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921.
922.
923.
Aerobic exercise which resulted in a significant improvement in cardiovascular functioning had no more effect on psychological mood states than did the placebo control of participation in nonaerobic recreational games or no exercise and sport at all (N = 430 college students). Beta-endorphin levels with the 41 depressed subjects were not a biochemical link that might explain the possible influence of physical activity on depression.  相似文献   
924.
The purpose of this study was to gather evidence on the validity of the Vando R-A Scale, a paper-and-pencil measure of perceptual reactance. The Vando R-A Scale and Petrie's kinesthetic aftereffect measure of perceptual reactance were administered to 46 participants drawn from university undergraduates. The Vando R-A Scale was not a valid measure of perceptual reactance. The continued use of the Vando R-A Scale as an alternate measure of perceptual reactance is contraindicated.  相似文献   
925.
For 40 males who smoked 20 cigarettes a day titratable acidity of the urine was significantly correlated with nicotine/cotinine excretion at several sample intervals, as was urinary pH, but not urinary acidity and daily cigarette consumption or serum COHB.  相似文献   
926.
The parallel-lines illusion provides a prototypical example of visual-size assimilation, where the size of a test element is phenomenally skewed towards (or "averaged with") that of a context element. Most assimilation theories predict that distortion should decrease with spatial separation between context and test lengths. However, there is some disagreement about the nature of the function relating sizes of context and test elements and magnitude of assimilation. The present study tests the limits of assimilation in the parallel-lines configurations by observing the effects of a wide range of context/test size ratios, repeated over two disparate levels of spatial separation. The results replicate and extend 1979 findings by Brigell and Uhlarik, confirming that assimilation rises to a peak at midrange size ratios, only to decrease continuously as the ratios become more extreme. The functions were nonmonotonic and similar in shape for both levels of spatial separation, with an over-all decrease in distortion for configurations with the larger separation.  相似文献   
927.
6 adult subjects (3 men, 3 women) produced highly similar spontaneous speech utterances in quiet and with 90-dB SPL white noise. The frequency of occurrence of perceptual judgments of primary stressing in an utterance was not affected by the masking noise. This finding supplements our previous report that variability for stress production of fundamental frequency (fo) during spontaneous speech was preserved under short-term auditory disruption. Also, it adds further support to the contention that fo is under open-loop regulation.  相似文献   
928.
929.
Context-dependent effects on analogical transfer   总被引:1,自引:0,他引:1  
The role of context in facilitating analogical transfer was investigated in two experiments. In both experiments, subjects first read two stories that were analogous to Duncker’s (1945) radiation problem. Later, subjects attempted to solve the radiation problem. In Experiment 1, the radiation problem was presented in a different context than that of the stories, and followed them by 6 min. Transfer was observed in subjects who were prompted to use the earlier stories in solving the problem. However, the solution frequency of subjects not given such prompts did not differ from control levels. In Experiment 2, the radiation problem was presented in the same context as the earlier stories to some subjects, and in a different context to others. The timing of the radiation problem also was varied. When a 6-min interval separated the stories from the radiation problem, transfer was a function of context, with weak transfer being observed in the samecontext condition, and no transfer being observed in the different-context condition. At a 45-sec delay, transfer was again observed in the same~ontext condition, and a nonsignificant trend toward transfer was observed in the different-context condition. The results were interpreted as indicating that context facilitates the retrieval of relevant problem-solving schemas, and as suggesting that the possession of relevant schemas is not sufficient to produce analogical transfer.  相似文献   
930.
The lexical decision task has been employed to investigate the effects of semantic context on word recognition. A frequent finding from the task is that “word” responses are slower when the target is preceded by an unrelated word than when it is preceded by a neutral stimulus. This inhibition effect has been interpreted as indicating that the unrelated prime interferes with word-recognition processes operating on the target. In three experiments, the effects of unrelated primes were compared for a lexical decision and word naming task. Although large inhibition effects were found for the lexical decision task in all experiments, no inhibition effects were observed for the naming task. The results are interpreted as demonstrating that inhibition effects in the lexical decision task are not on recognition processes; rather they are located at processes operating after recognition of the target has occurred.  相似文献   
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