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991.
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993.
This experiment was designed to determine the relative effectiveness of teacher and counselling approaches in the reduction of disruptive or inappropriate classroom behavior. Inappropriate classroom behavior frequencies of 12 academically low achieving, seventh-grade, black male students, with a reported high rate of inappropriate classroom behavior, were recorded. Three groups, with nearly equal mean inappropriate behaviors, were randomly assigned to one of three treatment conditions: behavioral counselling, client-centered counselling, or no counselling. Each counselling group received fifteen 30-minute counselling sessions, at a rate of two to three times a week. In addition to counselling, all students subsequently received teacher approval within the classroom. Results indicated that the teacher was able to reduce inappropriate behavior more than any counselling group. There were also indications that behavioral counselling, but not client-centered counselling, was moderately helpful in reducing inappropriate classroom behavior.  相似文献   
994.
995.
The purpose of the present study was to determine whether the demasculinizing and feminizing effects of prenatal stress (i.e., stress applied to the mother during pregnancy) in rats reported previously are mediated by activation of the maternal pituitary-adrenal axis. Neither whole-body restraint, with or without hyperthermia, nor ACTH treatment during the last third of gestation had any reliable effect on masculine or feminine sexual behavior in male Sprague-Dawley offspring, although these treatments produced maternal pathology and evidence of maternal adrenocorticoid release. Significant littermate similarity was found for almost every morphological and behavioral measure. Failure to control for the litter variable may account for many previously reported effects of prenatal stress on sexual behavior in rats. The discrepancy between the present and earlier findings is discussed in terms of methodological and theoretical considerations.  相似文献   
996.
After surgical removal of the neocortex and hippocampal formation, rats retained most of the movement patterns of locomotion, climbing, grooming, feeding, and fighting. However, forepaw immobility during swimming was abolished. Feeding behavior was suppressed temporarily but recovered partially. The distinctive postures of sleep and walking and a circadian rhythm of motor activity were retained. However, behaviors were often not performed at the appropriate time and place. The normal sequence of grooming behavior was disrupted; food hoarding and social behavior were essentially abolished. Removal of the neocortex alone had much the same effect as removal of neocortex and hippocampus together. Removal of hippocampus alone produced only a mild disruption of behavior. It is suggested that ascending nonspecific projections to the cerebral cortex play an important role in the moment-to-moment control of behavior but are not essential for the sleep-waking cycle.  相似文献   
997.
Lesions localized to specific areas of the amygdala and overlying cortex in rats produced differential effects in several behavioral tasks. Three different types of lesions were tested: central, basolateral, and cortex lateral to the amygdala. Lesions restricted to the central nucleus produced increased activity on all parameters studied in an open-field test, but the other two groups were not changed. In one-way active avoidance all three groups with lesions showed deficits. The most pronounced change was observed in the central group. All groups showed the same degree of retention loss, but in forced extinction of one-way active avoidance after retraining, the cortical and basolateral groups were most defective. A fear-reduction hypothesis is proposed for the central lesion. The basolateral and cortical areas may be more specifically involved in passive avoidance behavior.  相似文献   
998.
999.
Two experiments investigated visual attention in human infants. In one experiment, babies looked longer at more than at less saturated colors. In a second experiment, babies looked longer at gratings aligned along the horizontal and vertical orthogonals than along the obliques. Because saturated colors and orthogonal stimulation elicit greater activity in visual system neurons and greater amplitude evoked potentials than desaturated colors or oblique stimulation, these two experiments support the hypothesis that the simple visual stimuli to which infants preferably attend are those that are particularly appropriate in stimulating the geniculostriate or primary visual system. The ethological significance of this taxic mechanism and its utility and function in perception, cognition, and aesthetics are underscored.  相似文献   
1000.
An experiment was conducted to test the proposition that rewards undermine or enhance intrinsic interest in a task to the extent that individuals interpret their behavior as being motivated by the reward. It was predicted that when subjects were denied the opportunity to develop and confirm this attribution, rewards would not produce an undermining effect, but rather would enhance dispositions and behavior. Subjects were recruited to evaluate a new sugar-free soft drink. Two levels of incentives (reward-no reward), two levels of examination (opportunity-no opportunity), and three levels of outcome (good-neutral-poor) were employed. The results support the prediction that an incentive's effect depends on the examination opportunity. In the examination condition, rewarded subjects attributed their behavior more to external factors than did unrewarded subjects, but gave more negative product evaluations only after tasting it. In the no examination condition, there were no differences in the attributions made by rewarded and unrewarded subjects, and rewarded subjects were more positively disposed toward the product both before and after tasting it. These results are explained as a consequence of two properties of rewards, enhancement through reinforcement and undermining through discounting, and of hypothesis-testing processes.  相似文献   
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