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Temporal contrast sensitivity for counterphase flicker was determined for specifically disabled and normal readers to investigate whether the two groups differ in the functioning of their transient systems. In experiment 1, temporal contrast sensitivity was measured over a range of temporal frequencies with a spatial frequency of 2 cycles deg-1. Disabled readers were less sensitive than the control subjects at all temporal frequencies. In experiment 2, temporal contrast sensitivity was measured at a temporal frequency of 20 Hz over a range of spatial frequencies. Disabled readers were less sensitive than the controls at all spatial frequencies, with the differences between the groups increasing as spatial frequency increased. Both these findings are interpreted as supporting the hypothesis of a transient-system deficit in the visual systems of disabled readers. 相似文献
887.
The marriage role expectations of female university students enrolled in an introductory marriage and family course at the University of Kentucky in 1961 (N=72), 1972 (N=58), 1978 (N=115), and 1984 (N=81) were compared. The 1972 group was found to be significantly more egalitarian than the 1961 group in overall marriage role expectations and on all subscales except authority. The 1978 and 1984 groups were significantly more egalitarian than the 1961 group on overall marriage role expectations and on all seven of the subscales: authority, homemaking, child care, personal characteristics, social participation, education, and employment and support. The 1978 group was significantly more egalitarian than the 1972 group only on authority and homemaking, with no significant differences on the other five subscales or on overall role expectation score. The 1984 group was significantly more egalitarian than the 1972 group only on authority, homemaking, and child care, and was slightly (not satistically significant) more traditional on personal characteristics and social participation. There were no significant differences between the 1978 and 1984 groups on overall expectation or on any of the subscales. In fact, the 1984 group was slightly more traditional on homemaking, personal characteristics, social participation, employment and support, and overall expectations. The data from this study showed the greatest gain in egalitarian trends to be between 1961 and 1972, with a continuation of the trends at a somewhat slower rate of change between 1972 and 1978, and a discontinuation of the trend toward more egalitarian expectations between 1978 and 1984.The data were collected in February 1961, January 1972, September 1978, and September 1984. Special acknowledgement and appreciation are expressed to Jessie Ringo (retired), University of Kentucky, for making the 1961 data available for this study. 相似文献
888.
Relative effectiveness of three stimulus variables for locating a moving sound source 总被引:1,自引:0,他引:1
A study is reported in which it is shown that observers can use at least three types of acoustic variables that indicate reliably when a moving sound source is passing: interaural temporal differences, the Doppler effect, and amplitude change. Each of these variables was presented in isolation and each was successful in indicating when a (stimulated) moving sound source passed an observer. These three variables were put into competition (with each indicating that closest passage occurred at a different time) in an effort to determine their relative importance. It was found that amplitude change dominated interaural temporal differences which, in turn, dominated the Doppler effect stimulus variable. The results are discussed in terms of two interpretations. First, it is possible that subjects based their judgements on the potential discriminability of each stimulus variable. However, because the stimuli used involved easily discriminable changes, subjects may instead have based their judgements on the independence of a stimulus variable from different environmental situation conditions. The dominance ordering obtained supports the second interpretation. 相似文献
889.
Brain potentials as indices of orthographic and phonological interaction during word matching 总被引:4,自引:0,他引:4
A F Kramer E Donchin 《Journal of experimental psychology. Learning, memory, and cognition》1987,13(1):76-86
The interaction between orthographic and phonological codes in a same-different judgment task was studied by requiring subjects to decide if two visually presented words either looked alike or rhymed. Word pairs were selected from four different lists. Words rhymed and looked alike, rhymed but did not look alike, looked alike but did not rhyme, or neither looked alike nor rhymed. Reaction time and percent error increased whenever there was a conflict between the orthography and phonology of the words. The N200 component of the event-related brain potential (ERP) indicated that subjects were capable of detecting phonological differences between words within 260 ms from the presentation of a word pair. The amplitude of the N200s also varied with the degree of mismatch between words. N200s were largest when both the orthography and phonology mismatched, of intermediate amplitude when either orthography or phonology mismatched, and smallest when both orthography and phonology matched. P300 latency was consistent with reaction time, increasing whenever there was a conflict between the two codes. Taken together, behavioral measures and the ERP data suggest that the extraction of the orthographic and phonological aspects of words occurs early in the information processing sequence. 相似文献
890.
J C Bartlett M A Gernsbacher R E Till 《Journal of experimental psychology. Learning, memory, and cognition》1987,13(1):27-35
In a study of recognition memory for pictures, we observed an asymmetry in classifying test items as "same" versus "different" in left-right orientation: Identical copies of previously viewed items were classified more accurately than left-right reversals of those items. Response bias could not explain this asymmetry, and, moreover, correct "same" and "different" classifications were independently manipulable: Whereas repetition of input pictures (one vs. two presentations) affected primarily correct "same" classifications, retention interval (3 hr vs. 1 week) affected primarily correct "different" classifications. In addition, repetition but not retention interval affected judgments that previously seen pictures (both identical and reversed) were "old". These and additional findings supported a dual-process hypothesis that links "same" classifications to high familiarity, and "different" classifications to conscious sampling of images of previously viewed pictures. 相似文献