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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   
223.
This essay provides guidelines for designing a doctoral program in behavior analysis. First, we propose a general accomplishment for all behavior analytic doctoral students: that they be able to solve problems concerning individual behavior within a range of environments. Second, in order to achieve this goal, we propose that students be trained in conceptual and experimental analysis of behavior, the application of behavioral principles and the administration of behavioral programs. This training should include class work, but it should emphasize the immersion of students in a variety of environments in which they are required to use behavior analytic strategies. Third, we provide an example of a hypothetical graduate program that involves the proposed training. Finally, an evaluation plan is suggested for determining whether a training program is in fact producing students who are generalized problem-solvers. At each step, we justify our point of view from a perspective that combines principles from behavior analysis and educational systems design.  相似文献   
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Sternheim and Boynton’s (1966) continuous judgmental color-naming technique was used to assess the elemental nature of achromatic colors. Results from three subjects indicate that the names “black” and “white” are necessary and sufficient to describe achromatic test lights associated with the name “gray.” On the basis of the criteria that establishes a color as elemental, black and white were confirmed as elemental, whereas gray was not. These findings support the assumption of various opponent processing models that there are only two elemental achromatic sensations. In addition, the results support Hering’s (1920) view that black and white differ from the paired-chromatic opponent colors in that they are not mutually exclusive.  相似文献   
226.
This study sought to identify the higher level knowledge (e.g., conservation of number) necessary for a child to understand linear measurement and to chart the growth of linear measurement in terms of the development of its components. To assess the presence of these components, a battery of 34 number, length, and distance tasks was developed and administered to 100 children between the ages of 63 and 78 months from kindergarten and Grade 1. Results indicate that there is a substantial delay between acquisition of the necessary components and emergence of a mature grasp of linear measurement. The collection of components for the number and length domains form scaled sets; within each domain, however, the pattern of development is marked by discontinuities. These discontinuities are interpreted as being associated with the need to reorganize number and length concepts. Most elements of the observed sequences of development are predicted by Piagetian theory, although others, such as asynchronies between conservation and transitive inferences of nonequivalence, are more consistent with Gagne's (1968) model of development.  相似文献   
227.
This paper deals with imposturous tendencies as ubiquitous and heterogeneous. They may enter into neurotic conflict and compromise, and also reflect an ego function disturbance involving multiple, shifting identities and subsequent problems in the subjective sense of reality of the self and objects. Imposture in a person undergoing analysis is, however, not only a function of individual character and psychopathology; it is also a function of certain inevitable requirements of the analytic situation which constitute a "pull" for its emergence. Vulnerable individuals will respond to this pull in revealing ways. Three case summaries illustrate the spectrum of imposturous tendencies.  相似文献   
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A W Koester  J K May 《Adolescence》1985,20(77):97-113
The purpose of this study was to examine the clothing practices in the daily selection, care, and purchase of clothing by adolescents in order to determine the extent these practices are performed independently or influenced by others, and to identify the factors involved in the activities. Clothing Practice Profiles were developed for both sexes in the three age groups corresponding to divisions in the Oregon 4-H program. The age group comparison revealed increasing frequency of independent activity in all three clothing practice areas (selection, care, and purchase) as age increased. Parental influence appeared to decrease with increasing age. Siblings' influence was minimal. Peer influence on selection and purchase practices increased. Media influence on daily clothing selection practices and clothing purchase practices in terms of wearing or buying identical or similar clothing was minimal. Media influence in advertisements increased with age, but purchases of advertised clothing items remained about the same. Age group comparisons were also made for selection factors and other care and purchase practices, including responsibilities for care of the member's and family's clothing, planning clothing purchases, sources of funds and methods of paying for clothing, use of clothing label information, and purchase factors.  相似文献   
230.
We have become a drug-oriented society. Cummings (1979), citing evidence from the National Institute of Drug Abuse, reports that one of every eleven adult Americans suffers from a severe addictive problem. Drug addition is epidemic among teenagers; one of every six teenagers suffers from a severe addictive problem. This paper focuses on adolescent drug/substance abuse.  相似文献   
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