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991.
Behavioral conceptions of alcohol abuse often include the hypothesis that drinking behavior is a negatively reinforced operant, with ethanol intoxication viewed as alleviating aversive environmental and internal states. This hypothesis has not been confirmed or refuted by previous studies which employed mild stressors and limited assessment methodology. In the present experiment, 22 patients with severe phobias approached their phobic animal under two consecutive conditions—first while sober and second after drinking either a placebo or an intoxicating dose of ethanol. The severe anxiety induced was assessed behaviorally, physiologically and by the patient's self-report of fear. The intoxicated patients did not experience decreased anxiety, tachycardia or avoidance, compared to the placebo group. These results have clinical implications and suggest the need to reconsider tension-reduction theories of alcohol abuse. 相似文献
992.
Sixteen preschool, first-, and third-grade children were presented with short stories ending with a verbal statement by a story character. Two alternative ending statements were provided. One alternative violated a postulate (H. P. Grice, 1975, in P. Cole & J. Morgan (Eds.), Syntax and Semantics (Vol. 3), New York: Academic Press) or a reasonable request condition (D. Gordon & G. Lakoff, 1971, Conversational postulates, papers from the seventh regional meeting of the Chicago Linguistic Society, University of Chicago, Department of Linguistics), while the other alternative did not. The child's task was to choose the “funny or silly“ ending, i.e., the violation. Data analysis showed that 100% of the third-graders, 83% of the first-graders, and 19% of the preschoolers performed with significant (P < .02) accuracy. These results suggest that children's understanding of conversational principles improves considerably between preschool and first grade. There were no significant differences among four types of conversational principles examined. 相似文献
993.
The effects of flavor preexposure and test interval on conditioned taste aversions were examined in four experiments. In the first three experiments, prior experience with a flavor different from that used as a conditioned-stimulus (CS) produced attenuated aversions when testing occurred after a 1-day interval but not after a 21-day interval. Preexposure to the same stimulus used as a CS produced attenuated aversions at both 1- and 21-day intervals. In Experiment 4, a delay interval between flavor preexposure and conditioning eliminated the attenuating effect of preexposure, but only when different stimuli were used for preexposure and conditioning. These data could not be easily accounted for by contemporary interpretations of preexposure as an event that interferes with subsequent acquisition of a conditioned aversion. An alternative retrieval interference hypothesis was outlined. 相似文献
994.
Elizabeth D. Capaldi 《Learning and motivation》1973,4(2):229-235
The performance of rats trained in a straight alley for 55 trials under 75% body weight and then shifted to 90% body weight was compared to that of rats trained only under 90% body weight. When training was with a small reward the speed of the shifted group decreased to the level of the 90% small reward control groups, but when training was with a large reward the speed of the shifted group dropped below the level of the 90% large reward control group. Thus, the effects on performance of shifting deprivation level following extended training depend on the reward magnitude employed. 相似文献
995.
The roles which word class (open/closed) and sentential stress play in the sentence comprehension processes of both agrammatic (Broca's) aphasics and normal listeners were examined with a word monitoring task. Overall, normal listeners responded more quickly to stressed than to unstressed items, but showed no effect of word class. Aphasics also responded more quickly to stressed than to unstressed materials, but, unlike the normals, responded faster to open than to closed class words regardless of their stress. The results are interpreted as support for the theory that Broca's aphasics lack the functional underlying open/closed class word distinction used in word recognition by normal listeners. 相似文献
996.
997.
998.
Pigeons were tested for generalization along the line-orientation dimension, after being trained on various two-component multiple schedules. The first component contained either a variable-interval 1-min schedule of immediate reinforcement or an extinction schedule and was associated with a plain white key (S1). The second component contained a variable-interval 1-min schedule of delayed reinforcement and was associated with a black line on a white background (S2). The major results showed that (a) decremental gradients were obtained around the stimulus associated with the delayed reinforcement component when S1 was associated with extinction, but that incremental gradients were obtained when S1 was associated with immediate reinforcement, (b) the subjects' pretraining did not affect the generalization gradients if sufficient training on the terminal multiple schedule was provided, and (c) changing the S1 schedule from immediate reinforcement to extinction produced behavioral contrast if reinforcement was delayed for 10 sec during S2, but not if it was delayed for 20 sec. 相似文献
999.
D B Boles 《Brain and language》1985,26(1):106-116
Word recognition typically is better or faster in the right visual field than in the left visual field, an effect that often interacts with the handedness of subjects or the phonetic characteristics of the language employed. While these findings suggest a hemispheric locus, it is possible that the field difference is confounded with display or report order asymmetries. Here two experiments manipulate word orientation (horizontal vs. vertical), letter symmetry, and report order variables, and they demonstrate a generalized right field superiority that fails to interact with other factors. Since the superiority appears even when all apparent artifactual asymmetries are eliminated, the findings support a hemispheric interpretation. 相似文献
1000.
The predictive validity of WISC-R factor scores was examined with samples from the four sociocultural groups of Anglo, Black, Chicano, and native American Papago. The Full Scale IQ and Verbal Comprehension (VC) factor scores were significantly better predictors of achievement as measured by teacher ratings and the Metropolitan Achievement Test. The Perceptual Organization and Freedom from Distractibility (FD) factor scores were also significantly related to achievement, but at a lower level than Full Scale and VC. The correlations of the WISC-R and achievement measures were nearly the same for three of the four groups (exception was native American Papago). The relationship of the FD factor score to ratings of attention was statistically significant, but relatively low. Cautions in interpreting FD as a measure of attention were recommended due to overlap of distributions and low proportion of variance in attention accounted for by FD. 相似文献