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Rats received Pavlovian conditioning in which food was signalled by a visual stimulus, A+, an auditory stimulus, B+, and a compound composed of different visual and auditory stimuli, CD+. Test trials were then given with the compound AB. Experiments 1 and 2A revealed stronger responding during AB than during CD. In Experiment 2B, there was no evidence of a summation of responding during AB when A+ B+ training was conducted in the absence of CD+ trials. A further failure to observe abnormally strong responding during ABwas found in Experiment 3 for which the training trials with A+ B+ CD+ were accompanied by trials in which C and D were separately paired with food. The results are explained in terms of a configural theory of conditioning, which assumes that responding during a compound is determined by generalization from its components, as well as from other compounds to which it is similar.  相似文献   
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Adult-child interactions during stressful medical procedures were investigated in 43 pediatric patients videotaped during a venipuncture procedure in the course of cancer treatment. Relations among six adult behavior categories (explain, distract, command to engage in coping behavior, give control to the child, praise, and criticize/threat/bargain) and three child behavior categories (momentary distress, cry/scream, and cope) were examined using correlational and sequential analysis. Results indicated that adult distraction resulted in increased child coping and reduced momentary distress and crying. Adult explanations, although a likely response to child distress and crying, did not result in a reduction of these behaviors. Attempts to give the child control reduced child crying. Implications for clinical interventions during painful medical procedures are discussed.  相似文献   
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Ten untreated patients with recently diagnosed Parkinson's disease (PD), 9 treated patients with more advanced pathology, and 17 matched normal controls were investigated with three reaction tasks with increasing cognitive load but identical motor requirements: simple reaction, choice reaction with indicative stimuli, and choice reaction with ambiguous stimuli. Times required until a home key was released (= reaction time) and from then until a response key was pressed (= movement time) were recorded. Estimates of pure decision time (overall response time minus movement time in a simple reaction time task) revealed a difference between advanced and early PD patients. Advanced PD patients showed an overall slowing of decision time in the reaction time tasks, but the effect of the cognitive load of the tasks on the decision time was comparable to a control group. The untreated early PD patients performed quite normally in the more simple decision tasks but showed a disproportionate slowing of decision time in tasks with higher cognitive load.  相似文献   
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