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181.
Enhanced right hemisphere activation in the mathematically precocious: A preliminary EEG investigation 总被引:3,自引:0,他引:3
Michael W. O''boyle Joel E. Alexander Camilla Persson Benbow 《Brain and cognition》1991,17(2):138-153
A preliminary electroencephalographic (EEG) investigation was conducted to determine if the pattern of hemispheric activation in mathematically precocious youth differs from that of average math ability subjects. Alpha activity at four brain sites (frontal, temporal, parietal, and occipital lobes) over the left and right cerebral hemispheres (LH/RH) was monitored while 12- to 14-year-old, right-handed males: (a) looked at a blank slide (baseline condition), (b) judged which of two chimeric faces was "happier," and (c) determined if a word was a noun or a verb. At baseline, the LH of the precocious group was found to be more active at all four brain sites relative to that of the average ability group. During chimeric face processing, the gifted subjects exhibited a significant reduction in alpha power over the RH, primarily at the temporal lobe, while no such alpha suppression was observed in the average ability subjects. For noun/verb determinations, no significant alpha power reductions were obtained for either group. These electrophysiological data generally corroborate the behavioral findings of O'Boyle and Benbow (1990a) and support their contention that enhanced RH involvement during cognitive processing may be a correlate of mathematical precocity. Moreover, the pattern of activation observed across tasks suggests that the ability to effectively coordinate LH and RH processing resources at an early age may be linked to intellectual giftedness. 相似文献
182.
Attractiveness ratings of 50 children aged 12–38 months were investigated in relation to adult socializing agents' behavior toward the children in their homes and play groups and their attitudes toward the children. Attractiveness scores were derived from 43 judges' ratings of facial photographs of the children. The same children were observed in play groups with female care givers; 40 of them were also observed in their homes with their parents. Play-group care givers rated the children for likability, tractability, and peer relations. Parents rated their attitudes toward giving routine care to their child. Attractiveness scores were not correlated with any adult attitude measures. Girls' attractiveness scores were positively correlated with their attempts to communicate in home and play group, and with mothers', fathers', and care givers' instructional responses, but negatively correlated with passive behavior in the home and with mothers' positive reactions. Boys' attractiveness scores were negatively correlated with passive behavior in the play group; no other significant correlations were found in the data for boys. 相似文献
183.
This study examined the relationships among five measures that assess various cognitive components of the child's acquisition of gender. At around 2 years of age, children were given a task assessing their ability to accurately label as a boy or a girl some head-and-shoulders pictures of boys and girls. At 4 years of age, these children were given tasks measuring (1) the degree to which they found gender a salient parameter of categorization, (2) the amount of gender-related knowledge they could display (SERLI-SRD), (3) the degree to which their preferences were gender-typed (SERLI-SRP) and (4) the accuracy of their memory for gender-typed information. There was no consistent pattern of relationship among the children's scores on these five tools for measuring gender acquisition. Our findings suggest that gender is a multidimensional construct in children's development, and thus these results challenge the undimensional manner in which gender is repeatedly addressed in developmental theory and research.This research was funded in part by a federal biomedical research grant (No. 2507RR07080) awarded to the first author from the Department of Psychology at the University of Oregon, and by Grant No. RO1HD175751 from the National Institute of Child Development awarded to the third author.We wish to thank Margo Lane, Rachel Robertson, Jacqui Oucalt, Laura Baker, Dale Roberts, and the teachers, parents, and assistants of the Child Research Laboratory at the University of Oregon in Eugene, Oregon, for their invaluable contribution to this research. 相似文献
184.
The purpose of this study was to investigate the effect of cosmetics use on attributions concerning the likelihood of provoking sexual harassment and of being sexually harassed. Subjects were 85 female and 76 male undergraduate volunteers. The study was a 3×2 between-subjects design with three levels of cosmetics use (heavy, moderate, no cosmetics) and two levels of sex of subject (male, female). Each subject viewed one of three colored photographs of a model wearing either heavy, moderate, or no cosmetics, and then indicated how likely the model was to provoke sexual harassment and to be sexually harassed. Data were analyzed using analyses of variance and the Newman-Keuls test. When the model wore heavy cosmetics, she was rated as more likely to provoke sexual harassment than when she wore moderate cosmetics. Similarly, when the model wore moderate cosmetics, she was rated as significantly more likely to provoke sexual harassment than when she was not wearing cosmetics. When the model wore either heavy or moderate cosmetics, she was also rated as more likely to be sexually harassed than when she did not wear cosmetics. In addition, male subjects rated the model as more likely to provoke and to be sexually harassed than did female subjects. Results are discussed in terms of sex role spillover. 相似文献
185.
186.
Robert D. Sorkin Thomas R. Mabry Mary Susan Weldon Greg Elvers 《Organizational behavior and human decision processes》1991,49(2)
This experiment examined the processing of information from multiple element visual displays, using techniques derived from the theory of signal detectability. The method allows one to specify how observers integrate information from individual elements of a display. The experiment tested numerical and graphical displays having different display sizes, durations, and arrangements of elements. Observer performance increased with the number, m, of display elements, but at less than the ideal √m rate. Observer performance was consistent with a model of information integration constrained by internal noise. Linear arrays of elements resulted in better performance than did square arrays. Graphically coded elements resulted in better performance than did numerical elements. Observer decision weighting of element information from graphical displays was approximately uniform across spatial position, but the weighting of information from numerical displays was concentrated on elements near the fixation point. 相似文献
187.
When was the last time you saw a job application with no spelling or grammatical errors? Basic skill deficiencies among people at all levels of business are forcing companies to develop innovative ways of compensating for and correcting the problem. What follows is a summary of literacy training strategies and suggestions for implementation. 相似文献
188.
Analysis of the elements of attention: A neuropsychological approach 总被引:15,自引:0,他引:15
Allan F. Mirsky Bruno J. Anthony Connie C. Duncan Mary Beth Ahearn Sheppard G. Kellam 《Neuropsychology review》1991,2(2):109-145
A model for conceptualizing the components or elements of attention is presented. The model substitutes for the diffuse and global concept of attention a group of four processes and links them to a putative system of cerebral structures. Data in support of the model are presented; they are derived from neuropsychological test scores obtained from two samples, the first consisting of 203 adult neuropsychiatric patients and normal control subjects, and the second, an epidemiologically-based sample of 435 elementary school children. Principal components analyses of test scores from these two populations yielded similar results: a set of independent elements of attention that are assayed by different tests. This work presents a heuristic for clinical research in which the measurement of attention is essential. 相似文献
189.
This paper considers some mathematical aspects of minimum trace factor analysis (MTFA). The uniqueness of an optimal point of MTFA is proved and necessary and sufficient conditions for a point x to be optimal are established. Finally, some results about the connection between MTFA and the classical minimum rank factor analysis will be presented. 相似文献
190.