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171.
Periadolescent rats exhibit a number of behavioral differences in comparison with younger or older animals. For instance, periadolescents tend to show enhanced acquisition of simple active avoidance tasks, but impaired acquisition of more complex appetitive and aversive discriminations. In this experiment, rats were trained on a simple passive avoidance task at one of three ages, as weanlings (25 days), periadolescents (35 days), or young adults (45 days). Training occurred in the presence of both a redundant discriminative stimulus and a specified, redundant contextual stimulus. The periadolescents did not differ from either younger or older rats in rate of learning the passive avoidance task. The retention performance of these animals was then tested following a change in either, neither, or both of the redundant cues. When a measure of performance that controls for baseline activity was used, it was observed that periadolescents were not disrupted by a change in the redundant discriminative stimulus, a cue change that clearly disrupted performance in 25- and 45-day-old animals, and tended to be more disrupted by the contextual change than younger or older rats. It is hypothesized that the alterations in performance exhibited by periadolescents may be related to an ontogenetic alteration in stimulus selection modulated by the catecholaminergic systems.  相似文献   
172.
This study was a comparison of the effects of oral speech with total communication (speech plus sign language) training on the ability of mentally retarded children to repeat 4-word sentences. Three children were chosen who used single words to communicate but who did not combine words into complete sentences. Three sentence pairs were trained, with each pair having one sentence trained using oral methods and an equivalent one trained using the total communication approach. Both training procedures involved chaining sentence parts, reinforcement, and prompting. Oral methods involved presenting vocal stimuli and requiring vocal responses whereas total communication methods involved presenting vocal and signed stimuli and requiring vocal and signed responses. For the initial sentence pair with each child, an alternating treatments design was used to determine the relative efficacy of the two language training approaches. This was repeated with a second and third sentence pair using a multiprobe technique within a multiple baseline design. Results pointed to the superiority of the total communication approach in facilitating sentence repetition. Possible explanations of these results are offered and the utility of the alternating treatments experimental design is discussed.  相似文献   
173.
We investigated the programming of generalization and maintenance of correspondence between verbal and nonverbal behavior in a preschool setting. Four children participated in a series of multiple-baseline designs. In Experiment 1, delayed reinforcement of verbal behavior effectively controlled maintenance of correspondence with previously trained responses and also resulted in generalization of correspondence to one untrained response. As the latter effect was limited, Experiment 2 was a further assessment of the effects of delayed reinforcement of generalization of correspondence to untrained responses, and consistent generalization was shown. Experiment 2 also showed that generalization, if lost, could be recovered through use of "booster training," in which the original contingencies were reinstated for a brief period. Experiment 3 provided replications, with two additional children, of the effects of delayed reinforcement on maintenance of correspondence. Results are discussed in terms of using delayed reinforcement as an indiscriminable contingency.  相似文献   
174.
175.
Central -peripheral organization of needs in women with eating disorders was investigated. Subjects included three clinical groups, totalling 50 female university students, identified as anorectic, bulimic and obese, and two nonclinical control groups, totalling 70 female students. The revised Picture Identification Test (PIT), which measures motivational aspects of Murray-based needs, was administered to all subjects. A new PIT measure, Cenper Index, showed significant differences in central-peripheral organization of needs between clinical and control groups, and among clinical eating disorder groups. The anorectic group differed most from groups on aggression and succorance needs; the bulimic group differed on abasement and defendance needs; and the obese group differed on dominance, exhibition, and gratitude needs.  相似文献   
176.
Problem-solving processes play an important role within remedial and human effectiveness models of development. This article discusses the use of preventive problem-solving training with college students.  相似文献   
177.
Analysis of two chimpanzees' conversations with their teacher during a tool-use training task demonstrated that chimps use lexigrams, a humanly devised visual symbol system, selectively to encode perceived variability; that is, they generally used their symbols to differentiate alternative possibilities or to represent change or novelty in a situation. In contrast, they tended to leave unsaid what was unchanging, repetitive, or the unique possibility in a situation. Perceived variability influenced not only which symbols were selected but also utterance length: A single dimension of variability in a situation leads to single-lexigram utterances; multiple dimensions are associated with multi-lexigram utterances. This pattern of results indicates that the absence of formal grammatical structure in chimp language does not imply that utterances beyond one word in length are either rote strings or imitations. The chimps' tendency to mention the variable while leaving the constant or redundant unsaid is, moreover, strong support for the position that their use of a humanly devised symbol system is more than a series of conditioned responses.  相似文献   
178.
179.
This paper discusses an exploratory investigation concerned with the long range questions: How does group psychotherapy help patients? and How can psychiatry residency programs best train residents to treat patients in therapeutic groups? Group psychotherapy has come to be accepted in its own right as a decisive contribution to the study of and relief of emotional disorders. As a component of comprehensive psychiatric services it is indispensable. However, while its clinical value has been demonstrated, its scientific validity has not. A Group Process Inventory has been developed by the author and has been utilized for the past two years by psychiatric residents in recording the process of their therapeutic groups in a teaching hospital mental hygiene clinic. The preliminary use of this recording as a clinical-teaching instrument has proven effective. This inventory is being revised to serve as a research instrument.  相似文献   
180.
Suicide and rurality in urban society   总被引:3,自引:0,他引:3  
Recent findings suggest that suicide increases with rurality, but research on rural suicide leaves many questions unanswered. This study specifies problems of community organization as a reason for expecting a positive effect of rurality on the suicide rate. A multiple regression analysis of county data shows that rurality has a substantial positive effect and is, in fact, the best predictor of the suicide rate among several variables selected from the previous literature. Additional research is needed to test the interpretation that rurality contributes to an incomplete, fragmented form of community organization which influences the suicide rate by disrupting primary relationships.  相似文献   
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