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191.
A reversal-shift paradigm was used to study the effects of dimensional labeling on the performance of 270 kindergarten children. Task 1 was a simultaneous discrimination problem in which form, size, and color were redundant relevant dimensions, In the shift task, one of the dimensions remained relevant with reward contingencies reversed, and the other two dimensions were made irrelevant. In both tasks, the children named the stimulus object to be chosen, prior to choosing, in terms of one of the three sets of dimensionnal values. Shift performance was predicted to be superior in groups required to name relevant dimensional values in comparison with groups required to name irrelevant dimensional values. Moreover shift performance was predicted to differ, within groups, for four different types of stimulus settings. Fmally, differences in performance on the settings were predicted to be larger for the irrelevant-labeling groups than for the relevant-labelmg groups. The results were found to be in good agreement with these predictions. The findings were discussed in relation to the subproblem analysis proposed by Tighe and Tighe (1972).  相似文献   
192.
Eight volunteers maintained on daily methadone participated in a classical conditioning procedure to determine which if any of the elements of narcotic withdrawal could be conditioned. The unconditioned stimulus was the injection of a small dose of naloxone. The unconditioned response was a brief precipitated withdrawal syndrome. The conditioning stimulus was a tone, odor, and injection of saline. Conditioning was successful in the pilot study in 5 of 8 subjects. The conditioned response consisted of tearing, yawning, lacrimation, systolic blood pressure increase, respiratory irregularities and subjective feelings of narcotic withdrawal sickness (nausea, muscle aches, chills). A second group of 8 subjects showed, in addition to the above, evidence of conditioning of heart rate, respiratory rate and skin temperature decrease. These laboratory findings support the clinical reports of a conditioned withdrawal syndrome and suggest ways to improve treatment results by detecting and extinguishing or modifying conditioned responses.  相似文献   
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Sixteen observers palpated silicone models of human breasts containing lumps 1.6-12.1 mm in diameter. Detectability depended on the size of the lump, producing a systematic psychometric function. In eight observers who participated in three or more sessions, performance improved with practice, with most improvement occurring within one or two 26-trial sessions. Three-week retention measures disclosed no appreciable decrease in performance, but a significant correlation was found between the number of lumps detected and duration of trial (p < .01). There was no difference in performance between four observers who used their preferred hands and four observers who used their nonpreferred hands. These data establish that examination of breast models for the detection of lumps simulating cancer is a task amenable to experimental analysis.  相似文献   
194.
It was suggested that thought changes cognitions to be more consistent with one's initial attitude direction and, therefore, results in attitude polarization. Specifically, it was predicted that polarization would be highest under thought with reality constraints absent, followed by thought with reality constraints present, followed by distration. During the first period of each of two trials, some of the 144 subjects were distracted from thinking about a preselected painting, others thought about the painting while viewing it, and others thought about it in its absence. Subjects were redistributed across the same three conditions for a second period. They then indicated their feelings about the painting. In the original study as well as a partial replication, females behaved as predicted: Thought with reality constraints absent produced the most polarization, followed by thought with reality constraints present, followed by distraction. In both the original study and the replication there was no systematic trend for the males. The theoretical implications of the female results and the sex differences were discussed.  相似文献   
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Beliefs concerning the spread of the human immunodeficiency virus (HIV) and preventive behaviors were examined in a sample of 351 sexually active Scottish teenagers. A postal questionnaire, including measures of variables specified by the health belief model (HBM) and preventive intentions, was employed. The relation between HBM measures and reported endorsement of HIV-preventive intentions was investigated. Results indicated that, in general, respondents intended to use condoms with new sexual partners. The majority also intended to carry condoms if they thought they might have sex with a new partner and to ask potential partners about their previous sexual history. Multiple-regression analyses showed that measures of health beliefs, gender, age, sexual experience, and previous condom use accounted for 17.8% to 24.3% of the variance in reported preventive intentions. Perceived barriers to preventive behaviors were found to be important predictors. However, the overall pattern of results raised questions concerning the adequacy of the HBM as a model of the determinants of HIV-preventive intentions, and the need for an extended model is discussed. Separate analyses were conducted for men and women and for 16- and 18-year-olds, and the implications for modeling intention formation in these subgroups are considered. The relevance of these findings to HIV-preventive campaigns is also discussed.  相似文献   
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