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791.
P. A. Hancock M. Vercruyssen G. J. Rodenburg 《Current psychology (New Brunswick, N.J.)》1992,11(3):203-225
Two experiments are reported which investigated how subject gender and time-of-day influenced the estimation of duration and
the perception of task-related mental workload. In the first experiment, 24 subjects performed a filled time-estimation task
in a constant blacked-out, noise-reduced environment at 0800h, 1200h, 1600h, and 2000h, respectively. In the second experiment,
12 different subjects performed an unfilled time estimation task in similar conditions at 0900h, 1400h, and 1900h. At the
termination of all experimental sessions, participants completed the NASA Task Load Index workload assessment questionnaire
as a measure of perceived mental workload. Results indicated that physiological response, reflected in body temperature change,
followed an expected pattern of sequential increase with time-of-day. However, estimates of duration and the perception of
mental workload showed no significant effects for time-of-day. In each of the experiments there were significant differences
in time estimation and mental workload response contingent on the gender of the participant. These results are interpreted
in light of the previous positive findings for circadian fluctuation in performance efficiency and the equivocal findings
of a gender difference in time estimation. A unifying account of these collective results is given based on gender by time-of-day
interactional effects.
An earlier version of this paper was presented at the 32nd Annual Meeting of the Human Factors Society, Anaheim, CA, October,
1988. 相似文献
792.
793.
M H Huang S S Hull R D Foreman R Lazzara S Wolf 《Integrative Physiological and Behavioral Science》1992,27(1):6-12
The shortening of the QT interval of the electrocardiogram coincident with acceleration of heart rate and vice versa has been accepted for many years as evidence that the action potential duration and hence QT are necessarily dependent on heart rate. Exceptions to this rule have been attributed to the intervention of counteracting autonomic effects. In order to test this assumption, 26 conscious dogs divided into three groups were tested during baroreceptor stimulation by a bolus injection of phenylephrine. Seventeen dogs had been used in earlier studies in which they had undergone an experimental anterior myocardial infarction with apparent full recovery. A group of those dogs underwent beta-adrenergic blockade by intravenous atenolol 30 min prior to the baroreceptor activation. To test the intactness of the baroreceptor responses in the previously infarcted dogs, a third group of nine dogs that had had no prior myocardial infarction was included. All dogs were adapted to the laboratory environment and were not sedated during experiments. Simultaneous recordings of RR, QT interval, and phasic arterial pressure were made in all dogs before and during baroreceptor stimulation. In the normal group, and the previously infarcted group that received no atenolol, baroreceptor stimulation elicited a small (8/msec), but significant prolongation of the QT associated with a nearly 50% reduction in heart rate. The QT interval of the atenolol-treated dogs, although significantly more prolonged before stimulation, remained unchanged during the reflex. The data indicate that withdrawal of ventricular sympathetic tone may prolong the QT interval, thereby confirming the role of sympathetic innervation in the control of QT.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
794.
A number of investigators have suggested that affective states influence the focus of attention. One recent proposal is that negative moods increase self-focus. This review considers the evidence that bears on this hypothesis. Conceptual issues pertaining to the construct of self-focus are discussed first. Next, the various parameters that influence attentional focus are presented in order to provide a way of organizing the mood/selffocus literature. Studies that have used state measures of mood and self-focus are considered in this context. Methodological limitations of existing studies are discussed and directions for future work provided. 相似文献
795.
Quantification of a chaotic system can be made by calculating the correlation dimension (D2) of the data that the system generates (Packard et al., 1980). The D2 algorithm, however, requires stationarity of the generator, a feature that biological data rarely reflect (Mayer-Kress et al., 1988). So we developed the "point correlation dimension" (PD2), an algorithm that accurately tracks D2 in linked data of different dimensions (Carpeggiani et al., 1991). We now present a mathematical argument that, for stationary data, individual PD2s converge to D2 and we demonstrate that the algorithm rejects contributions made by bursts of noise. Data were obtained from the surface of the olfactory bulb of the conscious rabbit (64 electrodes, 640 Hz each, 1.3 sec epochs) before and after presentation of a novel or habituated odor. D2 could be calculated in only 1 of 10 novel-odor trials, whereas PD2 could be calculated in all. Both algorithms indicated that a novel odor evokes a spatially uniform dimensional increase. The PD2 uniquely exhibited the dimensional decreases that occur during inspiration and the gradients of mean dimension present during the nonstimulated control state. These control gradients remained unchanged without odor experience, but showed spatially specific PD2 increases following odor habituation. It is interpreted that, 1) the PD2 is sensitive, accurate, and appropriate for dimensional assessment of biological data, 2) that during analysis of unfamiliar information a single global process is transiently evoked in the neuropil, and 3) after experience multiple spatially specific processes tonically map the sites of learning. 相似文献
796.
This study of 20 ‘white-collar’ workers aged 20–30 measured motivation, enjoyment and access to various categories of experience in both work and leisure, and examined their relationship with psychological well-being on a number of dimensions. The method used a short questionnaire, psychological scales and the innovatory ‘experience sampling methodology’ (ESM) where respondents answer questions in a diary on the receipt of a signal from a pre-programmed watch or radio pager eight times a day for 1 week. The results show, in line with other studies, that intrinsic motivation in daily life is correlated with happiness but that, not previously reported, when motivation at work is examined both extrinsic motivation and instances where a person had to do the activity but did not wish to be doing something else, i.e. ‘positive motivational change’, are correlated with positive aspects of psychological well-being, while instances where a person wanted to do the activity but wished to be doing something else, i.e. ‘negative motivational change’, correlated with negative aspects. The results also show that enjoyment in both work and leisure correlates with aspects of psychological wellbeing; and that macro ‘flow’ experiences, where high skills and high challenges are perceived as equal, are enjoyable and interesting and come primarily from work. The study also shows that categories of experience considered important for psychological well-being and deemed to come primarily from work can be obtained in leisure. The results are discussed in the context of person—situation interactions and processes, and it is advocated that these should be studied in a variety of samples. 相似文献
797.
John W. Schuster Ed.D. Ann K. Griffen B.S. Mark Wolery Ph.D. 《Journal of Behavioral Education》1992,2(3):305-325
Simultaneous prompting (a type of antecedent prompt and test procedure) and constant time delay were compared with four students with moderate mental retardation learning expressive sight words. A parallel treatments design across word sets and replicated across students was used. For acquisition, the simultaneous prompting procedures required fewer trials, sessions, and training time to criterion and resulted in fewer student errors during daily probe and training sessions. However, maintenance data indicated mixed results across the two procedures. Reliability data (both dependent and independent variables) revealed no differences between the two procedures in terms of the teacher's accuracy in recording student responses and implementing each procedure. Future research issues are discussed. 相似文献
798.
We assessed the effects of a computerized matching-to-sample procedure on the spelling performances of three students with mental retardation. Initially, the students could 1) match pictures and printed words to one another, and 2) match pictures and printed words to spoken words. However, they could not construct words to either pictures or spoken words (e.g., touch, in order, the letters s->h->o->e given the spoken-word sample Shoe). Word constructions then improved markedly after exposure to delayed constructed-response identity matching (e.g., touch the letters s->h->o->e given the printed-word sample shoe). One subject's oral and written spelling also improved. The results extend previous research by showing multiple positive effects of a computerized spelling intervention. These effects may have occurred in part because of the formation of stimulus classes among pictures, printed words, and spoken words. 相似文献
799.
The field of applied behavior analysis has devoted considerable effort to the problem of educating America's youth. In addition to developing a wide range of procedures to improve children's academic and classroom survival skills, behavioral researchers have discussed a wide range of technological characteristics that are likely to facilitate the adoption of their procedures by educational decision-makers and practitioners. A movement to restructure American schools has become highly popularized within educational, political, and public media forums over the past several years. One general characteristic of this movement is its failure to recommend the more frequent implementation of applied behavior analysis techniques to educate America's youth. A close inspection of three global models for school reform, however, reveals notable compatibilities with the focus and goals of applied behavior analysis. Applied behavior analysts can collaborate with and contribute to the school restructuring movement by pursuing the more formal and systematic analyses of characteristics essential to the adoption process. 相似文献
800.