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991.
In two experiments, the pattern of persistence of negative priming effects across delay intervals of 500 and 2,500 msec was assessed using a within-subjects, random sequencing of delays. Neill and Valdes (1992; Neill, Valdes, Terry, & Gorfein, 1992) have argued that a within-subject experimental design is required for decay of negative priming to be seen, in contrast to results reported elsewhere (e.g., Tipper, Weaver, Cameron, Brehaut, & Bastedo, 1991) showing stable negative priming effects across delays. In neither experiment was substantial evidence of decay detected, raising questions for the notion that suppression necessarily declines across brief temporal intervals and for the assertion that episodic retrieval is the sole source of negative priming.  相似文献   
992.
We investigated the ability of subjects to discriminate sugars with a whole-mouth forced-choice paradigm, in which a standard solution was compared with a test solution of varied concentration. Discrimination probabilities were U-shaped functions of test concentration: for 6 subjects and pairwise combinations of fructose, glucose, and sucrose, discriminability always declined to chance over a narrow range of test concentrations. At concentrations ≦ 100 mM, maltose was indiscriminable from fructose but discriminable at higher concentrations for 4 subjects. By analogy with themonochromacy of night vision, whereby any two lights are indiscriminable when their relative intensities are suitably adjusted, we call the gustatory indiscriminability of these sugarsmonogeusia. The simplest account of monogeusia is that all information about the indiscriminable sugars is represented by a single neural signal that varies only in magnitude. The discriminability of maltose from the other sugars at higher concentrations is consistent with the hypothesis that maltose also activates a second gustatory code.  相似文献   
993.
‘The authors discuss the dynamics of suicide, how to work with a potentially suicidal client in the counseling relationship, and legal and ethical implications for the counselor.  相似文献   
994.
There are several studies suggesting that the Social Performance Survey Schedule (SPSS) is a reliable and valid measure of social skill. However, the factorial structure of the SPSS has never been examined. In the present study, SPSSs taken by 652 college students were factor analyzed by the method of principal components and the resulting factors were rotated according to the varimax criterion. Separate factor analyses were conducted for men and women. Seven factors, which accounted for a little over a third of the total variance, were retained for each sex. A large general factor labeled Prosocial Competence emerged for both sexes. Beyond this, the factorial solutions for the two sexes tended to diverge, with males showing a large negative factor (Social Offensiveness) and three smaller negative factors and females showing five relatively small negative factors. Suggestions were made concerning additional factor analytic studies of the SPSS and the ways in which derived factors might be used in research and clinical work.This research was supported by funds from the Rutgers University Research Council. Thanks are due to Leona Aiken for her statistical consultation.  相似文献   
995.
This study was designed to provide a detailed analysis of the parameters which interact to produce a field hockey drive. The drive was performed by an elite performer under two conditions of uncertainty (Blocked and Random). The subject was asked to drive a field hockey ball toward a specified target. In the Blocked condition the speed of the approaching ball remained constant (20, 30 and 40 m.p.h.) while in the Random condition these speeds were randomly assigned to each trial. Cine analysis of the subject's successful responses under the two experimental conditions led to an investigation of the kinematics, phasing, and timing of the stroke. The subject placed emphasis upon varying the initial phases of the stroke (i.e., backswing and preparatory phases) in order to produce a temporally consistent ballistic downswing to ball contact. It seemed likely that the subject appraised the ball speed that was being delivered and then incorporated additional stick movement to ‘mark time’ before initiating temporally consistent movement phases, as spatial uncertainty increased, the subject delayed her response initiation, but then tended to respond in intervals of one reaction time for each stroke phase. Consistency was evident for displacement and initiation point values, but to a lesser extent than existed for the other variables. However, as a result of this adjustment in spatial location and displacement of the stick end during the preliminary phases of the response, the subject was able to produce a consistent and accurate ballistic downswing.  相似文献   
996.
997.
The relationship between entertainment activity preference and sensation-seeking was investigated by survey and actual movie selection and viewing. Cardiac rate and rate change was monitored during movie selection and viewing. High sensation-seeking (HSS) females reported preferences for activities centered about alcohol, sexually-explicit materials and ‘rock’ music. HSS males reported preferences for sexually-explicit materials and news/documentary reports. Low sensation-seeking (LSS) males and females reported preferences for the musical stage, theatrical drama and comedy, and romantic/dramatic novels. HSS males and HSS females allotted high proportions of viewing time to an ‘action’ movie, and changed channels more frequently than LSS. The indices of cardiac response utilized in this study were unrelated to movie viewing activities, a result which does not support the ‘optimal level of arousal’ view of sensation-seeking proposed by Zuckerman (1979).  相似文献   
998.
Medical students pose as physicians during clinical training. This article presents three cases where students justify misrepresenting their status for different reasons: self-concern for career, necessity for clinical training, and belief that the truth could cause undue psychological stress in the patient. The author suggests that serious consequences of this practice should be constantly reviewed in a critical light.  相似文献   
999.
1000.
Cornell University Medical College, Westchester Division, The New York Hospital, White Plains, New York It is well established that there is a complex timekeeping mechanism in the human brain. This mechanism is associated with a variety of physiological and psychological rhythms having a period of about a day, and thus referred to as circadian rhythms. The circadian system has recently been modeled in terms of two underlying oscillators, one much more resistant to changes in routine than the other. These oscillators are considered to be endogenous, that is, internal to the organism, and not reliant for their existence upon changes in the person’s environment or general behavior. They thus continue to run even when the sleep/wake cycle is suspended, as in sustained operations. Thus, by their very nature, sustained operations require the individual to override the inputs that are coming from his or her circadian system (especially the indication that sleep is required). The aim of this paper is to provide a background to the area of circadian rhythms research, including a section on the methodology, so that the impact of the circadian system on sustained operations can be better understood.  相似文献   
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