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951.
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   
952.
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   
953.
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   
954.
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   
955.
The purpose of this study was to assess difference in academic performance among myopic, hyperopic, and emmetropic children who were learning disabled. More specifically, myopic children were expected to perform better on mathematical and spatial tasks than would hyperopic ones and that hyperopic and emmetropic children would perform better on verbal measures than would myopic ones. For 439 learning disabled students visual anomalies were determined via a Generated Retinal Reflex Image Screening System. Test data were obtained from school files. Partial support for the hypothesis was obtained. Myopic learning disabled children outperformed hyperopic and emmetropic children on the Key Math test. Myopic children scored better than hyperopic children on the WRAT Reading subtest and on the Durrell Analysis of Reading Difficulty Oral Reading Comprehension, Oral Rate, Flashword, and Spelling subtests, and on the Key Math Measurement and Total Scores. Severity of refractive error significantly affected the Wechsler Intelligence Scale for Children--Revised Full Scale, Performance Scale, Verbal Scale, and Digit Span scores but did not affect any academic test scores. Several other findings were also reported. Those with nonametropic problems scored higher than those without problems on the Key Math Time subtest. Implications supportive of the theories of Benbow and Benbow and Geschwind and Behan were stated.  相似文献   
956.
957.
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   
958.
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   
959.
Based on 2130 autopsies with a hypertension it is reported on the hypertensive CNS-lesions. The frequency of encephalomalacia was 12%. By 9.7% was founded brain haemorrhages. The relapse rate of haemorrhages was about 5%. The encephalomalacia existed by way of secondary finding in 24.7%, and the haemorrhage in 2.2%. The investigations showed an important arteriosclerosis by 39.8% in haemorrhages and by 51.6% in brain infarct. It was remarkable by the hypertensive brain haemorrhages a dominant right hemisphere.  相似文献   
960.
The authors sum up the most important basic principles of diagnostics and genetics of the schizophrenic psychoses from the viewpoint of genetic counseling for the practising psychiatrist and medical geneticist. Regarding genetic counselling strategy, in addition to nosological considerations, they stress the importance of socio-cultural and social psychological factors and of the emotional atmosphere in the family, which should all be taken into account together. Because of the special situation of schizophrenic (and in general, psychiatric) patients and their families, they regard it as advisable to set up a separate psychiatric genetic counselling service.  相似文献   
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