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921.
Donald J. Salmon Joseph J. Pear Beverley A. Kuhn 《Journal of applied behavior analysis》1986,19(1):53-58
Generalization of four retarded children's object naming responses to stimuli in the natural environment was assessed after training with either objects or pictures of the objects. Generalization was typically greater after training with objects. In a second experiment, half of the stimuli that showed little generalization were retrained by alternating the original training object with an object that belonged to the same stimulus class as the training stimulus. The other half were simply retrained using the object. The alternating procedure resulted in substantial increases in generalization to untrained objects. 相似文献
922.
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
923.
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
924.
Preference for less segmented fixed-time components in concurrent-chain schedules of reinforcement 总被引:1,自引:1,他引:0 下载免费PDF全文
A concurrent-chain procedure was used to examine choice between segmented and less segmented response-independent schedules of reinforcement. A pair of independent, concurrent variable-interval 60-s schedules were presented in the initial link, along with a 1.5-s changeover delay. A chained fixed-interval fixed-time and its corresponding tandem schedule constituted the terminal links. The length of the fixed-interval schedule in the terminal link was varied between 5 s and 30 s while that of the fixed-time schedule was kept at 5 s over conditions. The first components of both terminal-link schedules were accompanied by the same stimulus. Except in the baseline condition, the onset of the second component of the terminal-link chained schedule was accompanied by either a localized (key color) or a nonlocalized (dark houselight) stimulus change. Stimulus conditions were constant during the terminal-link tandem schedule. With three exceptions, pigeons demonstrated a slight preference for the tandem over the chained schedule in the terminal link. Furthermore, this preference varied inversely with the length of the first component. In general, these results are consistent with previous studies that reported an adverse effect on choice by segmenting an interval schedule into two or more components, but they are inconsistent with studies that reported preference for signaled over unsignaled delay of reinforcement. 相似文献
925.
Speech-mediated retention in dyslexics 总被引:2,自引:0,他引:2
Dyslexics (6 to 9 yr. old) and a control group of 12 normal readers (second-graders) were tested on a memory task with rhyming and non-rhyming items. The most important finding is that both groups were penalized by rhyme, indicating speech coding. It was observed that the dyslexics were not less penalized by rhyme than were controls. The present results are compared with those of other recent studies. 相似文献
926.
The purpose of this study was to examine the influence of age, sex, etiology, and degree of hearing loss on the static and dynamic balance performance of hearing impaired children and youth (N = 132), ages 3 to 14 yr. The subjects were individually assessed on Items 2 and 7 of Subtest 2 of the Short Form of the Bruininks-Oseretsky Test of Motor Proficiency. As expected, performance on both tasks improved with chronological age. In comparing the performance of subjects by etiology, only one significant difference emerged; those with genetic deafness were superior on static balance to those whose deafness was idiopathic. However, the mean scores for the genetic group were superior for both balance tasks. The sex of the child as well as extent of hearing loss did not affect performance in either task. 相似文献
927.
A Satow 《Perceptual and motor skills》1986,62(3):983-998
In 1982 Satow proposed four hypothetical properties determining mechanisms of individual differences in perceptions; these were supported by results of a factor analysis of responses to a 58-item check list. Present work confirmed the four properties (intense sensitivity, temporal sensitivity, sensory-motor reactivity, and possible range of total stimuli), and obtained a property, preference for intense and prolonged stimuli, from a principal component analysis of data from a 60-item list given to 316 subjects. The 60-item list is a revised version of the 58-item list which asked subjects about their subjective sensitiveness and preferences for environmental sensory stimuli (visual, auditory, olfactory, and tactile). Within subjects relationships among these properties are interindependent, since for individuals correlations of factor-score estimates between pairs of these properties were near zero. This interindepedence supported a model of four hypothetical types of individuals, explaining the individual differences on the grounds of the relations among the properties. 相似文献
928.
R F?tzsch R Podemski A Brzecki R Bogdańska 《Psychiatrie, Neurologie, und medizinische Psychologie》1986,38(9):518-525
Twenty six clinically healthy smokers were studied with transient pattern visual-evoked potentials. In comparison with a sample of "normal" subjects we found a difference of some parameters (P less than 0.05): the P2-latency and the interocular difference of latency on average were 6-7 ms respectively 2 ms larger. Thirteen subjects have had a prolonged P2-latency (P less than 0.05) and/or a difference in interocular latencies larger than 5 ms. These findings may suggest on subclinical disturbances of visual system and indicators of an special sensitivity of that person. The findings are possibly related to tobacco-alcohol amblyopia. 相似文献
929.
W Kallenbach G Küllertz G Fischer A Barth 《Psychiatrie, Neurologie, und medizinische Psychologie》1986,38(8):456-463
The dipeptidyl-peptidase activity of 650 liquores cerebrospinalis was obtained by means of the substrate Gly-Pro-NHNp (Gly-Pro-4-nitroanilid) at pHs of 5.5 and 7.4. In comparison with a reference collective, the suitability of the method as a supplementary liquor parameter in neurological psychiatric diagnosis was examined. The introduction of the measurement at pH 7.4 can be particularly recommended for the distinguishing of bacterial and nonbacterial meningitis. 相似文献
930.
Placebo-like effects of education about rational-emotive therapy 总被引:1,自引:0,他引:1