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331.
Disturbances in exploratory behavior and functional recovery in the Y and radial mazes following dopamine depletion of the lateral septum 总被引:1,自引:0,他引:1
The effects of 6-hydroxydopamine (6-OHDA) injected into the lateral septum in rats were investigated for spontaneous alternation behavior in a Y maze and for spatially oriented behavior in an 8-arm radial maze. The performance of the animals in these tests was assessed under two physiological states, food-satiated and food-deprived. The selective depletion of septal dopaminergic concentrations leads to behavioral disturbances in both the Y and the radial mazes. These deficits disappeared when the animals with 6-OHDA lesions were food-deprived. These results confirm other studies from our laboratory and support two conclusions. First, lesions of dopaminergic neurons lead to behavioral impairments which resemble those found after the total lesion of the structure they innervate. Second, these behavioral impairments are responsive to therapeutic treatments, manipulations of the internal or external environment, or the level of arousal, since under certain conditions a recovery of function can occur in the absence of dopaminergic neurons. These two points provide additional support for a nonspecific role for the dopaminergic neurons originating in the ventral tegmental area. These neurons could have a permissive role in the functioning of the forebrain structures they innervate. 相似文献
332.
The 2-deoxyglucose (2-DG) autoradiographic method was used to map metabolic activity in the brain of socially deprivated rats during an active avoidance test. The method investigated the effects of razobazam during this learning test. The animals were socially deprivated for 5 weeks. On the first experimental day the animals were trained to avoid a footshock by jumping onto a platform. During training and testing, the total number of avoidance responses was scored. On the second day during one 2-DG session of 40 min, razobazam increased the avoidance score by 18% as compared to controls. Autoradiographs were analyzed using a two-dimensional densitometric method. The analysis of the brain structures showed a 22% reduction of optical density in the nucleus habenularis lateralis, a 25% increase in the caudal part of the nucleus accumbens, and a 13% increase in the frontal cortex in rats treated with razobazam, but no change in the amygdala. These results provide a preliminary concept to explain how the new compound razobazam produced a better learning performance in socially deprivated rats. 相似文献
333.
Initial environment influences amphetamine-induced stereotypy: subsequently environment change has little effect 总被引:1,自引:0,他引:1
Saline-treated and amphetamine-treated (7 mg/kg, ip, immediate) male rats from a Sprague-Dawley substrain were observed in two test environments designed to elicit different investigative responses in normal rats. Snout contact with the substrate was generated by placing the rat in a small enclosed cage. Absence of snout contact was induced by placement of the rat on a square elevated platform. Detailed ethological records were kept of locomotion, rearing, sitting, grooming, gnawing, and sleeping throughout the 90-min session. Amphetamine-treated rats incorporated environmentally contingent bodily postures into their forms of stereotyped behavior. The postures were characteristic of those evinced initially by the saline-treated rats in the same test environment. The control rats showed appropriate changes in their investigative behavior when the apparatus was changed at 10 and at 30 min postinjection. The amphetamine-treated rats, however, were completely unresponsive to such changes at 30 min and only partially so at 10 min postinjection. It was concluded that there is a temporal gradient of decreasing readiness to modify repetitive behavior after a single, large dose of amphetamine. 相似文献
334.
Thirty-two children designated as hyperactive (ADD) were compared with an equal number of control subjects who were matched for age, sex, and verbal IQ. The subjects were tested on (1) a component selection task, measuring serial memory and incidental learning and (2) a cancellation task, assessing attentional variables and distractibility. No straightforward group differences were found on the component selection task, whereas hyperactive subjects made more omission and commission errors than controls on the cancellation task. It was concluded that a deficit in sustained attention and impulsivity best described the group differences. Age was also found to influence performance on a number of variables, including incidental learning on the component selection task and response rate and omission errors on the cancellation task. Because subjects in the hyperactive group were rated as extreme on a number of subscales not necessarily related to hyperactivity, the data were reexamined by multiple regression analyses. Subscales considered to be related both to hyperactivity and to conduct disorder were associated with different performance variables, indicating that each of these subscales provided some unique information.This study was supported by a grant from the Medical Research Council of New Zeland to the first author. The authors would like to thank the pupils and staff of Mt. Eden Normal Primary School and Newmarket School for taking part in the study, and the Auckland Education Board for granting approval for the study. We also thank Prof. J. S. Werry, Dr. J. Reeves, and Mrs. G. Elkind for assistance in locating some of the control subjects. Special thanks goes to Gail Elkind for assistance with the statistical analysis. 相似文献
335.
Jane A. Goldman Robert H. Lerman John H. Contois John N. Udall Jr. 《Journal of abnormal child psychology》1986,14(4):565-577
Despite speculation that sucrose consumption affects behavior, little empirical information is available. Accordingly, this study investigated the effect of sucrose consumption on the behavior of eight preschool children. Children were tested individually using a double-blind, crossover design. On separate mornings each child received 6 ounces of juice, sweetened on one morning with sucrose and on the other with an artificial sweetener. Children were observed for 90 minutes following the drinks, alternating between 15-minute sessions of work on structured tasks and 15-minute sessions of free play. Following the sucrose drink the children showed a decrement in performance in the structured testing situation, and they demonstrated more inappropriate behavior during free play. These differences in behavior were most pronounced approximately 45 to 60 minutes after the drinks. Thus, the study provides objective evidence in young children of a rather subtle, yet significant, time-dependent behavior effect of sucrose ingestion.This research was funded in part by grants from the General Research Grants Committee, University Hospital, Boston University Medical Center, and from the University of Connecticut Research Foundation. The project was conducted at the Clinical Research Center, Massachusetts Institute of Technology (National Institute of Health/General Clinical Research Center Grant 5M01-RR00088-20). We would like to express our appreciation to the many staff members of the Clinical Research Center for their extensive cooperation in helping us to plan and carry out this study, and to the director and staff of Technology Children's Center for their assistance in helping us to reach interested families. We also would like to thank the parents and children who participated in the study. Portions of this paper were presented at the annual meeting of the American Psychological Association, Toronto, August 1984. 相似文献
336.
B. H. Slater 《Philosophical Investigations》1986,9(3):205-215
337.
Pennypacker HS 《The Behavior analyst / MABA》1986,9(2):147-156
Highly effective technologies flowing from the discipline of behavior analysis have not been widely adopted, thus threatening the survival of the discipline itself. An analysis of the contingencies underlying successful technology transfer suggests the need for direct, empirical involvement in the marketplace in order to insure that the maximum demonstrable benefits reach the ultimate users. A successful example of this strategy of technology transfer is provided. Three areas of intense national concern-urban violence, illiteracy, and declining industrial productivity-provide immediate opportunities for the technologies of behavior analysis to secure the place of the discipline in the intellectual mosaic of the 21st century. 相似文献
338.
Inpatient Multimodal Therapy (imt) is a residential treatment program, lasting a maximum of 36 weeks, for patients with severe neurotic symptoms. A group of
44 chronic obsessive-compulsive patients and a group of 40 chronic phobic patients were treated in order to assess the outcome
and the process of treatment and to identify prognostic factors associated with the effect. At follow-up—on average, eight
months after discharge—it was found that 60% had improved, 32% had remained the same, and 8% had deteriorated, indicating
that, in general, the treatment was beneficial. That these effects were long-lasting is supported by the fact that, at follow-up,
78% of all patients were no longer receiving treatment, 18% were receiving outpatient or day treatment, and 4% were receiving
inpatient treatment. Phobic patients appear to have gained more from the multimodal approach than did obsessive-compulsive
patients, as indicated by the fact that the severity of symptoms decreased as they improved in rational thinking, assertiveness,
and arousal. By contrast, obsessive-compulsive patients relapsed more than phobic patients did. This was attributed to the
fact that the former gained less from the rational-emotive training, denied problems with assertiveness, and did not practice
the acquired relaxation skills. It further appeared that a favorable outcome could be induced in patients who (1) expressed
relatively mild symptoms in this otherwise severe group, (2) reported relatively few additional complaints, (3) could clearly
indicate interpersonal problems, and (4) did not use psychotropic drugs. These prognostic factors are so widespread that not
much weight can be ascribed to them. Yet they are useful for indication ofimt until better predictors are found. 相似文献
339.
This study examined the implications for social comparison theory of the proposition that women have lower self-confidence than men when there is a socially defined standard of performance. To this end, it was hypothesized that women would judge themselves to be similar to a lower ranked person, whereas men would judge themselves to be similar to a higher ranked person. Furthermore, it was hypothesized that women would choose to see a score lower than their own, whereas men would choose to see a score higher than their own. The results on the measure of similarity indicated that men did judge themselves to be similar to a higher ranked person, whereas women showed no consistent preferences in their judgments of similarity. The results on the choice of a comparison other were not as clear-cut. 相似文献
340.
This study examined the relationship of parental education, race, and gender to sex-role stereotyping in five-year-old kindergartners. A significant effect for race and parental education level was noted. White children gave more stereotyped responses than did black children, and children whose parents were in the middle- and high-educational levels gave more stereotyped responses than did children whose parents were in the low-educational level. A significant interaction was also found between educational level of parents and race. White children tended to give more stereotyped responses as the educational level of their parents increased; this trend was not evident for black children. No significant differences in stereotyping were noted between the sexes.To whom requests for reprints or information concerning the Bardwell-Sietsema Sex Stereotype Scale should be addressed at Department of Elementary Education, East Texas State University, Commerce, Texas 75428. 相似文献