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61.
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 & Lepp?nen, 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. The terms “visual display unit,” “visual display terminal,” VDU, VDT, and “terminal” are used interchangeably.  相似文献   
62.
Brief presentations of letter arrays were probed by bar markers within or outside the fovea after various time delays. Figural information presented to the foveal region was retained better under a photopic condition than information in the parafoveal region, but under a scotopic condition parafoveal information demonstrated superior retention. However, decay rates over time of all functions were similar, demonstrating that figural information in the rods and cones decays at similar rates.  相似文献   
63.
64.
Induction by reinforcer schedules.   总被引:1,自引:1,他引:0       下载免费PDF全文
Traditional strategies for determining whether a reinforcer schedule enhances the occurrence of an activity are reviewed and critically evaluated. A basic assumption underlying these strategies is that it is possible to isolate the effect of reinforcer intermittency on schedule induction. It is concluded that this is not, in fact, possible. An alternative approach is proposed that emphasizes the inductive effects of the reinforcer schedule as a unit and the effects of particular aspects of the reinforcer schedule (e.g., interreinforcer interval, repetition of the reinforcer, reinforcer magnitude).  相似文献   
65.
Smokers and nonsmokers were compared on three aspects of academic achievement. Although exactly the same percentage of smokers and nonsmokers passed the first-year university examination, smokers obtained significantly higher marks. Similarly, smokers achieved significantly higher marks in their final year examinations in comparison with nonsmokers. Finally, a comparison of the tutorial essay marks of the smokers and nonsmokers again showed that smokers obtained significantly higher marks than nonsmokers. These data are consistent with the idea that ambitious students adopt smoking in the belief that it will help them study and sustain concentration.  相似文献   
66.
67.
The application of 360° videos raised the attention of educators and researchers, as it appears to be an approachable option to mediate complete environments in educational settings. However, challenges emerge from the perspective of educational psychology. Learning irrelevant cognitive strains might be imposed because it is necessary to navigate through spherical material. However, these potential downsides could be compensated for using signaling techniques. In a two (macrolevel vs. no macrolevel signaling) × two (microlevel vs. no microlevel signaling) factorial between-subjects design plus control group, 215 fifth-and sixth-grade students will watch a 360° video about visual and behavioral characteristics of animals. Learning outcomes, cognitive load, disorientation, and presence will be investigated. It is expected that macrolevel signaling will enhance learning and presence and reduce cognitive load and disorientation. Microlevel signaling will have comparable advantages, but these effects will be more pronounced when macrolevel signaling is implemented.  相似文献   
68.
The detection of visual intensity differences by pigeons   总被引:1,自引:1,他引:0       下载免费PDF全文
Pigeons were trained in a conditional discrimination procedure to discriminate between visual stimuli that varied in intensity. The magnitude of the intensity difference ranged from 0.80 to 0.05 logarithmic units. Psychometric functions were calculated from the data and the mean difference threshold for the 11 subjects was approximately 0.12 logarithmic units. A signal-detection analysis of the data suggested that stimuli that were below the calculated threshold were detectible to the subjects.  相似文献   
69.
Nine subjects, 14 to 18 yr old, pulled a knob on a schedule of monetary reinforcement. Concurrently, they escaped or avoided periodic presentations of a tone by pressing a button that required 1.5 lb (6.67 N) of force or by punching a padded cushion that required 20 lb (88.96 N) of force. The punching response was designated as an aggressive response because the force of this response together with its topography was comparable to responses of humans that deface objects and produce escape or counter aggression from other humans. It was found that button pressing was the preferred concurrent avoidance response and there were few punches. However, when the monetary reinforcer was discontinued (extinction) punching increased for seven of the nine subjects, but there was no consistent change in the rate of button pressing. When the punching response was replaced by another non-preferred but non-aggressive response, neither this response nor button pressing increased during extinction. Hence, the increase in punching during extinction cannot be attributed solely to the fact that it was a concurrent response or a non-preferred response.  相似文献   
70.
Squirrel monkeys were restrained in a chair equipped with a tail-shock apparatus and a pneumatic bite hose located in front of the subject's face. An aggressive response was recorded when the monkey bit the hose. Initial sessions in which no shocks were delivered produced some biting. When biting during these sessions stabilized at a near-zero level, regularly scheduled shocks were delivered to the monkey's tail, causing a consistently higher rate of biting. After several sessions under these conditions, a punishment phase was introduced in which the previous shock conditions were maintained, and every bite was followed immediately by another, more intense shock. Biting under these conditions was suppressed to a near-zero level. When the punishment contingency was removed, biting increased. With one subject, two additional bite-contingent stimuli were examined: (1) a milder shock that, when made contingent upon hose biting, also suppressed that response, and (2) a contingent tone that had no obvious suppressing or facilitating effect. Individual differences among subjects were extreme, but the effect of bite-contingent shock was consistent. Observations of the subjects during the punishment sessions indicated the existence of certain side effects that resulted from the use of punishment to suppress shock-induced aggression.  相似文献   
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