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901.
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
902.
Deprivation and satiation: The interrelations between food and wheel running 总被引:2,自引:1,他引:1 下载免费PDF全文
Two experiments were designed to assess whether depriving rats of food would increase the reinforcement effectiveness of wheel running (Experiment 1) and whether satiation for wheel running would decrease the reinforcement effectiveness of food (Experiment 2). In Experiment 1, a progressive-ratio schedule was used to measure the reinforcement effectiveness of wheel running when rats were deprived or not deprived of food. Completion of a fixed number of lever presses released a brake on a running wheel for 60 s, and the response requirement was systematically increased until the rat stopped pressing or until 8 hr had elapsed. The ratio value reached (and the total number of lever presses) was an inverted-U function of food deprivation (percentage body weight). In Experiment 2, when wheel running preceded test sessions, fewer food-reinforced lever presses were maintained by the progressive-ratio schedule, and responding occurred at a lower rate on a variable-interval schedule. An interpretation of these results is that deprivation or satiation with respect to one event (such as food) alters the reinforcement effectiveness of a different event (such as access to wheel running). 相似文献
903.
It is suggested that molar streams of behavior are constructed of various arrangements of three elementary constituents (elicited, evoked, and emitted response classes). An eight-cell taxonomy is elaborated as a framework for analyzing and synthesizing complex behavioral repertoires based on these functional units. It is proposed that the local force binding functional units into a smoothly articulated kinetic sequence arises from temporally arranged relative response probability relationships. Behavioral integration is thought to reflect the joint influence of the organism's hierarchy of relative response probabilities, fluctuating biological states, and the arrangement of environmental and behavioral events in time. 相似文献
904.
Relationship between Knapp's metaphor scale of attitudes toward time and subjective estimation of fixed time intervals, measured by a modification of Lovett Doust's method, was described. Results were discussed within the framework of studies relating the measurements of cognitive styles and altered consciousness states to the dilated or accelerated perceptions of time. 相似文献
905.
V D Lutzer 《Perceptual and motor skills》1986,62(3):959-966
A match-to-sample task and a preference-ranking procedure were used to provide predifferentiation experiences on a color discrimination for 6- and 8-yr.-old children. The subjects included an educable mentally retarded 8-yr.-old group, an average 8-yr.-old group, a gifted 6-yr.-old group, and an average 6-yr.-old group. Mental age was the best predictor of success on task. A significant interaction of sex and teaching method suggests an advantage of girls in this group in instructional situations in which the perceptual learning task and testing tasks are not exactly the same. Girls did better than boys when a different response for task content was required in testing from that in teaching. Boys and girls performed similarly when the training task was the same as the testing task. 相似文献
906.
Relationships between experiences, processing style, and sex-related differences in performance on spatial tests 总被引:1,自引:0,他引:1
53 female and 45 male undergraduates were administered the Spatial Antecedents Questionnaire (Activities, Academic Courses, Self-assessments, and Environmental Mapping subscales), the Spatial Dimensionality Test (Embedded Figures, Card Rotations, Paper Folding, Surface Development, Horizontal/Vertical Rotations, and Cube Perspectives subtests), and Revised-Individual Differences Questionnaire of Paivio. Scores from the Academic Courses and Self-assessment scales accounted for the most variability in spatial performance. Visual processing style correlated with performance on spatial tests for men, but not for women. Different patterns of activities and experiences correlated with spatial test performance for men and women. 相似文献
907.
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
908.
K Leonhard 《Psychiatrie, Neurologie, und medizinische Psychologie》1986,38(12):703-709
Many years ago the author, jointly with a psychologist, described a patient who, in spite of her alleged idiocy, showed an exceptional musical capacity. However, in the meantime the author has recognized and described early childhood catatonics and, as a consequence of this new knowledge, he has to admit an error. Even according to our then findings it would have been identifiable that, as has been confirmed now by follow-up, the patient is suffering from catatonia, starting in infancy. The high musical performance, then arousing our greatest astonishment, is now explicable, for childhood schizophrenics do not develop general mental deficiency but only specific circumscribed deficits. 相似文献
909.
K Leonhard S von Trostorff 《Psychiatrie, Neurologie, und medizinische Psychologie》1986,38(8):443-449
According to our investigations the incidence of cataphasia, which is a subtype of schizophrenia, has become more common in the last years and on average, has started earlier in life. As the central disorder of this illness concerns thinking perhaps there exists a relation of our finding to the rapid modern development of techniques, insofar as the cognitive function is overstrained in childhood and adolescence, when the nervous system has not matured yet. Introverted individuals seem to be at a particular risk. However, it must not be disregarded that cataphasia is an inherited illness which cannot be caused by external influences, but can only be promoted in its manifestation. 相似文献
910.
R Goertchen N Grunow T Münchow E Goertchen 《Psychiatrie, Neurologie, und medizinische Psychologie》1986,38(3):128-132
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