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991.
992.
H G Smid W Lamain M M Hogeboom G Mulder L J Mulder 《Journal of experimental psychology. Human perception and performance》1991,17(3):696-714
This study was designed to test whether information transmission between the perceptual and motor levels occurs continuously or in discrete steps. Ss performed visual search across nontargets that shared visual features with one of two possible targets, each assigned to a different response. In addition to reaction time, psychophysiological measures were used to assess the duration of target search and the onset of central and peripheral motor activity. Nontargets sharing features with a target selectively activated the response associated with that target, even when it was not present in the display. This suggests that information transmission to the motor level can consist of fine-grained visual information and that visual search and response selection occur in parallel. 相似文献
993.
This study investigated longitudinal relations between measures of neonatal state behavior and developmental outcome in a sample of preterm infants (N = 16). Results indicate that irritability/reactivity in the neonatal period is positively associated with Bayley scores and exploratory play at 8 months. Conversely, neonatal alertness was not associated with these developmental measures. These preliminary findings, based on a small sample, are discussed in the context of preterm function. 相似文献
994.
The detectability of a target pattern presented briefly with a number of similar nontarget patterns varies as a function of the spatial location of the target. Previous work attributes these detectability gradients to a visual search process--a non-eye movement serial scan--that examines a decaying neural representation of the image. (Heron, 1957; Efron, Yund, & Nichols, 1987, 1990a,b,c; Yund, Efron, & Nichols, 1990a,b,c). The results reported in the companion paper (Ostrosky-Solis, Efron, & Yund, 1991) indicated that literacy did not affect overall performance levels but did influence scanning behavior: "...reading, or learning to read, caused the scanning mechanisms of literate subjects to adopt more consistent scan paths, from subject to subject, than they would have adopted without this reading experience." The purpose of the present experiment was to determine the effect on this scanning mechanism, if any, of an entirely different type of visual experience--the high-speed visual processing required of tennis players. Unlike reading which requires the linguistic interpretation of a highly structured visual input, tennis skill requires rapid target detection and tracking in three-dimensional visual space as well as large scale visual-motor coordination. As in the previous experiments, subjects were required to detect a vertical stripe pattern among a number of similar non-target patterns. The experiment was performed on a group of 52 tennis players and on an age- and sex-matched group of 52 non-tennis players. The overall accuracy of target detection was greater among the tennis players than among the non-tennis players and, of more interest, there was a significant difference in the detectability gradients. The detection advantage of the tennis group seemed to reach its maximum in the first half of the scan and then to deteriorate as the scan proceeded. These results indicate that visual experience other than reading can affect the habitual activity of the scanning mechanism. 相似文献
995.
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
996.
Self-management of diabetes mellitus: a critical review 总被引:5,自引:0,他引:5
Diabetes has no known cure and is a leading source of morbidity and mortality. Clinical management involves patients managing a complex and variable regimen. This article reviews the determinants of effective self-management and the methods of promoting better self-management. Trait variables (e.g., personality and demographics) have been presumed to affect self-management, but evidence suggests they have little impact. The important determinants of self-management are transient situational factors such as psychological stress and social pressure to eat. Interventions to promote better self-management have reported initial improvements in blood glucose control, but the long-term effects are unclear. We conclude that self-management has been inadequately assessed and that attempts to improve self-management have relied excessively on providing information. More research is needed to clarify determinants of self-management, and interventions to improve self-management will need to change these determinants. 相似文献
997.
Phyllis Kernoff Mansfield Patricia Barthalow Koch Julie Henderson Judith R. Vicary Margaret Cohn Elaine W. Young 《Sex roles》1991,25(1-2):63-79
Rapid growth has been observed in recent years in the number of women entering traditionally male blue-collar occupations, yet researchers have paid little attention to this pioneering group. The present study undertook a comparison of the job conditions of two groups of nontraditional women workers, tradeswomen (N=71), and transit workers (N=151); a third group, school secretaries (N=389), was studied as a comparison group of traditionally female workers. Results from a 16-page mail questionnaire revealed that women in traditionally male occupations encountered significantly more adverse working conditions than did their traditional counterparts, and, in addition, reported significantly less satisfaction and more stress at work. Tradeswomen were the most likely to experience sexual harassment and sex discrimination, and black tradeswomen to experience race discrimination. The degree of job satisfaction expressed by the secretaries was unexpected, since most evidence suggests that clerical workers lack autonomy, and encounter boredom and routinization on the job. These findings are discussed in terms of gender segregation and the need to focus future research efforts on specific occupational groups in order to make appropriate policy recommendations as well as to provide help for women in these jobs.This research was supported by grants from the National Institute for Occupational Safety and Health (Grant No. 1 RO1 OH02162-01A1) and the College of Health and Human Development, The Pennsylvania State University. The authors wish to acknowledge the invaluable contributions of Patty Lambert, Ming Qi Wang, Mary Harmon, Joseph Vasey, Gina Jay, Darrell Harvey, and Haleh Rastegary. 相似文献
998.
Dr. Paul Kymissis M.D. William L. Licamele M.D. Sandra Boots M.S.W.L.C.S.W. Edwin Kessler M.D. 《Group》1991,15(3):163-167
Although group therapy is widely used in the treatment of children and adolescents, there has been little attention paid to establishing training standards and developing comprehensive programs for training psychiatry fellows in child and adolescent group psychotherapy. The authors conducted two surveys of child and adolescent training programs. After reviewing the literature, they present the data from their surveys, compare similarities and differences, and discuss trends. Finally, they propose a model for training in child and adolescent group therapy. 相似文献
999.
W J Zielinski J G Vandenbergh 《Journal of comparative psychology (Washington, D.C. : 1983)》1991,105(2):134-139
In laboratory strains of mice, reproductive maturation is influenced by both the fetal and the peripubertal social environments experienced by females. Intrauterine position (IUP) for female fetuses is identified by the number of adjacent males; where 0M have zero, 1M have one, and 2M have two male neighbors. We sought to confirm, using wild-type female house mice (Mus musculus), the previous finding in the CF-1 strain of laboratory mouse that males prefer 0M over 2M females as mates. We recorded the age at first reproduction for females of known IUP housed either individually with a male or in a group of 6 females and a male. In neither housing condition were there significant differences in age of first reproduction among females of different IUPs, but 0M females that were group housed had perforate vaginas at an earlier age than other group-housed females. Mean (+/- SE) age at first reproduction was 58.1 (+/- 3.3) for paired and 126.6 (+/- 5.1) for group-housed females. The reproductive suppression observed in the grouped females was probably due to the interaction of inhibitory urinary chemosignals, low body weights, and female dominance hierarchies. 相似文献
1000.
Steve W. J. Kozlowski J. Kevin Ford 《Organizational behavior and human decision processes》1991,49(2)
Research on performance ratings has tended to neglect factors affecting raters' acquisition of ratee performance information. The present research examined the dynamic effects of this rater information acquisition process. Study 1 examined the effects of prior ratee knowledge (familiarity) and ratee performance level on subsequent acquisition of ratee performance information under varying levels of constraint. After exposure to prior ratee information, raters acquired additional information concerning a set of ratees using a computer controlled information board procedure. The results indicated significant effects on the amount of search for prior knowledge, search constraint, and the interaction between prior knowledge and performance level. Study 2 extended the research by including a memory component (time delay) between the exposure to prior information and subsequent search. Results were congruent with Study 1. They indicated significant main effects on the amount of search for prior knowledge, ratee performance level, search constraint, and on the interaction between prior knowledge and performance level. In addition, the results indicated a significant interaction between memory demand and prior knowledge. Implications of these results, limitations, and extensions of this research approach are discussed. 相似文献