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The perception of distance and size in the presence of optical gradient information was investigated under four viewing conditions—binocular view with and without head motion, and monocular view with and without head motion. Subjects (60 adults) matched distance intervals (from 15 to 127 cm) and heights of a target triangle (from 5 to 15 cm) by adjusting the length of a metal tape. Both linear and power functions were fitted to each individual’s distance judgments, and the competing perceptual models were compared. For both models, it was found that binocular information was sufficient to specify relative, but not absolute, distance, that monocular information was sufficient to specify an orderly relation between target distance and judgment but not absolute distance, that average error was less in the binocular conditions, and that perceived distance was not affected in either condition by the addition of head motion. The analysis of size judgments revealed that monocular and binocular judgments did not differ, that matches made with and without head motion did not differ, and that, in all conditions, matches exceeded target heights by an average 30% to 40%. Judged size was also analyzed as a function of target distance. In all conditions but monocular view with head motion, the effect of distance was to increase size judgments. The distance judgments support the hypothesis (Purdy, 1958) that the binocular stimulus carries information that the monocular stimulus does not; they fail to support the hypothesis (Gibson, 1966) that observer motion adds information to the static stimulus. The size judgments support neither hypothesis but suggest an independence of perceived size from perceived distance.  相似文献   
74.
The development of automatic word recognition as a function of reading skill was investigated in three experiments using the Stroop task. Reading skill level ranged from nonreaders to readers above the sixth-grade equivalent. Interference with color naming begins to emerge early in the process of learning to read, increases, and then subsequently decreases. Strings of identical letters delayed color naming for children just beginning to learn to read. The interference from words, presumably reflecting semantic processing, began developing early but did not peak until the second- to fourth-grade reading levels. These different sequences of development of interference in the various stimulus conditions suggest that word recognition is the result of a number of component processes that develop as children acquire skill in reading.  相似文献   
75.
If spatial memory tasks are considered as foraging problems, it can be predicted that rats' difficulty in learning a win-stay task—revisiting part of a maze where food has recently been found—should be partly overcome if the food is not fully consumed at the first visit (nondepleted reward) rather than being all eaten (depleted reward). Three experiments confirmed and further analysed this result. Experiments 1 and 2 showed that it does not depend on the amount of food initially found; nor is win-stay performance affected by the amount of food actually eaten. Experiment 3 suggested that the effects of nondepleted reward are mainly due to the animals' being interrupted while eating, and very little to the fact that uneaten food is left behind. The results are discussed with regard to their implications for learning theory, and for the application of foraging theory to learning and memory experiments.  相似文献   
76.
Gardiner and Gregg (1979) showed that in a free-recall paradigm in which each list word is embedded in a continuous stream of subject-vocalized distractor activity, recency recall was greater when the words were presented auditorily rather than visually. The experiment described here showed that this auditory advantage persisted even when list and distractor items were both spoken at a controlled pace by the experimenter, and that it was little influenced by instructions to give priority in recall either to the beginning or to the end of the list. These results strengthen the conclusion that this effect cannot be accommodated by any echoic memory theory and, because the effect was not enhanced when prerecency items were recalled first, demonstrate an additional difference between it and the somewhat similar auditory advantage found in immediate recall.  相似文献   
77.
Subjects decided whether two dots were on the same curve or on different curves in patterns consisting of two curves and two dots in displays that had an exposure duration of 200 msec or that remained in view until the subjects' response. The overall size of the patterns was varied by a factor of two. Furthermore, across experiments, we manipulated the predictability of the size of the pattern on a particular trial. On half of the trials, the two dots were on the same curve; across these trials, the distance between the dots, along the curve, was manipulated systematically while the Euclidean distance between the dots was held constant. On the other half of the trials, the two dots were on different curves. The time to respond same increased monotonically as curve distance between the dots increased, suggesting that subjects mentally traced the curve in order to perform the task. The absolute size of the pattern had little or no effect on the response times, indicating that it was curve distance relative to the overall pattern size, rather than absolute distance, that controlled response times. Furthermore, expectancies about pattern size had essentially no effect on performance. Taken together, the results suggest that the rate of tracing is determined by various stimulus properties that covary with the overall size of the pattern on which tracing takes place, such as the distance between the traced curve and nearby distractor curves, or the curvature of the traced curve.  相似文献   
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Rapid growth has been observed in recent years in the number of women entering traditionally male blue-collar occupations, yet researchers have paid little attention to this pioneering group. The present study undertook a comparison of the job conditions of two groups of nontraditional women workers, tradeswomen (N=71), and transit workers (N=151); a third group, school secretaries (N=389), was studied as a comparison group of traditionally female workers. Results from a 16-page mail questionnaire revealed that women in traditionally male occupations encountered significantly more adverse working conditions than did their traditional counterparts, and, in addition, reported significantly less satisfaction and more stress at work. Tradeswomen were the most likely to experience sexual harassment and sex discrimination, and black tradeswomen to experience race discrimination. The degree of job satisfaction expressed by the secretaries was unexpected, since most evidence suggests that clerical workers lack autonomy, and encounter boredom and routinization on the job. These findings are discussed in terms of gender segregation and the need to focus future research efforts on specific occupational groups in order to make appropriate policy recommendations as well as to provide help for women in these jobs.This research was supported by grants from the National Institute for Occupational Safety and Health (Grant No. 1 RO1 OH02162-01A1) and the College of Health and Human Development, The Pennsylvania State University. The authors wish to acknowledge the invaluable contributions of Patty Lambert, Ming Qi Wang, Mary Harmon, Joseph Vasey, Gina Jay, Darrell Harvey, and Haleh Rastegary.  相似文献   
80.
This study explored the contributions of role stressors and personal resources in predicting strain symptoms experienced by 117 professional women employed full-time in academia. Results of multiple regression analyses revealed that, while role stressors alone accounted for only a moderate amount of the variance in reported strain symptoms, 51 % of the variance was explained when both stressors and personal resources were combined. Womend, who experienced higher levels of personal control and social support as well as a greater number of roles occupied reported lower levels of strain symptoms. These results support the use of a transactional model of stress in future multiple role research.  相似文献   
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