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991.
The perceived spatial frequency of a visual pattern can increase when a pattern drifts or is presented at a peripheral visual field location, as compared with a foveally viewed, stationary pattern. We confirmed previously reported effects of motion on foveally viewed patterns and of location on stationary patterns and extended this analysis to the effect of motion on peripherally viewed patterns and the effect of location on drifting patterns. Most central to our investigation was the combined effect of temporal modulation and spatial location on perceived spatial frequency. The group data, as well as the individual sets of data for most observers, are consistent with the mathematical concept of separability for the effects of temporal modulation and spatial location on perceived spatial frequency. Two qualitative psychophysical models suggest explanations for the effects. Both models assume that the receptive-field sizes of a set of underlying psychophysical mechanisms monotonically change as a function of temporal modulation or visual field location, whereas the perceptual labels attached to a set of channels remain invariant. These models predict that drifting or peripheral viewing of a pattern will cause a shift in the perceived spatial frequency of the pattern to a higher apparent spatial frequency.  相似文献   
992.
The cyclic variation in the energy envelope of the speech signal results from the production of speech in syllables. This acoustic property is often identified as a source of information in the perception of syllable attributes, though spectral variation can also provide this information reliably. In the present study of the relative contributions of the energy and spectral envelopes in speech perception, we employed sinusoidal replicas of utterances, which permitted us to examine the roles of these acoustic properties in establishing or maintaining time-varying perceptual coherence. Three experiments were carried out to assess the independent perceptual effects of variation in sinusoidal amplitude and frequency, using sentence-length signals. In Experiment 1, we found that the fine grain of amplitude variation was not necessary for the perception of segmental and suprasegmental linguistic attributes; in Experiment 2, we found that amplitude was nonetheless effective in influencing syllable perception, and that in some circumstances it was crucial to segmental perception; in Experiment 3, we observed that coarse-grain amplitude variation, above all, proved to be extremely important in phonetic perception. We conclude that in perceiving sinusoidal replicas, the perceiver derives much from following the coherent pattern of frequency variation and gross signal energy, but probably derives rather little from tracking the precise details of the energy envelope. These findings encourage the view that the perceiver uses time-varying acoustic properties selectively in understanding speech.  相似文献   
993.
The Test of Nonverbal Intelligence (TONI) and Wechsler Intelligence Scale for Children--Revised (WISC--R) were administered to 46 Native American and white students who were suspected by their classroom teachers of having learning handicaps. Pearson correlations between these sets of IQs ranged from .42 (TONI and WISC--R Performance) to .89 (WISC--R Verbal and Full Scale).  相似文献   
994.
Two studies examined the speed with which good spellers and poor spellers spell easy and difficult words. At both the elementary school (Grades 3 and 4) and undergraduate levels, good spellers spelled words more quickly than poor spellers. This difference appeared even for very easy words that all subjects could spell. Implications for the importance of automaticity in spelling competence are discussed.  相似文献   
995.
Conclusion Given my dilemma, then, we should think twice before following Putnam away from metaphysical realism. Internal realism can offer only a false sense of philosophical security. And now we may doubt that it can offer even that.  相似文献   
996.
E L?chel 《Psyche》1990,44(9):826-847
The author presents different psychoanalytic conceptualizations of gender difference. She reviews the controversy between Freud and Jones and discusses in detail the views put forward by Montrelay, a student of Lacan, who relates early linguistic development to gender-specific differences in closeness between the child and the "mother's body".  相似文献   
997.
The power of moral ideas, here equated with superego strength, has been explained in increasingly complex terms over the course of the development of psychoanalysis. At first regarded mainly as useful in opposing oedipal instinctual demands, morality came to be seen also as opposed to aggressive wishes while at the same time capable of gratifying aggressive and libidinal forces. In this paper, I discuss the contribution to the strength of morality that comes from the effects of painful ("traumatic") experiences and from the use of moral ideas for social, adaptational purposes. In addition I consider the possibility that unchanging moral ideas can have changes in function in clinical work. A case is presented to illustrate these points.  相似文献   
998.
999.
Residents of a county nursing home underwent a forced, mass relocation. Gerontologists advised on preparation of staff and residents. No increase in residents' mortality or morbidity was found after the relocation. The highest death rate was in the anticipatory period, the year prior to the move.  相似文献   
1000.
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