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931.
Ablation of inferior temporal cortex in the rhesus monkey produces a visual discrimination learning deficit. The severity of this deficit has often been found to be a function of task difficulty. This report concerns a type of visual discrimination problem that, although difficult, is not sensitive to inferior temporal lesions. Monkeys with anterior, posterior, and complete inferior temporal lesions were repeatedly unimpaired or only slightly impaired in learning to discriminate a pattern from the same pattern rotated 90 degrees or 180 degrees; yet they were very severely impaired in learning equally or more difficult discriminations of two different patterns. This demonstration that discrimination of orientation of patterns is relatively spared after inferior temporal lesions helps specify the pattern-recognition processes that require inferior temporal cortex.  相似文献   
932.
The development of children's dimensional coordination was investigated using kindergarten, second, fourth, and sixth grade subjects (Ages 5, 7, 9, and 11 years, respectively), and an adult sample, by means of a perceptual estimation task requiring the subjects to match in total area a stimulus rectangle to an adjustable square stimulus. The problem was formulated using information integration theory, and the procedures and techniques of functional measurement were used in the analysis. Dimensional coordination was found to develop from a stage of total centration on one dimension to a stage of total decentration with equal weighting applied to both dimensions.Contrary to extant hypotheses, the vertical dimension was not the salient dimension for single dimension centerers. Rather, the spatial axis on which the compared-objects were placed determined the displacement of attention. When this frame of reference effect was controlled, the longer of the two dimensions was the salient dimension for centering subjects.  相似文献   
933.
In an attempt to reconcile conflicting results concerning the effects of sexual arousal on interpersonal evaluations, hypotheses based on adaptation level, arousal-need gratification, and labeling of arousal explanations were tested. The variables of sexual arousal, technique of stimulus material presentation, physical attractiveness of the original stimulus female, and physical attractiveness of the final target person being judged were manipulated in a 2 × 2 × 2 × 2 design. A significant three-way interaction (Arousal × Stimulus Attractiveness × Target Attractiveness) obtained on all measures of interpersonal evaluation was interpreted as supporting a labeling of arousal explanation. It is suggested that subjects first interpret their arousal as being caused by their attraction toward the stimulus person. The characteristics of the stimulus person then become a factor used by subjects when they subsequently make judgments of target females. The adaptation-level and arousal-need gratification hypotheses were not supported.  相似文献   
934.
The Diana (Diana v. State Board of Education, Note 1) and the Larry P. (Larry P. v. Riles, Note 2) litigations led to decertification of thousands of California EMR students and their return to the regular program. Allegations, including those of biased testing, went largely uncontested in order that change in special education could result from court mandate, but the allegations left the psychologists in a libeled state. A study of cumulative records and psychologists files in 12 representative districts permitted a comparison of the EMR placement of those later decertified (D) with matched nondecertified (EMR). Other than a small mean difference in IQ at placement, nothing was found to support various allegations. Records showed no systematic differences betweeen D and EMR groups in pre-EMR reasons for referral nor in teacher marks, discnfirming beliefs in referral of higher functioning students for deportment rather than for academic failure. Districts permitted a mean of at least two years in regular placement before assessment, attesting to class failure rather than IQ as the initial and necessary basis for EMR identification (no D-EMR difference in this either). The data permit a conclusion that the work of the school psychologists in the EMR placement was professionally competent, given the guidelines in effect at the time.  相似文献   
935.
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   
936.
937.
Temporal control of behavior: schedule interactions   总被引:1,自引:1,他引:0       下载免费PDF全文
In Experiment I the response that terminated the postreinforcement pauses occurring under a fixed-interval 60-second schedule was reinforced, if the pause duration exceeded 30 seconds. The percentage of such pauses, rather than increasing, decreased. There were complex effects on the discriminative control of the pause by the reinforcer terminating the previous fixed interval, depending on whether the fixed interval and the added reinforcer were the same or different. In Experiments II(a) and II(b), each reinforcement initiated an alternative fixed-interval interresponse-time-greater-than-t-sec schedule, the schedule values being systematically varied. When the response following a pause exceeding a given duration was reinforced, fewer such pauses occurred than when they were not reinforced, i.e., on the comparable simple fixed-interval schedule. There was no systematic relationship between mean interrinforcement interval and duration of the postreinforcement pause. The pause duration initiated by reinforcement was directly related to the dependency controlling the shortest pause at that time, regardless of changes in mean interreinforcement interval.  相似文献   
938.
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   
939.
Summary That negative precepts play the critical role in the generalization principle is a consequence of the relationship of negative to affirmative precepts, i.e. that the negative give the essential negative condition for observing the affirmative precept. This relationship in turn is based on the nature of: 1) the negative precept which obliges to inaction and consequently demands action in order to violate it; 2) the affirmative precept which obliges to action and can be violated by inaction. Since action requires agency, and agency involves more responsibility than does the non-agency present in violating affirmative percepts, we conclude that violating negative precepts demands more responsibility and consequently that they oblige more than do affirmative precepts. To emphasize this critical role of agency I shall conclude with an example proposed by Michael Tooley: Imagine a machine which contains two children, John and Mary. If one pushes a button, John will be killed, but Mary will emerge unharmed. If one does not push the button, John will emerge unharmed, but Mary will be killed. In the first case one kills John, while in the second case one merely lets Mary die. Does one seriously wish to say that the action of intentionally refraining from pushing the button is morally preferable to the action of pushing it, even though exactly one person will perish in either case?20 Tooley's judgment on this example indicates that the outcome - in either case one person will perish - is the sole moral determinant (intentions do not enter this case) and that agency of pushing the button is of no moral significance. Yet, if you, the reader, stood before this machine and tried to decide what you should do, the fact of your agency in pushing the button would control your decision. Consider pushing the button. What reason could you have for that action? That otherwise Mary would die. But who can say that Mary's life is more valuable than John's? That Mary will die is no valid reason for pushing the button. But what of saving Mary's life? You can't do that without yourself actively killing John. But if you don't, Mary will die. This is true, but she will not die from your agency, and this is critical to your choice. What a machine may or may not do may or may not be under your control. What you do is under your control, and you may not do evil, not even that good may come of it. Consequently, you would be forced to say: the decision of intentionally refraining from pushing the button is morally preferable to the action of pushing it even though exactly one person perishes in either case.  相似文献   
940.
7 subjects, aged 19 to 25 yr., who evoked syntactic verbal material in the report made after awakening during REM sleep, were asked to reproduce it a few minutes later. No big differences had been obsered between the two recalls; all recalled verbal materials, many sentences and kernel-sentences reappeared. These results indicate a good consolidation of the material obtained after awakening during REM sleep.  相似文献   
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