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921.
Observers classified sine-wave and square-wave gratings on the basis of fundamental frequency (Are the bars wide or narrow?) or on the basis of higher harmonic frequencies (Are the bars sharp or fuzzy?). Stimuli were presented in either the left (LVF) or right (RVF) visual field. When the classification was made on the basis of the fundamental frequencies (1 or 3 c/deg), there was a LVF/right hemisphere advantage. However, when the classification was on the basis of a sharp/fuzzy distinction which involved searching for the higher harmonic frequencies, then a RVF/left hemisphere advantage was found. 相似文献
922.
The purpose of the present study was to determine if there were differences in hemispheric lateralization during the experience of emotions and if those differences were related to personality style. College-age adult subjects selected for high positive and negative affectivity on Tellegen's Multidimensional Personality Questionnaire (MPQ; Tellegen, 1982) viewed video stimuli selected for their emotionally evocative nature and rated the intensity of the emotions they experienced. The ongoing electroencephalogram (EEG) was recorded while they watched the video clips. Analyses of the EEG data revealed that there were differences in regional activation during the emotional video clips, especially for those stimuli selected to elicit either happy or disgust emotions. These results support the hypothesis that the right hemisphere is specialized for the experience of certain negative affects, whereas the left hemisphere is specialized for the experience of certain positive affects. The findings also indicated some support for the theory that individual differences in personality style are related to differing levels of hemispheric arousal. 相似文献
923.
Laird S. Cermak Mieke Verfaellie Marie Sweeney Larry L. Jacoby 《Brain and cognition》1992,20(2):367-377
To examine the relative contribution of fluency and recollection to the word completion performance of amnesics, we administered a task in which patients were told specifically not to utilize previously presented words during stem completion (an Exclusion condition). This condition was contrasted with a standard word completion task in which patients were encouraged simply to complete the stem with the first word that came to mind (an Inclusion condition). Since the exclusion condition necessitated controlled respecification of the initial presentation, it was hypothesized that amnesics would be less able than controls to exclude study list items. Consistent with this hypothesis, the results indicated that the amnesics' performance, unlike that of the alcoholic controls, did not significantly differ as a function of task condition. To examine whether amnesics' conscious recollection could be enhanced, Experiment 2 presented the study list five times. The amnesics now were able to exclude a significant number of items from the study list; however, they still did so considerably less frequently than alcoholic controls. For the alcoholic controls, increasing the number of study trials had little additional effect on their exclusion performance, but it significantly enhanced their inclusion performance. Taken together, these findings suggest that for control subjects, word completion performance is likely mediated by a combination of fluency and recollection, while for amnesic patients, performance is almost exclusively based on the fluency with which an item comes to mind. 相似文献
924.
In a group of male and female subjects we studied the VEPs related to the solution of a lexical decision task presented in the Left and Right Hemispaces with respect to the Central position in order to explore the electrophysiological correlates of the performance asymmetries obtained when overt spatial attention is directed to the Left or Right Hemispace. When stimuli were presented in the Left Hemispace a significant asymmetry was observed between the two hemispheres of the negative activity around 280 msec in the occipital-parietal areas. Moreover a general increase in the Central and Frontal areas of both the hemispheres was observed. In this paper we discuss why these effects can be considered to be the cause of the costs on accuracy observed in the male subjects. The differences obtained with the female group are discussed in relation to the observed modification on the negative activity around 400 msec with stimuli in the Left Hemispace. These findings give some suggestions about the interaction of structural and attentional mechanisms in the brain during the solution of a lateralized cognitive task. 相似文献
925.
926.
927.
On the Relation Between Time Perception and the Timing of Motor Action: Evidence for a Temporal Oscillator Controlling the Timing of Movement 总被引:7,自引:0,他引:7
Michel Treisman Andrew Faulkner Peter L. N. Naish 《The Quarterly Journal of Experimental Psychology Section A: Human Experimental Psychology》1992,45(2):235-263
Studies of time estimation have provided evidence that human time perception is determined by an internal clock containing a temporal oscillator and have also provided estimates of the frequency of this oscillator (Treisman, Faulkner, Naish, & Brogan, 1992; Treisman & Brogan, 1992). These estimates were based on the observation that when the intervals to be estimated are accompanied by auditory clicks that recur at certain critical rates, perturbations in time estimation occur. To test the hypothesis that the mechanisms that underlie the perception of time and those that control the timing of motor performance are similar, analogous experiments were performed on motor timing, with the object of seeing whether evidence for a clock would be obtained and if so whether its properties resemble those of the time perception clock. The prediction was made that perturbations in motor timing would be seen at the same or similar critical auditory click rates. The experiments examined choice reaction time and typing. The results support the hypothesis that a temporal oscillator paces motor performance and that this oscillator is similar to the oscillator underlying time perception. They also provide an estimate of the characteristic frequency of the oscillator. 相似文献
928.
This article describes a study conducted to identify the range of potential influences that a computer-assisted careers guidance system (PROSPECT (HE)) had on the functioning of organisations (careers services in higher education). Data from six institutions indicated that use of PROSPECT (HE) was associated with important and varied change within the organisations. It appears that when a careers service seeks opportunities for change, CACG systems can be an important catalyst for change in two respects: by providing a focal point for achieving previously established goals; or, as a consequence of system use, by making staff aware of the potential for new organisational goals. 相似文献
929.
Gender differences in children's play activities, preferred school subjects, and occupational goals were examined in relation to such parental variables as toy-giving and chore assignment. Subjects were 245 children in grades K, 3, 6, and 8. Subjects completed questionnaires before and after Christmas asking what gifts they wanted, asked for, received, and liked best. They also were asked to name their friends and play activities, favorite and least-liked school subjects, occupational aspirations, and chores at home. Children generally wanted, asked for, received, and most-liked gender-typical toys. They were less likely to receive requested gender-atypical toys. Children's preferred activities, job aspirations and assigned chores were along gender-typical lines. Girls preferred masculine toys and jobs more than boys preferred feminine ones. With increasing age, both girls and boys increasingly preferred masculine toys and male friends. No gender differences in favorite or least-liked school subjects were found. School subject preference was related to gender-typing of occupational choice for girls but not boys.An earlier version of this paper was presented at the annual meeting of the American Psychological Association, Anaheim, California, 1983. 相似文献
930.
A 3×2×2 incomplete factorial design was employed to test the effects of sex, dominance, and their interaction on leader emergence. The factors included dominance distribution (high/high, high/low, middle/middle), sex (male-female), and dyad composition (mixed sex-same sex). The subjects were all Caucasians and were pretested on the California Psychological Inventory Dominance Scale. The data revealed that dominance was a predictor of leader emergence in same-sex conditions where high-dominant individuals assumed the role of leader in much greater proportions than their low-dominant partners. In mixed-sex dyads, sex appeared to be a more potent predictor with males becoming leaders at levels greater than would be suspected given dominance levels. 相似文献