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191.
192.
Duncan, Ward, and Shapiro (1994) estimated that attention must remain focused on an object for several hundred milliseconds before being shifted to another object, and they referred to this period as theattentional dwell time. An important implication of these long estimates of the dwell time for models of visual search is that the search process must not involve an item-by-item serial scanning mechanism. If it did, then searching through an array of items would require enormous amounts of time, which—based on data from visual search experiments—it does not. The present report, however, provides evidence that the long estimates of attentional dwell time were caused, at least in part, by the use of masked targets. Implications of these variable estimates of the attentional dwell time for models of visual search are discussed.  相似文献   
193.
During linear translation through a stationary environment, the pattern of optical flow generated on each retina is symmetrical when the head is aligned with the heading, but during lateral gaze the optical flow is asymmetric. We assessed whether human subjects could use the magnitude of this asymmetry to determine the direction of heading during passive translation through a 3-D environment. When allowed to move their heads in order to look in the direction of self-motion, subjects indicated their heading precisely and accurately. When the head was locked in alignment with the misaligned body, and gaze adjustments were not allowed, responses were quite precise, but showed a large bias which increased with increasing heading angle.  相似文献   
194.
The present study investigated the validity of an inpatient pain behavior rating scale modified for outpatient use. A series of 43 consecutive outpatients referred for evaluation of chronic pain was examined using the Pain Behavior Scale (PBS) and other psychometric instruments. Analyses revealed significantly higher Pain Behavior Scale scores for low back and multiple pain-site groups. The results also indicated a high degree of internal consistency of the scale. A multiple regression analysis, predicting observed pain behavior from reported pain behavior, indicated that decreased activity accounted for 32% of the variance in the PBS score. A similar regression for pain experience found that the pain level and the sensory scale score on the McGill Pain Questionnaire accounted for 39% of the PBS variance. Psychological characteristics including disease conviction, self-control, depression, and anxiety explained 45% of the variability in the PBS score. Thus, the scale is related to pain intensity, interference with activities, and a variety of psychological characteristics. The scale provides a measure of observable pain behavior that is also relatively independent of these clinical data sources. The Pain Behavior Scale as modified for outpatient use provides a brief index of pain behavior with potential use in the comprehensive evaluation of the pain patient.  相似文献   
195.
A theory is proposed to explain the linkages between individual task goals and performance. Two cognitive constructs are postulated to mediate between task goals and performance:performance expectancy and performance valence. It is asserted that an individual's task goal has a positive influence on performance expectancy and a negative influence on performance valence. Performance expectancy is proposed to have a positive influence on performance while performance valence is proposed to have a negative influence on performance. Task ability is hypothesized to influence performance both directly and indirectly through its influence on performance expectancy. A laboratory experiment was designed to test the causal model proposed by the theory. A path analysis on the data from this experiment provides strong support for the model, with performance expectancy, performance valence, and task ability predicting 63% of the variance in performance on the laboratory task.  相似文献   
196.
A less analytic and more wholistic approach to philosophy, described as ‘best overall fit’ or ‘seeing how things all hang together,’ is defended in recent works by John Rawls and Richard Rorty and can usefully be applied to problems in philosophy of medicine. Looking at sickness and its impact upon the person as a central problem for philosophy of medicine, this approach discourages a search for necessary and sufficient conditions for being sick, and instead encourages a listing of “true and interesting observations” about sickness which reflect the convergence of a number of different viewpoints. Among the relevant viewpoints are other humanities disciplines besides philosophy and the social sciences. Literature, in particular, provides insights into the meaning and the uniqueness of episodes of sickness in a way that philosophers may otherwise fail to grasp.  相似文献   
197.
Personnel representatives (N = 52) were shown one of four videotaped job interviews in which the verbal content of the 16-min interview was identical, but the interviewee's nonverbal behavior was manipulated. A “low nonverbal” interviewee was defined by minimal eye contact, low energy level, lack of affect and voice modulation, and a lack of speech fluency. The “high nonverbal” interviewee demonstrated the opposite behavior on each of these components. The subjects were asked to rate the videotaped candidates on dimensions previously identified as critical in influencing a job interviewer's decisions. Nonverbal behavior was found to have a significant effect on almost every rating made by subjects in this study. After reviewing the entire 16-min interview, 23 of the 26 subjects who saw the “high nonverbal” candidate would have invited him/her for a second interview. All 26 of the subjects who saw the “low nonverbal” candidate would not have recommended a second interview.  相似文献   
198.
This study explored the reasons why professors would leave their teaching/ research occupations to begin new careers as administrators. Valence-Instrumentality-Expectancy theory of occupational preference and choice was used as a framework to examine mid-career change among professors and department chairmen at a major university. Data showed that professors' intentions to change careers and become administrators could be explained by the theory. Analyses of job characteristics demonstrated that professors who want a mid-career change are primarily attracted by the power and formal authority vested in the administrative position, while professors who prefer to remain in their career paths do so because of the autonomy it offers.  相似文献   
199.
The qualitative nature of the incidental memory trace produced by perceptual and conceptual processing within a speeded inference task was examined. Performance on recall and auditory recognition tests replicated the general finding that semantic processing leads to better retention of words than does nonsemantic processing. This pattern of results was reversed on a visual recognition test designed to measure the amount of perceptual information remembered. These data suggest that different types of processing result in different aspects of the stimulus being encoded, with conceptual processing resulting primarily in the encoding of semantic information and perceptual processing resulting primarily in the encoding of physical information. Thus, the effectiveness of a particular kind of processing for good memory performance depends on the kind of information being tested.  相似文献   
200.
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