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991.
Phoneme monitoring and word monitoring are two experimental tasks that have frequently been used to assess the processing of fluent speech. Each task is purported to provide an “online” measure of the comprehension process, and each requires listeners to pay conscious attention to some aspect or property of the sound structure of the speech signal. The present study is primarily a methodological one directed at the following question: Does the allocation of processing resources for conscious analysis of the sound structure of the speech signal affect ongoing comprehension processes or the ultimate level of understanding achieved for the content of the linguistic message? Our subjects listened to spoken stories. Then, to measure their comprehension, they answered multiple-choice questions about each story. During some stories, they were required to detect a specific phoneme; during other stories, they were required to detect a specific word; during still other stories, they were not required to monitor the utterance for any target. The monitoring results replicated earlier findings showing longer detection latencies for phoneme monitoring than for word monitoring. Somewhat surprisingly, the ancillary phoneme- and word-monitoring tasks did not adversely affect overall comprehension performance. This result undermines the specific criticism that on-line monitoring paradigms of this kind should not be used to study spoken language understanding because these tasks interfere with normal comprehension.  相似文献   
992.
Pennsylvania State University, University Park, Pennsylvania 16802 The influence of refractive error on movement sensitivity was determined for a range of stimulus durations in the fovea and periphery. At short durations, threshold is determined by a constant displacement of the stimulus. At longer durations, a constant velocity is required. The correction of peripheral refractive error increases movement sensitivity in the displacement (short duration) component, but does not influence sensitivity in the velocity (long duration) component of the motion threshold. Implications concerning the mechanisms underlying motion perception are discussed.  相似文献   
993.
Human contrast sensitivity is known to vary with both stimulus spatial frequency and orientation. Previous research has indicated, however, that the apparent contrast of a sinusoidal grating is independent of spatial frequency at suprathreshold levels. We have found that the apparent contrast of suprathreshold gratings is not independent of its orientation. Observers adjusted the apparent contrasts of vertical and oblique gratings to match a 40% standard. Contrast match deviations were found at a number of spatial frequencies, indicating a lack of contrast constancy with stimulus orientation. The apparent contrast of gratings in different orientations could not be predicted in any simple fashion from either contrast threshold differences or ratios.  相似文献   
994.
Validation of the Differential Emotions Scale in 613 mothers   总被引:1,自引:0,他引:1  
Mothers (N=613) with infants who took the Differential Emotions Scale (DES) were compared in a cross-validation study by factor analysis to 957 high school and college students. Despite differences in factor-analytic technique, similarities in factor structure suggested that the DES discriminates the majority of fundamental emotions as posited by Izard.Robert Emde is supported by Research Scientists Award No. 5 KO5 MH 36808 and NIMH Project Grant No. 2 RO1 MH 22803. The authors wish to acknowledge the critical support of the Developmental Psychobiology Research Group, Department of Psychiatry, University of Colorado Medical School, and wish to express their gratitude to Carroll Izard for allowing us to publish his factor-analytic results.  相似文献   
995.
Previous work has shown that adults and older children tend to classify multi-dimensional objects by identity on one dimension, whereas children under 8 years of age tend to classify these same objects by a relation of overall similarity. The present study investigated the hypothesis that this developmental trend is restricted to the classification of simple objects that differ only by limited amounts on a few dimensions. The specific hypothesis was that overall-similarity relations structure both adults' and children's classifications of heterogenous objects (objects that differ in a variety of ways). This hypothesis was suggested by the correspondence between the structure of young children's classifications and the structure of natural categories. The result of two experiments supported the hypothesis. When the to-be-classified objects varied simultaneously on relatively many dimensions, adults as well as children constructed classifications that maximized within-category similarity on all varying dimensions. The implications of these results for accounts of the perception of multidimensional relations and classificatory behavior are discussed.  相似文献   
996.
The effects of valence of alternatives, choice, and expected delay of choice consequences on postdecision evaluations of choice alternatives were studied by either giving subjects a choice between two experimental tasks (both either pleasant or unpleasant) or assigning subjects their initially preferred task. Crosscutting valence and choice, subjects expected either no delay, 10-min delay, or 30-min delay before engaging in the task. All subjects evaluated both tasks immediately after the delay instructions but before experiencing the actual delay. Results confirmed the expected dissonance effect; that is, an upward evaluation of the chosen alternative and a downward evaluation of the rejected alternative, relative to no-choice conditions. Moreover, the relative upward evaluation of the chosen alternative increased as the expected delay decreased. Valence was not found to interact with other variables. The results are discussed in terms of differential salience of choice alternatives.  相似文献   
997.
The present study examined differences in pelvic vasocongestion as a function of negative attitudes toward masturbation. Pelvic vasocongestion was measured thermographically, which is a noninvasive means of detecting and photographing individual heat patterns to indicate physiological condition and functional changes within. The results indicated that women, with positive attitudes toward masturbation, who read an erotic story, experienced the greatest increase in pelvic vasocongestion. This and other findings were discussed in terms of masturbation acting to facilitate the patterning of sexual arousal and orgasmic functioning, especially in regard to creating the capacity for pelvic engorgement.  相似文献   
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