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871.
Effects of component length and of the transitions among components in multiple schedules 总被引:4,自引:4,他引:0 下载免费PDF全文
Hinson JM Malone JC McNally KA Rowe DW 《Journal of the experimental analysis of behavior》1978,29(1):3-16
Pigeons received equal variable-interval reinforcement during presentations of two line-orientation stimuli while five other orientations appeared in extinction. Component duration was 30 seconds for all orientations and the sequence was arranged so that each orientation preceded itself and each other orientation equally often. The duration of one component (0°) was shortened to 10 seconds and the other (90°) was lengthened to 50 seconds. All animals showed large increases in response rate in the shortened component and this increase was recoverable after an interpolated condition in which all components were again 30 seconds in duration. This effect was replicated in a second experiment in which component duration was changed from 150 seconds to 50 seconds and 250 seconds. An examination of local contrast effects during the first experiment showed that the shortened component produced local contrast during subsequent presentations of the lengthened component, just as would a component associated with more frequent reinforcement. When the presentation sequence was changed so that the lengthened component was always followed by the shortened component, response rates generally increased during the lengthened component. When the sequence was arranged so that the shortened component always preceded the longer component, response rate decreased in the former. These effects, as well as the increases in response rate following change in component length, seem not to be the product of local contrast effects among components. 相似文献
872.
Delayed reinforcement of fixed-ratio performance without mediating exteroceptive conditioned reinforcement 下载免费PDF全文
The performance of pigeons was studied under conditions in which the completion of a fixed-ratio requirement was not contiguous with the presentation of a reinforcer. Timein and timeout periods alternated throughout the experimental sessions. Responses made by an experimental bird during the timein period were accumulated, and when a fixed-ratio requirement had been met, grain was presented to the experimental bird and a yoked control following their first response in the next timein period. Across most manipulations of the fixed-ratio requirement and of the duration of the timeout period, the response rates of the experimental birds were considerably higher than those of their controls, suggesting that the response-reinforcer dependency controlled the behavior of the experimental bird in the absence of a close temporal association between responding on the ratio schedule and reinforcer presentations. 相似文献
873.
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
874.
The effects of subliminal stimulation on masculinity-femininity ratings of a male model were tested for 100 male undergraduates, randomly divided into four groups and individually shown a slide of a male model. One group received no further stimulation. A second group received a subliminal flash of white light across the image of the model; a third group was presented with the subliminal message "masculine," while a fourth group was presented with the subliminal message "feminine." Subjects were asked to rate the model on a six-point scale of masculinity-femininity. The differences in ratings among groups were not significant, indicating that subliminal stimulation did not influence masculinity-femininity value-norm-anchor judgments. There were no significant differences in the reported perception of additional stimuli or the tendency to be relaxed among the four groups. However, subjects who received the "masculine" message and reported that they were more relaxed did tend to rate the model higher in masculinity. 相似文献
875.
E W Kelly 《Perceptual and motor skills》1978,46(2):627-632
This study investigated the effects of amount and direction of eye contact with the counselor on a student's perceptions. 48 undergraduate and graduate education majors were randomly assigned to one of six conditions in a 2 x 3 factorial design representing two levels of eye direction (eye-to-eye and eye-to-nose/mouth) and three amounts of eye contact (high = 85%, medium = 50%, low = 15%). Subjects had 10-min. standard interviews that differed only according to the six experimental conditions. Interviews were videotaped to assess maintenance of experimental conditons. Following the interview, subjects rated (5-high to 1-low) the interview on seven variables (comfort, attention, interest, ease, helpfulness, eye contact, and willingness to return). Interrater reliability for maintenance of experimental conditions was .87 on amount of eye contact and .03 for direction. Scheffé comparisons showed high and medium eye contact produced significantly higher ratings by student clients on attention, interest, eye contact, and willingness to return than low eye contact. There were no differences for direction of eye contact. 相似文献
876.
Preference for stimulus complexity across the life-span was investigated with 175 females ranging in age from 17 to 72 yr. of age. Preference for complexity appeared to be age-invariant and monotonic function. Relationships to previous findings are discussed. 相似文献
877.
G E Kühne J U Grünes W Knorr L Perina H Richter U Rommel R Sorger H St?ck N Waldow 《Psychiatrie, Neurologie, und medizinische Psychologie》1978,30(2):104-115
The antidepressants desipramine and imipramine were compared within the framework of a multiclinical study performed under the conditions of a controlled clinical experiment. There has been found a time-different remission of affective symptoms, which was not detectable for the inhibition of drive. The tachythymoleptic action of desipramine is discussed with reference to these results. Evaluation of the possibility of controlling affects shows different ranges of activity of desipramine and imipramine, with desipramine influencing especially negative psychoenergetic symptoms in the area of drives and emotions and imipramine, restrictive symptoms in addition to differential phenomena of the psychomotor expression. 相似文献
878.
A serial visual afterimage (AI) test was administered to 136 normal and 75 anxiety-ridden children 4–16 years of age. The scoring of the AI serials involved signs of primitive functioning (size-constant and positive AIs), anxiety (large and dark AIs together with primitive AIs in older children) and process discontinuity (intermittent regressions to small, positive, or physiognomic AIs). Differences between normal and clinical children were generally highly significant in these respects. Special attention was directed to the difference between subjects with intermittent regressions to primitive functioning and subjects where regression represented a lasting functional alternative. The former subjects were more often characterized by paroxysmal or primary anxiety. 相似文献
879.
880.