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981.
982.
Two experiments investigated visual attention in human infants. In one experiment, babies looked longer at more than at less saturated colors. In a second experiment, babies looked longer at gratings aligned along the horizontal and vertical orthogonals than along the obliques. Because saturated colors and orthogonal stimulation elicit greater activity in visual system neurons and greater amplitude evoked potentials than desaturated colors or oblique stimulation, these two experiments support the hypothesis that the simple visual stimuli to which infants preferably attend are those that are particularly appropriate in stimulating the geniculostriate or primary visual system. The ethological significance of this taxic mechanism and its utility and function in perception, cognition, and aesthetics are underscored.  相似文献   
983.
A study was conducted to examine the relation between each of several attitudinal qualities and attitude-behavior consistency. Subjects' attitudes toward volunterring to participate in psychological research were assessed. The number of experiments in which each subject volunteered to participate was employed as the measure of behavior. Attitude-behavior consistency was significantly related to (1) the amount of direct experience upon which the subject's attitude was based (specifically, the number of experiments in which the subject had previously participated), (2) the degree of certainty with which the attitude was held, and (3) how well-defined the subject's attitude was, as measured by the width of his latitude of rejection. These three attitudinal qualities were significantly intercorrelated, suggesting that direct experience with an attitude object may produce an attitude that is both better defined and more confidently held than an attitude formed through more indirect means.  相似文献   
984.
Four groups of three subjects resided for 10 days within a continuously programmed environment. Subjects followed a behavioral program of contingently scheduled activities that determined individual and social behaviors. A triadic condition was in effect when all three subjects were required to select simultaneous access to a group area before it became available for a social episode. A dyadic condition was in effect when access to a group area was permitted to any combination of two, and only two, subjects. The effects of these two conditions on individual and social behaviors were studied in reversal designs with several successive days devoted to each condition. Results showed that durations of social activities and synchronization of individual activities were greater during triadic conditions than during dyadic conditions. Under both conditions, wake-sleep cycles departed from a typical day-night rhythm for most subjects. Instances when subjects did not respond to each others' attempts to initiate conversations using the intercom were generally more frequent during dyadic than triadic conditions. Physical distance during triadic social episodes was found to be related to sociability levels during dyadic conditions.  相似文献   
985.
A molar theory of reinforcement schedules   总被引:16,自引:16,他引:0       下载免费PDF全文
Behavior of subjects exposed to concurrent and individual interval and ratio schedules of reinforcement may be described in terms of a set of expressions relating the value of responses to their durations, a feedback equation relating reinforcement to response duration, and the assumption that subjects allocate their time among various responses so as to maximize value.  相似文献   
986.
987.
988.
Pranayama is a Yogic breathing practice which is known experientially to produce a profound calming effect on the mind. In an experiment designed to determine whether the mental effects of this practice were accompanied by changes in the arterial blood gases, arterial blood was drawn from 10 trained individuals prior to and immediately after Pranayama practice. No significance changes in arterial blood gases were noted after Pranayama. A neural mechanism for the mental effects of this practice is proposed.  相似文献   
989.
990.
Two hundred and forty-five working level scientists and engineers participated in a longitudinal study in which their managers had been trained in a Management by Objectives program. Subjects completed two questionnaries, the latter being completed 21 months after the first designed to assess perceptions of their managers' goal setting behavior along four dimensions derived using factor analytic procedures (Goal Clarity and Planning, Subordinate Freedom, Feedback and Evaluation, Participation in Goal Setting) and their reported intrinsic, extrinsic and total satisfaction. Dynamic correlations (Vroom, 1966) were computed between changes in the goal setting factors and changes in the satisfaction variables and significant positive relationships were observed. In addition, results indicated that job task (research vs. development) demonstrated a moderating influence on the goal setting-satisfaction relationships. An unexpected finding was that there was a significant decrease in perceived managerial behavior on the Goal Clarity and Planning factor over the 21 months. However, a significant increase occurred on the Feedback and Evaluation factor. Since no control group was available for comparison, little can be said about whether these changes were a result of the MBO program. Significant differences between the development and the research subjects were also observed on two of the goal setting factors.  相似文献   
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