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281.
Thirty-eight chronically mentally disabled patients who were invited to join a newly established, vocationally oriented, day treatment program in Raleigh, North Carolina, served as subjects. We attempted to determine whether demographic and psychosocial characteristics significantly differed among groups of clients who dropped out of, remained in, or refused membership in this community-support program. A variety of demographic, expectancy, psychological, and psychosocial measures were administered to each subject. Most significant was the finding that the subjects' perceived level of help and support from friends was a significant determinant of the level of program participation. Those subjects who refused to participate (refusers) perceived themselves as receiving proportionately less support than did members of the other two groups (dropouts and remainers).  相似文献   
282.
Three pigeons pecked at letters of the alphabet and at the symbol "?" displayed on a computer-driven cathode ray screen. A 4 by 4 matrix of infrared emitting and detecting diodes and associated circuitry identified the location of a pigeon''s responses to the screen. Responses at the target letter T were probabilistically reinforced with food whenever T appeared in a string of three letters in the middle of the screen. Responses at the symbol "?" appearing below this string were probabilistically reinforced whenever T did not appear. The letter F anywhere in the three-character string either strongly predicted the occurrence of the target letter T, in two conditions, or predicted its nonoccurrence, in a third. This manipulation of the frequency with which the familiar letter F predicted T was shown to change the function relating probability of a correct peck at the symbol "?" to the number of Fs in the string. This effect may be interpreted as an instance of the phenomenon where an organism''s acquired knowledge changes what it sees.  相似文献   
283.
284.
The publication in 1973 of Student Counselling in Practice signalled a new phase in the development of both careers and counselling services in the tertiary sector. The emergence of the professional careers adviser in higher education is described alongside the key role of the Association of Graduate Careers Advisory Services. The gradual professionalisation of student counselling is shown to have taken a different form, as a result of the policies of the Association for Student Counselling with its insistence on role definition and the accreditation of practitioners. Developments in further education are briefly reviewed, and a final section considers the present situation and possible future trends.  相似文献   
285.
The effects of dopaminergic depletion of the nucleus accumbens was tested in various behavioral tasks such as alternation, spatial discrimination, and reversal learning, and in an extinction paradigm in a T maze. Animals with lesions showed impairment of spontaneous alternation behavior, disturbances in the acquisition of spatial discrimination, and great difficulty in reversing previously learned habits. In the extinction phase, experimental animals are unable to adjust their behavior, and continue to choose the previously reinforced arm of the T maze. It is suggested that the nucleus accumbens plays an important role in the transition of motivation into action, and that dopamine has a facilitatory influence on the mediation of these processes.  相似文献   
286.
The effects on aggressive behavior, open-field activity, and pain threshold of bilateral microinjections of serotonin (20 micrograms) and quipazine (20 micrograms), the direct serotonergic receptor agonist, into the cortico-medial amygdala were investigated in Wistar rats. Both drugs significantly prolonged the attack latency in isolated killer rats (predatory aggression model), and suppressed the incidence of aggressive postures/attacks in shock-induced fighting test (affective aggression). The only difference in the open-field behavior was the lower number of central square entries in drug-treated compared to saline-injected rats. None of the substances produced any significant change in jump threshold. It is concluded that stimulation of serotonin receptors within the amygdala produces inhibition of affective and muricidal behavior in isolated rats. The effect does not seem to be dependent on changes in general activity and pain sensitivity.  相似文献   
287.
The priming effects of ignored information have been studied in Stroop displays (Neill, 1977) and with spatially superimposed drawings (Tipper, in this issue); naming of probes related to ignored primes is delayed in these experiments (“negative priming”). This negative priming effect is confirmed in a list reading task in Experiment 1, which used partially superimposed letters, and Experiment 2, which used spatially separated letters. Furthermore, Lowe (1979) using Stroop colour words observed that changing the nature of the probe such that it did not require selection from a competing word reversed the priming effects of the ignored word from inhibition to facilitation. Experiment 3 confirmed this observation when subjects selected a red letter from a green letter. Two models are suggested to account for this result. In the first, negative priming is a product of the ignored prime and subsequent probe being encoded both as a stimulus to be ignored and one to be named (Allport, Tipper and Chmiel, in press; Lowe, in press). This dual encoding is ambiguous, requiring further processing before response can be output. The other model suggests that negative priming reflects inhibition of response to ignored information, slowing naming latencies to probe stimuli that require the same response. Experiment 4 attempts to differentiate between the models, and the latter inhibition view is preferred.  相似文献   
288.
The pathological left-handedness syndrome   总被引:3,自引:0,他引:3  
A clinical syndrome of pathological left-handedness (PLH) is proposed to identify the pattern of correlative changes in lateral development associated with early brain injury in some manifest left-handers. This syndrome is believed to be caused by a hemispheric lesion that is predominantly left-sided (or bilateral asymmetric), which onsets before Age 6, and which encroaches upon the critical speech zones of the frontotemporal/frontoparietal cortex. The pattern of changes may include any or all of the following features: shifts in manual dominance, trophic changes in the extremities, transfer of hemispheric speech, and/or intrahemispheric reorganization of visuospatial cognitive functions. Although some of these correlates of PLH have long been known, they have not been recognized as an interrelated pattern of traits that constitute a clinical syndrome. Identification of these individuals, all manifest left-handers, will be shown to have implications for diagnosis/remediation and for models of recovery of function.  相似文献   
289.
The present study explored the factors that contribute to mothers' decisions to seek urgent medical attention for their children when symptoms are not of a traumatic nature. One hundred mothers seeking treatment for their children at a prepaid clinic completed a questionnaire eliciting their expectations regarding the course of their children's problems, seriousness of the problems, perceived responsibility for the symptoms, and extent to which a variety of factors contributed to their decisions to seek treatment. Demographic data and information about each child's symptoms and medical history were also obtained. Four major "reasons for seeking treatment" factors were identified: family history of the presenting complaint, worry regarding the symptoms, situational variables, and the extent of the child's illness behavior. The appropriateness of the visit, delay in seeking treatment, and frequency of mothers' use of the pediatric clinic were predicted by the nature of the presenting symptoms (particularly the presence of fever), the ages of the mother and child, and two of the reasons for seeking treatment factors (i.e., family history and child's illness behavior). The present study suggests that mothers pay more attention to presenting symptoms and to the children's behavior than to psychosocial stressors in deciding to seek urgent care.  相似文献   
290.
Previous studies have examined intra-individual aggregation in the use of cigarettes, alcohol, and coffee by examining the co-occurrent use of any pair of these three substances. A recent literature review failed to find a single investigation that studied use of all three in the same sample. In the present study, co-occurrent use of all three of these substances was examined in crossvalidated subsamples of 226 male and 245 female healthy, community-living, middle-class Americans. A log-linear analysis was used to compare the proportion of smokers, ex-smokers, and nonsmokers categorized as users of more or less amounts of coffee and alcohol. Although most of the intercorrelations were not strong, the results indicate that for both sexes, smokers and ex-smokers were more likely than nonsmokers to drink greater amounts of alcohol and coffee. Furthermore, for smokers, ex-smokers, and nonsmokers, a majority of individuals who reported drinking more alcohol also reported drinking more coffee. Interestingly, the coffee and alcohol consumption levels of ex-smokers resembled those of smokers more than those of nonsmokers. Also, ex-smokers reported drinking more wine and decaffeinated coffee than either smokers or nonsmokers. Finally, the number of cigarettes smoked per day (daily quantity) was positively related to total alcohol and coffee consumption in men, but not in women. Further studies are recommended to examine the role of individual differences in the development, maintenance, and modification of these three appetitive habits and their co-occurrence.  相似文献   
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