude comparisons is explored, which assumes that subjects compare symbolic stimulus magnitudes with respect to a reference point. The reference point may be established implicitly by the question (e.g., “Which is larger?” vs “Which is smaller?”) or be presented explicitly (e.g., “Choose the stimulus closer to X.”). The model was tested in five experiments in which subjects judged which of two comparison digits was closer to (or further from) a reference digit. Regression analyses in three experiments revealed that reaction time depended on the ratio of the distances from the comparison items to the reference point. The other two experiments provided evidence that subjects can strategically vary the processes by which they compare stimuli to a reference point. The results indicated that subjects can perform various types of “analog arithmetic” using either the linear number scale or a nonlinear scale of subjective digit magnitude.  相似文献   
123.
In Experiment 1, 30 subjects at each of three age levels were shown pictures of unfamiliar “animals”. They were told two semantic attributes for each animal (e.g., kind and strong) and were asked to learn these sets so that, when shown a picture, the appropriate attributes could be recalled. The results indicated that the dimensional structure of the attributes had a strong effect on new learning for young children. Incongruent pairs of attributes (e.g., kind and ugly) were difficult to learn compared to congruent (e.g., kind and beautiful) or unrelated (e.g., kind and tall) sets. These results indicate: (a) Attribute structure is a factor in new learning; (b) 6-year-olds tend to organize the verbal labels for attributes into bipolar dimensions, rather than into independent clusters of attributes. The latter findings require reexamination of the meaning of previous word-association data which had been interpreted as indicating that 6-year-olds tend not to organize meanings bipolarly. Experiment 2 showed that the disruptive effects of incongruence on new learning disappears by college age.  相似文献   
124.
A field experiment investigated the effects of training in self-monitoring and goal-setting skills on classroom study behavior and academic achievement among elementary school students in an individualized mathematics program. In the Self-Monitoring Conditions, students were shown a simple system for observing and maintaining daily records of their own study behavior during their math classes; orthogonally, in the Goal-Setting Conditions, students were shown a simple method of setting and recording daily performance goals during their math classes. Exposure to self-monitoring procedures produced significant increases in both appropriate study behavior and in actual achievement in the mathematics program, while exposure to goal-setting procedures had no effect on either study behavior or academic achievement. Nor, contrary to expectation, did exposure to the goal-setting instructions enhance the effectiveness of the self-monitoring system. The implications of these results in terms of implicit and explicit models of self-reinforcement processes were discussed.  相似文献   
125.
Second- and sixth-grade (ages 7 and 11 years, respectively) subjects were instructed to learn simple Spanish vocabulary nouns using the keyword method. To remember a foreign word translation the keyword method user must: (1) associate the foreign word to an English word (the keyword) that sounds like part of the foreign word; and (2) remember an image of the keyword and translation referents interacting. Second-grade keyword users who were provided with interactive pictures remembered more vocabulary items than those who generated their own imagery links when given separate pictures of the keyword and translation referents. Second graders who generated their own linking images when given only the keywords and translation words recalled fewer items than both picture groups, and were not significantly different from control subjects. Sixth graders in the three imagery-link variations performed at comparable levels and better than control subjects. The results are in complete accord with previous speculations about the development of imagery strategies in children.  相似文献   
126.
The discriminative learning and transfer of compound and component problems were assessed in retarded subjects at two levels of intelligence. It was found that brighter subjects (MA = 10 years) found the component problems relatively easier than the compound problems to a greater extent than did the less developed subjects (MA = 5 years). The learning of compound solutions was shown to transfer positively to other compound problems and negatively to component problems. Component solutions were found to transfer positively to other component solutions and negatively to compound solutions. These dimensional transfer effects were interpreted to mean that both compound and component solutions were mediated and conceptual in nature. The developmental differences in relative usages of compound and component aspects of stimuli were viewed as the result of differences in direction of attention rather than of differences in complexity of processing.  相似文献   
127.
Criteria for distinguishing between attitude and response scale effects in “after-only” studies of source-recipient discrepancy were developed and applied in two experiments. These criteria refer to congeneric scales (i.e., multiple measures of the the same property, which may differ in origin, unit, and reliability). Persuasive information may function as a scale anchor, in which case it is expected to affect only that response scale to which it directly pertains. Alternatively, it may convice recipients to change attitudinal positions, and produce effects on all congeneric scales. In one experiment, the self-proclaimed leniency-sternness of a presiding judge in a manslaughter case was varied along with the sentence he imposed and his trustworthiness. In the second study, only the sentence was manipulated, while both leniency ratings and sentencing were measured as dependent variables. Both analyses revealed support for the response scale interpretation, in that effects were observed only on those scales that were directly manipulated.  相似文献   
128.
Key pecking of four birds was reinforced with food according to a two-component multiple variable-interval 1-minute variable-interval 4-minute schedule. In addition, key pecking was punished by a brief shock according to a variable-interval 30-second schedule during both components of the multiple schedule. The intensity of the shock was varied. For all birds, punishment had a stronger suppressive effect on the responding maintained by the leaner food schedule, and the ratio of responding during the two components of the multiple schedule became closer to the ratio of reinforcement as shock intensity was increased, as the relative law of effect predicts. At the higher shock intensity, there was some evidence that the ratio of responses overmatched the ratio of reinforcements.  相似文献   
129.
In Experiment I, lever pressing by squirrel monkeys was maintained under a sequence of variable-interval, multiple variable-interval variable-interval, and multiple variable-interval extinction schedules of food presentation. Negative induction (decreased responding in the unchanged component) occurred when one component of the multiple variable-interval variable-interval schedule was changed to extinction. Negative induction was transient over sessions; responding in the unchanged component usually recovered to a rate similar to that under the multiple variable-interval variable-interval schedule. Negative induction was not accompanied by consistent changes in the patterns of local responding within the unchanged component, and did not depend on whether component schedules were associated with localized (lever lights) or diffuse visual stimuli (houselights), or on whether the unchanged component was a 60- or 180-sec variable-interval schedule. In Experiment II, responding was maintained under a sequence of variable-interval and multiple variable-interval timeout schedules of food presentation. Negative induction occurred when responding declined gradually in the timeout component but not when responding declined abruptly. The nature of interactions in multiple schedules may depend on the species; negative induction was observed with squirrel monkeys under conditions similar to those that produce positive contrast with pigeons.  相似文献   
130.
The effects of pentobarbital and d-amphetamine were assessed on key pecking by pigeons under conventional single-key multiple schedules and under two-key multiple schedules in which discriminative stimuli appeared on one key (stimulus key) while pecks on a second key (constant key) produced food. Pecks on the stimulus key had no scheduled consequences. A 60-second variable-interval schedule operated in one component of each multiple schedule: either extinction or a 60-second variable-time schedule operated in the alternate component. When the alternate-component schedule was extinction, a high rate of responding was maintained in the variable-interval component of the single-key schedule; responding on both keys was maintained in the variable-interval component of the two-key schedule. Pentobarbital increased responding in the variable-interval component of the single-key schedule and increased stimulus-key, but not constant-key responding in that component of the two-key schedule. When the alternate-component schedule was changed to variable time, responding declined in the variable-interval component of the single-key schedule; stimulus-key responding was no longer maintained under the two-key schedule. Pentobarbital decreased responding in the variable-interval component of both schedules. With an exception, d-amphetamine only decreased responding in the variable-interval component of the single- and two-key schedules both when the alternate-component schedule was extinction and when it was variable time. The results suggest that the effects of pentobarbital, but not d-amphetamine, depend on the nature of the contingency (stimulus-reinforcer, response-reinforcer) that maintains responding.  相似文献   
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