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991.
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993.
Two studies were conducted to investigate the effects of perceived control in two men's prisons, one housing 181 inmates and the other housing 623 inmates. In both prisons, inmates' perceived control over the environment was found to be significantly related to their ratings of their living accommodations, experienced stress, and physical symptoms, even when type of cell was held constant.  相似文献   
994.
995.
Pigeon's observational learning of successive visual discrimination was studied using within-subject comparisons of data from three experimental conditions. Two pairs of discriminative stimuli were used; each bird was exposed to two of the three experimental conditions, with different pairs of stimuli used in a given bird's two conditions. In one condition, observers were exposed to visual discriminative stimuli only. In a second condition, subjects were exposed to a randomly alternating sequence of two stimuli where the one that would subsequently be used as S+ was paired with the operation of the grain magazine. In a third experimental condition, subjects were exposed to the performance of a conspecific in the operant discrimination procedure. After exposures to conspecific performances, there was facilitation of discriminative learning, relative to that which followed exposures to stimulus and reinforcement sequences or exposures to stimulus sequences alone. Exposure to stimulus and food-delivery sequences enhanced performance relative to exposure to stimulus sequences alone. The differential effects of these three types of exposure were not attributable to order effects or to task difficulty; rather, they clearly were due to the type of exposure.  相似文献   
996.
Superimposition of response-independent reinforcement   总被引:6,自引:6,他引:0       下载免费PDF全文
Studies that have superimposed response-independent reinforcement (or reinforcers scheduled by contingencies placed on the absence of responding) upon conventional response-dependent schedules are reviewed. In general, providing alternative sources of reinforcement reduced response rates below the levels observed when alternative reinforcement was absent. However, response-rate elevation was sometimes found, particularly when rates of superimposed response-independent reinforcement were low. Superimposition of schedules providing reinforcers contingent on the absence of responding usually produced more severe response-rate decrements than superimposition of response-independent reinforcement. A variant of Herrnstein's equation, which assumes that some of the alternative reinforcers function as if they were delivered by baseline response-dependent source of reinforcement, is in qualitative agreement with the overall body of results obtained, and can predict both increases and decreases in response rate as resulting from superimposed reinforcers.  相似文献   
997.
Thirty-one college undergraduates learned to touch abstract stimuli on a computer screen in arbitrarily designated “correct” sequential orders. Four sets of seven stimuli were used; the stimuli were arrayed horizontally on the screen in random sequences. A correct response (i.e., touching first the stimulus designated as first) resulted in that stimulus appearing near the top of the screen in its correct sequential position (left to right), and remaining there until the end of the trial. Incorrect responses (i.e., touching a stimulus out of sequence) terminated the trial. New trials displayed either the same sequence as the one on which an error had occurred (same-order correction procedure), or a new random sequence (new-order correction procedure). Whenever all responses occurred in the correct sequence, the next trial displayed a new random sequence. Each phase ended when five consecutive correct response sequences occurred. Initially, the same-order correction procedure increased control by the position as well as by the shape of the stimuli; also, it produced more errors, more total trials, more trials to mastery, and more individual patterns of reacquisition than were produced by the new-order procedure.  相似文献   
998.
This study assesses the relations between the ratings of clinicians and psychiatric inpatients on several anxiety and depression measures, as mediated by private self-consciousness. The overall concordance between clinicians' and patients' ratings is quite high, particularly on the depression measures. Levels of private self-consciousness do not appear to mediate concordance of structured behavior or symptom-based ratings of either anxiety or depression; however, there is limited support for levels of private self-consciousness mediating concordance between patients' global ratings of anxiety and clinicians' anxiety ratings.  相似文献   
999.
We examined task persistence and postperformance attributions by Type As and Bs on tasks that varied in level of difficulty. On the basis of past research, we hypothesized that Type As would be more self-serving than Type Bs in their attributions for success and failure. We also hypothesized that task persistence would differ among Type As and Bs and would be dependent on task difficulty and perceived task diagnosticity. Type As and Bs attempted multiple sets of anagrams that were either easy or difficult. We measured persistence by the number of anagram sets attempted, and, after task performance, we assessed attributions for success and failure. Results supported both hypotheses. Type As took more credit for success than for failure, whereas Type Bs did not provide reliably different attributions for success and failure. Furthermore, Type As persisted longer at the task when it was difficult and when it was viewed as relatively low in information value. Type Bs persisted longer at the task when it was difficult but viewed as relatively high in information value. Results are discussed in the context of current debates regarding the responses of Type As and Bs to performance settings.  相似文献   
1000.
Physiological measures have traditionally been viewed in social psychology as useful only in assessing general arousal and therefore as incapable of distinguishing between positive and negative affective states. This view is challenged in the present report. Sixteen subjects in a pilot study were exposed briefly to slides and tones that were mildly to moderately evocative of positive and negative affect. Facial electromyographic (EMG) activity differentiated both the valence and intensity of the affective reaction. Moreover, independent judges were unable to determine from viewing videotapes of the subjects' facial displays whether a positive or negative stimulus had been presented or whether a mildly or moderately intense stimulus had been presented. In the full experiment, 28 subjects briefly viewed slides of scenes that were mildly to moderately evocative of positive and negative affect. Again, EMG activity over the brow (corrugator supercilia), eye (orbicularis oculi), and cheek (zygomatic major) muscle regions differentiated the pleasantness and intensity of individuals' affective reactions to the visual stimuli even though visual inspection of the videotapes again indicated that expressions of emotion were not apparent. These results suggest that gradients of EMG activity over the muscles of facial expression can provide objective and continuous probes of affective processes that are too subtle or fleeting to evoke expressions observable under normal conditions of social interaction.  相似文献   
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