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991.
992.
Choice and delay of reinforcement   总被引:32,自引:27,他引:5       下载免费PDF全文
Pigeons were trained to peck either of two response keys for food reinforcement on equated aperiodic schedules. The distribution of responding at the two keys was studied as reinforcement was delayed for various durations. The relative frequency of responding at each key was shown to match the relative immediacy of reinforcement, immediacy defined as the reciprocal of the delay of reinforcement.  相似文献   
993.
The pigeon and the rat partition total response output between both schedules of a concurrent variable-interval pair. The quantitative nature of a partition seems critically dependent on the relative rates with which the two schedules provide reinforcements for responding, in addition to the changeover delay. The manner in which the changeover delay controls the partition was studied by varying the duration of the changeover delay from 0 to 20 sec with each of two pairs of concurrent variable-interval schedules, viz., Conc VI 1.5-min VI 1.5-min and Conc VI 1-min VI 3-min. Rats served as the subjects and brain stimulation was employed as the reinforcer. When the schedules were Conc VI 1.5-min VI 1.5-min, relative response rate approximated 0.50 at all values of the changeover delay. When the schedules were Conc VI 1-min VI 3-min, relative response rate, computed with respect to the VI 1-min schedule, increased when the duration of the changeover delay increased. Changeover rate decreased when the duration of the changeover delay increased. The decrease was the same for both VI schedules of the Conc VI 1.5-min VI 1.5-min pair but was more rapid for the VI 3-min schedule of the Conc VI 1-min VI 3-min pair.  相似文献   
994.
Book reviews     
The Journal of Value Inquiry -  相似文献   
995.
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Zusammenfassung 30 weibliche und 30 männliche Versuchspersonen gaben im Dunkelraum bzw. mit geschlossenen Augen bei seitlicher Körperneigung bis in die Horizontale an, in welcher Position ihnen eine Leuchtlinie und ein Metallstab senkrecht erschienen. In nichtlinearer Abhängigkeit vom Grad der Körperneigung zeigten sich dabei Abweichungen der scheinbaren von der objektiven Vertikalen. Die Tendenz dieser Abweichung war für den visuellen wie für den taktilen Wahrnehmungsbereich gleich, bei geringer Körperneigung entgegen, bei großer Körperneigung in die Richtung der Neigung, wobei letztere Tendenz stärker für die visuelle Vertikale ausgeprägt war. Die Ergebnisse wurden auf dem Boden der sensoritonischen Wahrnehmungstheorie interpretiert, nach der sich die Veränderungen in der Lage der scheinbaren Vertikalen nach dem Prinzip der sensori-tonischen Induktion auf Tonusveränderungen des Organismus durch die Scitwärtsneigung zurückführen lassen. Zur Erklärung der nichtlinearen Beziehung zwischen Körperneigung und Abweichung der scheinbaren Vertikalen wurde ein dynamisches Kräftespiel zwischen einer Tendenz zur Reizzuwendung und einer im Dienst der Konstanterhaltung der Wahrnehmungswelt dieser entgegenwirkenden Reaktion angenommen. Das Ergebnis dieses Kräftespiels ließ sich interpretieren, wenn man die Bedeutung einer Konstanterhaltung der Raumdimensionen in aufrechter gegenüber liegender Körperstellung für den visuellen Fernraum gegenüber dem taktilen Nahraum berücksichtigt.
Summary Thirty male and 30 female Ss indicated by means of a luminescent rod in the darkroom and by means of a metal bar with closed eyes the vertical direction of space under systematic variation of tilt from erect to the horizontal position. Deviations of apparent from true vertical had a non-linear relation to the degree of body tilt. The trend of deviations was similar for the visual and tactual experiment: With small angles of body tilt apparent vertical tended to deviate opposite to the direction of tilt; with large degrees of tilt apparent vertical tended to deviate in the direction of tilt. The latter tendency was more pronounced for visual than for tactual vertical.The results were interpreted in keeping with sensory-tonic field theory of perception, according to which deviations of apparent vertical were due to changes in the sensory-tonic state of the organism. Such changes were experimentally introduced through lateral body tilt. To explain the non-linear relation between deviations of apparent vertical and the degree of body tilt, it was hypothesized that there is a dynamic interplay between a primary tendency of the organism to towards stimulation and a secondary opposing tendency serving the maintenance of constancy of spatial dimensions. The result of this interplay was interpreted by introducing the notion of biological relevance of spatial constancy of the upright position versus the reclining position for visual far-space and tactual near-space.


Diese Arbeit wurde unterstützt durch ein Public Health Service Research Grant, MH-00348 des National Institute of Mental Health, während der erste Autor als NATO-Forschungsstipendiat an der Clark-Universität arbeitete. Die Berechnungen wurden im Rechenzentrum des Massachusetts Institute of Technology, Cambridge, Massachusetts durchgeführt.  相似文献   
999.
The “disjuncture” between level of aspiration and means of accomplishing it can create serious difficulty for the person. The function of the 2-year college in helping the student to resolve this conflict has been described as a “cooling-out” process. Essentially, it involves a running evaluation of the student's capacities, and guidance in helping him to find the educational and vocational program for which he is best suited. Several ways of facilitating this process are presented. There is need for an integrated guidance program pervading the entire institution as well as the student's career at the institution.  相似文献   
1000.
This paper examines the possibility of a closer relationship between the school counselor, the school psychologist, and the school social worker. It describes the background of each of the trio, then describes the various functions and the professional education of counselors, psychologists, and social workers. The various steps that might be taken to inaugurate an “ecumenical movement” between the three professional groups are then discussed. School counselors are described as being the logical individuals to take the initial steps in such a proposed movement, and the new functional title suggested for each of the three is “school counseling psychologist.”  相似文献   
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