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861.
Drug-behavior interaction history: modification of the effects of morphine on punished behavior. 总被引:1,自引:1,他引:0 下载免费PDF全文
Squirrel monkeys were trained to respond under a multiple fixed-interval, fixed-interval schedule in which the first response after 5 min terminated a visual stimulus in the presence of which electric shocks could occur. During one component of the schedule, correlated with one color of stimulus lights, every 30th response also produced electric shock; responding was suppressed during this component to approximately 10 to 12% of that occurring in the alternate component in which responding was not punished. In contrast to previous research, morphine (0.03 to 1.0 mg/kg) increased punished responding. Unpunished responding, however, was either not affected or decreased at doses of morphine that increased punished responding. Increases in rate of punished responding also occurred when the single-schedule punishment condition was studied alone in these animals. Subsequent experimentation, which systematically analyzed the development of the rate-enhancing effects of morphine on punished responding, involved the study of drug effects in additional monkeys trained initially under a single-schedule punishment condition. The effects of morphine on punished responding were studied before, after, and then during exposure to the multiple schedule that included a component in which responding was not punished. Increases in response rate with morphine did not occur until it was administered during exposure to the multiple schedule that included a component in which responding was not punished. As with the other monkeys, once the rate increases in punished responding occurred under the multiple schedule, these effects of morphine persisted, even when the multiple schedule was removed.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
862.
Theories of observing differ in predicting whether or not a signal for absence of reinforcement (S−) is capable of reinforcing observing responses. Experiments in which S− was first removed from and then restored to the procedure have yielded mixed results. The present experiments suggest that failure to control for the direct effect of presenting S− may have been responsible. Pigeons and operant procedures were used. Experiment 1 showed that presentations of S−, even when not contingent on observing, can raise the rate of an observing response that was reinforced only by presentations of a signal (S+) that accompanied a schedule of food delivery. Experiment 2 showed that this effect resulted from bursts of responding that followed offsets of S−. Experiment 3 showed that, when the presence of S− was held constant, lower rates occurred when S− was dependent on, rather than independent of, observing. These results support theories that characterize S− as incapable of reinforcing observing responses. 相似文献
863.
In previous studies subjects who have learned a positioning response with kinesthetic feedback tended to make greater errors when visual feedback was provided during later trials. These subjects have always performed with both kinesthetic and visual feedback available. This study determined whether subjects with only visual feedback would produce errors similar to those who received kinesthetic plus visual feedback. Blindfolded subjects learned to move a handle to a criterion location with knowledge of results following each trial. Subjects then were assigned to one of three experimental groups, with only kinesthetic feedback, with kinesthetic plus visual feedback, or with only visual feedback. Subjects had 9 trials without knowledge of results in these feedback conditions. When visual feedback was available, subjects tended to make longer response errors. This finding replicates previous studies. Also, the similarity of performances from the conditions with visual feedback indicated the dominance of visual information in the condition with kinesthetic plus visual feedback. 相似文献
864.
L Zusne 《Perceptual and motor skills》1986,62(3):729-730
The count of publications on geometric-optical illusions and the bibliography of extant books on the topic are brought up to date. The number of publications now exceeds 1100 and the number of books is 35. 相似文献
865.
Parieto-occipital EEG alpha was recorded bilaterally, while 20 high- and 20 low-hypnotizable women performed one left-hemisphere and one right-hemisphere task of low difficulty and two other comparable tasks of high difficulty. Every task was performed twice, once with eyes open and once with eyes closed. All subjects were right-handed. The tasks were originally selected to be of high and low difficulty. The subjective rating of task-difficulty was also evaluated. The integrated amplitude alpha and the alpha ratio (R-L/R + L) were the dependent variables. The highly hypnotizable women showed significantly higher alpha amplitude in eyes-closed condition than the low scorers; this difference disappeared during task performance and in the eyes-open condition. The left-tasks showed lower alpha amplitude in both hemispheres than right-tasks and baseline. The right-hemisphere alpha amplitude was lower than left in all experimental conditions. On tasks of high and low difficulty there was different hemispheric behavior on right and left tasks. Performance reflecting the right and left hemispheres in the low-difficulty condition showed no changes between baseline, right- and left-tasks, while under high difficulty there was a decrease in alpha amplitude in the right and even more marked decrease in the left hemisphere during left-tasks. The pattern of task effects for ratio scores was the same as for alpha amplitude, however, despite the analysis of alpha scores, an interaction of hypnotizability X task-difficulty was detected. The highly hypnotizable women showed less negative alpha ratio during a task of low difficulty than during tasks of high difficulty; the reverse was true for the low-hypnotizable women. Finally, the highly hypnotizable subjects showed less subjective difficulty during performance than the low scorers. 相似文献
866.
Relationship between specific disfluency variables and dichotic listening in stutterers 总被引:1,自引:0,他引:1
86 stutterers' disfluency patterns were examined in relation to their laterality preferences. Results suggest that young stutterers are a heterogeneous group and that specific disfluency variables were not related to ear preferences on a dichotic consonant-vowel listening task. 相似文献
867.
The comparable worth controversy has generated much discussion about the appropriate valuation of job worth. To date, academic inquiries into the measurement of job worth have focused primarily on job evaluation; however, recent court decisions suggest that market wages are a more compelling indicator of job worth than are job evaluation results. This paper examines the construct of "market wage" and the process by which it is measured (wage surveys). It is argued that both the construct and the measurement of the market wage have not been sufficiently examined by either academics or the courts. Implications for pay administration and future research are noted. 相似文献
868.
VALIDITY GENERALIZATION RESULTS FOR LAW ENFORCEMENT OCCUPATIONS 总被引:1,自引:0,他引:1
The Schmidt-Hunter interactive validity generalization procedure was applied to validity data for cognitive abilities tests for law enforcement occupations. Both assumed artifact distributions, and distributions of artifacts constructed from information contained in the current sample of studies were used to test the hypothesis of situational specificity and to estimate validity generalizability. Results for studies using a criterion of performance in training programs showed that validities ranged from .41 to .71, and for four test types the hypothesis of situational specificity could be rejected using the 75% decision rule. For the remaining test types, validity was generalizable, based on 90% credibility values ranging from .37 to .71. Results for studies using a criterion of performance on the job indicated that the hypothesis of situational specificity was not tenable for three test types, which had validities between .17 and .31. For the remaining test types, estimated mean true validities ranged from .10 to .26 and were generalizable to a majority of situations. Results for both groups of studies were essentially identical for the two types of artifact distribution. Possible reasons for the apparently lower validities and lesser generalizability for job performance criteria are discussed, including possible low validity of the criterion (due to lack of opportunity by supervisors to observe behavior) and the potential role of noncognitive factors in the determination of law enforcement job success. Suggestions for specifically targeted additional research are made. 相似文献
869.
870.
With the Structured Psychopathological Evaluation-System (SPES) an instrument existed for employment of objective criteria. This study was designed to present an evaluation system based on new scientific results, that is applying on the strength of a reduced catalogue of symptoms (94 compared with 198 Items at SPES-A) to clinical routine. Additional findings differentiated by this system be able to classify by the help of an operational decision system. 相似文献