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81.
Flicker contrast sensitivity in normal and specifically disabled readers   总被引:4,自引:0,他引:4  
F Martin  W Lovegrove 《Perception》1987,16(2):215-221
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   
82.
Two hundred and sixty three young adult college students responded to openended questions assessing their specific intentions, motives, and plans for having children. The most commonly stated motives for childbearing reflected a strong interest in establishing an identity and social network. Financial, marital, and emotional stability were identified as important factors influencing the timing of parenthood. Several significant sex differences were found for both motives and the timing of parenthood. These findings are discussed in terms of changing social norms regarding parenthood and changing sex role expectations.Portions of this research were presented at the Eastern Regional Psychological Association Convention in New York, April 1986. This research was funded by a grant from Trenton State College, Committee for Faculty and Institutional Research and Sabbatical Leave.  相似文献   
83.
A major home improvement chain located primarily in the western United States initiated the use of thePersonnel Selection Inventory, a written integrity test, as part of its pre-employment hiring process. For two years only, those job applicants who passed this test and other pre-employment criteria were hired by the chain. Following the introduction of the inventory, there was: (1) a 50% reduction in the number of employee terminations for theft, illegal drug use, and violence over a five year period and (2) a savings in shrinkage losses that amounted to over two million dollars over a two year period.  相似文献   
84.
Baron and Ransberger (1978) argue that civil violence increases as temperature rises into the mid 80s, and then decreases as temperatures rise further. Two experiments test this hypothesis using data on temperature and the incidence of crime for summer months in two midwestern cities. The crime data were divided into violent and nonviolent crimes, and then correlated with the maximum, minimum, and average temperatures, and several humidity measures. Violent crime correlated significantly with temperature; nonviolent crime did not. This relationship was linear in the first study, but curvilinear in the second. Inspection of the data suggests that the incidence of aggressive behavior (i.e., violent crime) does not drop off in the mid-80s as laboratory findings and Baron and Ransberger's results would suggest, but continues to increase as temperatures rise into the 90s. The mean incidence of violent crime was higher for days in the 90s than for days in the 80s. A hypothesis for resolving this contradiction between real world and laboratory findings is discussed.  相似文献   
85.
86.
Predicting adult temperament from minor physical anomalies   总被引:1,自引:0,他引:1  
It is known that in children, individual differences in temperament are linked to rates of minor physical anomalies (MPAs). These anomalies are a standard set of 17 nonobvious but measurable characteristics of the face, hands, and feet. We explored the relation between MPAs and temperament in adults. An intact sample of 88 undergraduates completed a battery of personality tests and lifestyle questions, and then were examined for MPAs. The index of MPAs for each subject was simply the total count out of 17. The results showed a pattern of correlates parallel to that found in children. Among male subjects, correlations with MPAs were significant for the Physical Activity and Clumsiness factors of the lifestyle inventory as well as for measures of emotionality, extraversion, masculinity, femininity, and Type A personality. The MPA index was also predictive of a behavioral index of temperament in male subjects. No correlations were significant among female subjects.  相似文献   
87.
John F. Halpin 《Synthese》1986,69(3):325-340
In his (1981) paper, Stalnaker has revised his old theory of conditionals and has given the revision an interesting defense. Indeed, Stalnaker shows that this new theory meets the standard objections put to the old. However, I argue that the revision runs into difficulties in the context of quantum mechanics: If Stalnaker's theory of the conditional is assumed, then from plausible assumptions certain Bell-like conflicts with experiment can be derived. This result, I go on to argue, is a good reason to reject Stalnaker's theory, at least for the quantum mechanical context.I wish to thank Arthur Fine, Paul Teller, Dorothy Grover, and Anil Gupta for their helpful comments and criticisms on earlier drafts of this paper.  相似文献   
88.
Recent research suggests that anxiety is not a single, unified reaction to perceived threat, but rather a cluster of interrelated factors whose relationships to performance change as the individual progresses from one test event to another. This study investigated the presumed linkages between traitlike predispositions to perceive threat and achievement performance, as mediated by statelike anxiety arousal on a longitudinal basis (Perceived Threat Anxiety Arousal Impaired Performance). College students were administered self-report questionnaire measures during a preenrollment period, after the first two midterms, and following the last two midterms in a general psychology course. Four performance measures and 26 motivational indicators were fitted to a 10-factor latent model using LISREL model-fitting techniques. Path-analytic interpretations of this structural model provided little evidence for the commonly held view that traitlike threat perceptions mediate performance via statelike anxiety reactions. Far more promising, theoretically, are those influences on test performance stemming from the self-attributional, cognitive domain. Overall, the findings support a recent reinterpretation of achievement anxiety as stemming from the disruptive effects of diminished ability perceptions (and hence, impaired personal worth), rather than from the interfering influence of diffused emotional arousalper se.  相似文献   
89.
Despite speculation that sucrose consumption affects behavior, little empirical information is available. Accordingly, this study investigated the effect of sucrose consumption on the behavior of eight preschool children. Children were tested individually using a double-blind, crossover design. On separate mornings each child received 6 ounces of juice, sweetened on one morning with sucrose and on the other with an artificial sweetener. Children were observed for 90 minutes following the drinks, alternating between 15-minute sessions of work on structured tasks and 15-minute sessions of free play. Following the sucrose drink the children showed a decrement in performance in the structured testing situation, and they demonstrated more inappropriate behavior during free play. These differences in behavior were most pronounced approximately 45 to 60 minutes after the drinks. Thus, the study provides objective evidence in young children of a rather subtle, yet significant, time-dependent behavior effect of sucrose ingestion.This research was funded in part by grants from the General Research Grants Committee, University Hospital, Boston University Medical Center, and from the University of Connecticut Research Foundation. The project was conducted at the Clinical Research Center, Massachusetts Institute of Technology (National Institute of Health/General Clinical Research Center Grant 5M01-RR00088-20). We would like to express our appreciation to the many staff members of the Clinical Research Center for their extensive cooperation in helping us to plan and carry out this study, and to the director and staff of Technology Children's Center for their assistance in helping us to reach interested families. We also would like to thank the parents and children who participated in the study. Portions of this paper were presented at the annual meeting of the American Psychological Association, Toronto, August 1984.  相似文献   
90.
The relationship between eye movements and spatial attention   总被引:8,自引:0,他引:8  
Most previous studies of the attentional consequences of making saccadic eye movements have used peripheral stimuli to elicit eye movements. It is argued that in the light of evidence showing automatic “capture” of attention by peripheral stimuli, these experiments do not distinguish between attentional effects due to peripheral stimuli and those due to eye movements. In the present study, spatial attention was manipulated by varying the probability that peripheral probe stimuli would appear in different positions, while saccades were directed by a central arrow, enabling the effects of attention and eye movements to be separated. The results showed that the time to react to a peripheral stimulus could be shortened both by advance knowledge of its likely position and, separately, by preparing to make a saccade to that position. When the saccade was directed away from the most likely position of the probe, the targets for attention and eye movements were on opposite sides of the display. In this condition, the effects of preparing to make a saccade proved to be stronger than the effects of attentional allocation until well after the saccade had finished, suggesting that making a saccade necessarily involves the allocation of attention to the target position. The effects of probe stimuli on saccade latencies were also examined: probe stimuli that appeared before the saccade shortened saccade latencies if they appeared at the saccade target, and lengthened saccade latencies if they appeared on the opposite side of fixation. These facilitatory and inhibitory effects were shown to occur at different stages of saccade preparation and suggest that attention plays an important role in the generation of voluntary eye movements. The results of this study indicate that while it is possible to make attention movements without making corresponding eye movements, it is not possible to make an eye movement (in the absence of peripheral stimulation) without making a corresponding shift in the focus of attention.  相似文献   
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