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991.
Computing stress     
This article is based on a review of recent literature on “computing stress”; that is, on the psychological stress effects of working with computer systems. Current research into the sources of computer-related stress has tended to concentrate on those employees who operate Visual Display Units (VDUs), either on a full-time professional basis as word-processor (WP) operators, data-entry clerks, secretaries, or those dealing with enquiries from the public; or employees who use the VDU irregularly as part of their other duties. A few studies have looked at specific occupation groups, such as printers (Kalimo & Leppänen, 1985), information technology professionals (programers and analysts), process workers, and college students (Sproull, Kiesler, & Zubrow, 1984). Generally, however, research has been carried out on office workers, more often women, carrying out administrative tasks. An attempt is made to identify those potential work-related stressors that have been isolated by these studies, and also included are criticisms of the general methodologies used in many of them.  相似文献   
992.
The purpose of the present experiment was to investigate the efficacy of a goal orientation procedure in their treatment of apathy, isolation, and insufficient goal setting skills in chronic psychiatric residents. The experiment was conducted in a behaviorally-oriented deinstitutionalization program in a state psychiatric hospital. Three male and four female chronic psychiatric residents served as research participants. A group repeated measures design with four within-participant phases (ABA‘B’) was utilized. The goal orientation procedure included a written schedule that was completed by each research participant daily. This Daily Living Schedule required that a behavior be specified by the participant for every half-hour period during the day (8:30 a.m. to 9:00 p.m.). During all four phases of the experiment, research participants were observed on the ward from 8:30 a.m. to 12:00 noon and 1:00 p.m. to 5:00 p.m. for engagement in scheduled target behaviors. The daily scheduling procedure produced substantial increases in appropriate behavior such as social activities, ward jobs, and participation in treatment programs, whereas decrease were produced in inappropriate behavior such as isolation and day time sleeping.  相似文献   
993.
Modifications and corrections to Rayfield’s (1982) assembly language routines for data acquisition and experimental control using the Apple II computer are described. The modified routines, together with an optoisolated hardware interface, provide a reliable, accurate, and easy to use microcomputer system for experimental control and data acquisition.  相似文献   
994.
Gardner, Dalsing, Reyes, and Brake (1984) supplied a table of criterion values (β) related to hit and false-alarm rates in signal detection theory. Other methods of calculatingβ are suggested as more accurate alternatives to using that table. A short computer program is provided to calculate β and the sensitivity indexd’.  相似文献   
995.
996.
Forty normotensive subjects participated on a voluntary basis in a study designed to compare the effect of suggestions on blood pressure (BP). Two experimental groups received suggestions presumed to be specific in lowering or raising BP after simple relaxation (relaxation group) or hypnotic induction (hypnotic group). A control group was used to record the BP changes over time. The time variable was significant for both systolic (SBP) and diastolic blood pressure (DBP). Induction procedures (hypnosis or relaxation) resulted in significant decreases in DBP in both experimental groups. In the control group there was a significant decrease in SBP. A specific suggestion to increase the BP resulted only in DBP increase in the hypnotic group. This group also gave an increase of both SBP and DBP over the entire experiment, whereas the relaxation group resulted in a significant decrease in SBP. There was no significant group variable, indicating no differences between the groups. Further research is needed to enable firm conclusions of the effect of suggestions on BP.  相似文献   
997.
This study evaluated the relative efficacy of long (1 minute) and short (15 seconds) durations of negative practice for reducing self-stimulatory leg pounding of a traumatically brain-injured adult. In individual social skill training classes, long negative practice and short negative practice were administered concurrently in an alternating treatments design. Generalization of treatment effects outside of training sessions was assessed during the client's lunch period. The results revealed that both durations of negative practice were equally effective in reducing leg pounding during training sessions. However, the effects of training did not generalize to settings in which the practice contingency was not enforced. Pounding was more frequent and negative practice somewhat less effective during periods of high social stimulation.  相似文献   
998.
Alternate monocular and binocular exposure to complementary stimulation can yield opposite but coexisting aftereffects that are contingent on whether the test display is viewed with one eye or two eyes. The motion aftereffect was studied by adapting each eye separately to a contracting spiral and both eyes together to an expanding spiral. The stationary test spiral subsequently appeared to be expanding when viewed monocularly, but to be contracting when it was seen with both eyes open. With respect to the McCollough effect, after monocular exposure to red-vertical and green-horizontal gratings and binocular exposure to red-horizontal and green-vertical gratings, the appearance of the color of the test gratings when viewed with one eye was different from that when viewed with both eyes. Opposite, coexisting aftereffects induced by complementary stimulation can be interpreted as evidence that there are unique binocular aspects to visual function.  相似文献   
999.
This study investigates the separate activation versus coactivation issue for redundant targets in a simple letter-detection paradigm with latency as the dependent variable. The results of a one-response visual-search task are reported. Since, on single-target trials, only the target was presented and no accompanying noise element, no “distraction decrement” caused by irrelevant noise elements (Grice et al., 1984) was to be expected. The data obtained showed a clear redundantsignal effect. Subsequent detailed analysis of the latency data using Miller’s (1982) procedure indicated that the results were consistent with a separate activation model and failed to provide convincing evidence in favor of coactivation models. A further analysis of the data indicated that, in the present study, the separate channels were negatively correlated for a range of fast RTs and positively correlated for intermediate and larger RTs. No evidence in favor of Grice et al.’s (1984) distraction-decrement hypothesis was found. The conclusions of this study are that (1) a separate activation model summarizes the essential features of information processing in this simple visual search task, and (2) no convincing evidence in favor of coactivation in visual search tasks has been reported in the literature up to now.  相似文献   
1000.
A McCollough effect was induced in subjects by having them view typical adapting stimuli binocularly for 5 min. In the control condition, the strength of the McCollough effect was measured 20 min after the end of the adaptation. The strength was measured during monocular and binocular viewing of a test pattern via a color cancellation technique. Monocular strengths for the two eyes of a given subject were equal to each other and slightly weaker than the binocular strength. In the test condition, 15 min of the 20 min between adaptation and testing were spent monocularly viewing black and white gratings of the same orientation and spatial frequency as the adapting gratings. The strength of the effect as measured ipsilaterally was markedly decreased from that in the control condition. The strength of the effect as measured with the contralateral eye showed only a small decrease from that of the control condition. This finding is relevant to various models of the McCollough effect and related color aftereffects, especially those that posit a “learning” type of mechanism between achromatic spatial channels (which exhibit clear interocular transfer of various achromatic effects) and monocular color channels.  相似文献   
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