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311.
The KIM-1 microprocessor combined with a plug-board interface provides an inexpensive and highly flexible system for controlling classical conditioning of the rabbit’s nictitating membrane response. The system is described in the context of a program for differential conditioning.  相似文献   
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Performance was measured in a detection task over a period of 50 min. Subjects were either non-smokers or smoked more than 15 cigarettes per day. No smoking was allowed during the task, but smokers were all asked to smoke a cigarette immediately before doing it. One hour previously, subjects had been given a double-blind dose of a substance which would shift the pH of their urine either upwards or downwards, by small amounts sufficient to affect the rate of renal excretion of nicotine in the smokers. The pH manipulation had no effect on the performance of the non-smokers, who improved steadily throughout the task. After some 40 min of performance, the deprived smokers showed less improvement than the non-smokers, and the smokers whose urine had been made acid improved less than those whose had been made alkaline. The results are interpreted as evidence for a phasic effect on performance of small degrees of nicotine deprivation, which has consequences for theories of nicotine dependence.  相似文献   
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A group of young children (mean age: 2.5 yr) were instructed to follow different requests by a teacher in a day-care setting. Experiment I verified that mean group instruction following was low (10%) despite the opportunity for “observational learning”, i.e., the group of 12 children could watch a nonreinforced adult comply with the teacher's request. In Experiment II, when positive consequences were provided contingent on the adult model's behavior, mean group instruction following was relatively unaffected (14%). When direct reinforcement was given to four peer models, each for several sessions, the individual performances of three of the four peer models was elevated (from 50% to 80%); however, the mean performance of the remaining nonreinforced children (N = 7) was only moderately affected (21%). When reinforcement contingencies were again changed, so that each group member was provided direct, but intermittent reinforcement, mean group performance increased substantially to levels of over 70%. Once instruction following was high, presentation of reinforcement only to one peer model sufficed to maintain performance whereas earlier, this same vicarious reinforcement procedure had failed to establish group compliance. The maintenance of instruction-following behavior when reinforcement was applied solely to one child was interpreted mainly in terms of a high resistance to extinction following a history of intermittent reinforcement rather than a “vicarious”- or “self”-reinforcement mechanism. Finally, removal and re-introduction of group intermittent reinforcement, respectively, lowered performance (to levels of 40%) and elevated (to levels of 65%) the group's performance.  相似文献   
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We examined individual differences in preferences for intrinsic versus extrinsic aspects of work among two representative national samples of males from the Ohio State University National Longitudinal Surveys: young men, aged 14 to 24, and middle-aged men, aged 45 to 59, when first interviewed in 1966. The statistical technique utilized to measure systematic preference differences was Multiple Classification Analysis, a nonlinear form of multiple regression analysis. Findings suggest that preferences are significantly related to age, occupation, class of worker, job satisfaction, educational attainment, and race. After simultaneously controlling for all explanatory variables, very little consistent evidence of preference differences was found between white-collar and blue-collar workers, rural and urban workers, or among individuals with different levels of income.  相似文献   
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This study investigated the differential effect of delayed auditory feedback (DAF) upon general (e.g., repetitions) and specific (e.g., repetitions of initial, medial, and final syllables) overt types of dysfluent behaviors. Ten moderate to severe stutterers performed an oral reading task under both NDAF and DAF (200 msec). DAF resulted in a significant increase in the total number of dysfluencies but had a differential effect upon certain general and specific behaviors. Blocks decreased significantly, prolongations increased significantly, and repetitions and interjections did not change significantly in frequency of occurence. To a limited extent, DAF had a differential effect on specific behaviors. All specific prolongation behaviors increased significantly while only one specific block behavior (ddelays in starting words) decreased. The authors discuss these results in terms of the vocal changes that occurred under DAF and speculate as to their importance in establishing fluency. DAF is viewed as promoting prolongations and prolongations are viewed as inhibiting excessive stoppages of the breathstream, thus promoting fluency (e.g., delays in starting words).  相似文献   
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Studied attitude change following counter-attitudinal advocacy where there was little incentive for subject compliance in an attempt to compare dissonance and self-perception theory predictions. The extent of attitude change was determined either by self-report or by having subjects predict their own true attitudes purportedly monitored by the experimenter using a ‘bogus pipeline’. Forty-eight male and female subjects, students from an introductory Psychology course, were invited to take part in a study of Current Campus Issues. They wrote a short statement that argued against an issue for which they had previously held a positive attitude. Results indicate that there was a significant attitude change in both conditions (p < .003). Attitude change under these circumstances is more successfully explained by the self-perception theory than dissonance theory.  相似文献   
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