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71.
Criteria for distinguishing between attitude and response scale effects in “after-only” studies of source-recipient discrepancy were developed and applied in two experiments. These criteria refer to congeneric scales (i.e., multiple measures of the the same property, which may differ in origin, unit, and reliability). Persuasive information may function as a scale anchor, in which case it is expected to affect only that response scale to which it directly pertains. Alternatively, it may convice recipients to change attitudinal positions, and produce effects on all congeneric scales. In one experiment, the self-proclaimed leniency-sternness of a presiding judge in a manslaughter case was varied along with the sentence he imposed and his trustworthiness. In the second study, only the sentence was manipulated, while both leniency ratings and sentencing were measured as dependent variables. Both analyses revealed support for the response scale interpretation, in that effects were observed only on those scales that were directly manipulated.  相似文献   
72.
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   
73.
Reaction times of pigeons on a wavelength discrimination task   总被引:5,自引:5,他引:0       下载免费PDF全文
After extensive pretraining, three pigeons were exposed in 2-second trials to a random series of 14 light wavelengths, ranging in one nanometer (nm) steps from 575 nanometers to 589 nanometers. Responses to one of the wavelengths, 582 nanometers, were intermittently reinforced. The relative frequency of response approached 1.0 at 582 nanometers, and decreased with progressively higher and lower wavelengths. Reaction times shorter than about 0.2 second occurred with a low frequency that was largely independent of wavelength. Wavelength controlled the frequency of longer reaction times, but did not affect the distribution of these reaction times. Consequently, receiver-operating characteristic curves constructed by using reaction time as a rating measure did not conform to the signal-detection model, in contrast to such conformity when response rate is used in a similar way. The data suggest that stimulus onset as such triggers early response emission with some small probability; the probability of responses with longer latency is controlled by wavelength, but their time of emission is controlled by some independent process.  相似文献   
74.
Behavioral contrast as differential time allocation   总被引:5,自引:5,他引:0       下载免费PDF全文
In Experiment I, hooded rats were exposed to multiple variable-interval schedules of reinforcement in which manipulanda and reinforcement magazines at opposite ends of the experimental chamber were associated with the different components. Time allocated to each component was measured by recording the time spent by the subject in the appropriate half of the chamber. Positive behavioral contrast was observed for the comparison between multiple variable-interval 30-second variable-interval 30-second and multiple variable-interval 30-second variable-interval 90-second conditions for both response frequency and time allocation measures, but not for mean local response rate (response frequency per time allocated to a component). In Experiment II, rats were exposed to multiple variable-time schedules in which reinforcement was response independent. Time allocated to each component was measured for two conditions, multiple variable-time 30-second variable-time 30-second and multiple variable-time 30-second variable-time 90-second. Positive behavioral contrast of time allocation was exhibited. The results indicated that time allocation was differentially sensitive to changes in reinforcement probability, and that behavioral contrast may result from the differential allocation of time to the different components of the multiple schedule.  相似文献   
75.
The hypothesis that mentally retarded persons have a short-term memory deficit whixh is due to inadequate rehearsal strategies is reexamined. A reevaluation of results of a number of experiments suggests that normal and retarded persons differ on short-term memory tasks, and the superiority of normals is present from the time of initial stimulus exposure. While some evidence for slope differences in retention curves is found in a few tasks, it is not strong support for memory differences. The hypothesis that “memory” differences are due to differential encoding as a result of more adequate rehearsal by the normal subjects is unacceptable. If this were the case, some differences in slope of retention curves could be expected unless rehearsal beyond the encoding stage was totally precluded. The review points to a need for an empirical reevaluation of the issue with a full recognition that deficits in particular processes may characterize some retarded persons and not others.  相似文献   
76.
Consequences for a new target as a function of noncooperation was investigated in the instigative aggression paradigm. Subjects instigated partners to aggress against an opponent by suggesting what shock intensity to deliver. The partner was either cooperative (i.e., complied with the suggestion) or noncooperative (i.e., refused to set high shocks). Subsequently, subjects were given the opportunity to be directly aggressive by actually setting the shocks themselves. During this phase a new target who was nonprovocative was introduced. Subjects aggressed alone, in the presence of their partner, or in the presence of a new person. Results revealed that noncooperation reduced the level of instigative aggression and carried over to the second phase of the experiment. Subjects who had had cooperative partners were more aggressive toward the new target than were subjects who had had noncooperative partners. The presence or absence of the partner was not significant.  相似文献   
77.
Principal-components analysis was performed on a set of averaged evoked potentials in order to extract components of cerebral activity functionally related to hemisphere, handedness, processing task, and stimulus feature variables. Eight such components were isolated. Degree of dextrality, hemispheric differences, and cognitive operations in processing distinct stimulus characteristics were identified as reflected in functionally distinct components of brain activity.  相似文献   
78.
The attention demands of initiating and controlling discrete movements were examined as a function of their movement time (MT) and average movement velocity. Experiment 1 showed that the attention required to execute a movement decreased as MT decreased, although Experiment 2 through independently manipulating MT and movement velocity, revealed that movement velocity is the key determiner of attention demands rather than MT. The attention demands of preparing a high velocity movement are greater than during its execution with the reverse being the case for relatively slow velocity movements. The results are compatible with the view that it is the initiation of error corrections that are attention demanding (Keele 1973).  相似文献   
79.
Three experiments were intended to examine the relationship between alcohol, depression and learned helplessness. In Study I, more female undergraduate heavy drinkers than light drinkers were found to have critically elevated scores on a depression index. A sex difference in the relationship between drinking and depression is suggested since male depressives were equally distributed among drinking categories. In Studies II and III, female undergraduates were given unsolvable problems in a learned helplessness paradigm. Relative to controls these subjects reported increased depressive and hostile affect and drank more beer in a taste rating task. However, we failed to find deficits in anagram solution with those subjects given the learned helplessness manipulation. Specific questions are raised regarding the boundary conditions of learned helplessness while implications bearing on stress-related alcohol consumption are discussed.  相似文献   
80.
It is difficult to gain unambiguous evidence on the use of concepts by infants. Many results can be accounted for in terms of action-based strategies. The evidence reported here fulfils the minimal criteria for the operation of working concepts in infants. Search tasks are used with a filled interval which forces memory-search, and the object is hidden in containers which fulfil their customary job or violate it. Infants treat an upright cup as a more reliable location marker than an inverted one. A series of experiments probes the phenomenon. The results indicate that the infants have a working concept of containment which can be triggered by the provision of containers in their canonical orientation. Even “object permanence tasks” lead infants to access their knowledge of the relationships into which things typically enter in the world outside the laboratory.  相似文献   
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