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111.
Perception of translational heading from optical flow 总被引:3,自引:0,他引:3
W H Warren M W Morris M Kalish 《Journal of experimental psychology. Human perception and performance》1988,14(4):646-660
Radial patterns of optical flow produced by observer translation could be used to perceive the direction of self-movement during locomotion, and a number of formal analyses of such patterns have recently appeared. However, there is comparatively little empirical research on the perception of heading from optical flow, and what data there are indicate surprisingly poor performance, with heading errors on the order of 5 degrees-10 degrees. We examined heading judgments during translation parallel, perpendicular, and at oblique angles to a random-dot plane, varying observer speed and dot density. Using a discrimination task, we found that heading accuracy improved by an order of magnitude, with 75%-correct thresholds of 0.66 degrees in the highest speed and density condition and 1.2 degrees generally. Performance remained high with displays of 63-10 dots, but it dropped significantly with only 2 dots; there was no consistent speed effect and no effect of angle of approach to the surface. The results are inconsistent with theories based on the local focus of outflow, local motion parallax, multiple fixations, differential motion parallax, and the local maximum of divergence. But they are consistent with Gibson's (1950) original global radial outflow hypothesis for perception of heading during translation. 相似文献
112.
Interactions between area and numerosity 总被引:2,自引:0,他引:2
Piet G. Vos Michiel P. van Oeffelen Hein J. Tibosch Jüri Allik 《Psychological research》1988,50(3):148-154
Summary The concept of filled area, i.e. the impressionistic ensemble of parts of a stimulus field occupied by dots, is used to account for various kinds of numerosity illusions due to perceptual interaction between a number of dots and their spatial arrangement. A measure of filled area is derived from a model for the perceptual clustering of dots on the basis of relative proximity. It is shown that the quantified concept of filled area successfully predicts illusion data from earlier studies. Subsequently, a two-alternatives forced-choice numerosity experiment is reported, the data of which gave further evidence of the predictive power of the filled-area hypothesis. Our approach is discussed with respect to spatial features of dot stimuli that might be in rivalry with the filled-area factor in numerosity-estimation tasks. 相似文献
113.
U W Huck R D Lisk E J Parente 《Journal of comparative psychology (Washington, D.C. : 1983)》1988,102(4):388-391
After 12-15 ejaculatory series, each consisting of several short intromissions (2- to 3-s vaginal penetration) and an ejaculation, male golden hamsters adopt an altered copulatory pattern consisting of long intromissions (5- to 25-s penetration with intravaginal thrusting). Receptivity declines and the tendency for the female to attack the male increases at about the time of this shift in copulatory pattern. Because the mean interintromission interval (III) between short intromissions is about 8 s compared to 100 s between long intromissions, it is possible that females detect this difference and adjust their mating accordingly. When the III between short intromissions from a rested male was experimentally increased to 100 s by use of a halter and lead device, the duration of lordosis was significantly less than that displayed by females paired with control males (8-s III) and virtually the same as that displayed by females paired with males that produced only long intromissions. This suggests that the female uses the temporal patterning of intravaginal stimulation as one criterion for terminating mating with a particular male. 相似文献
114.
The authors discuss the results of a study designed to assess nationally certified counselors' perceptions of the relevance of elements of the National Board for Certified Counselors examination to their work as counselors. Support for the validity and appropriateness of the examination in regard to perceived relevance and lack of differentiation on the basis of respondent characteristics were found. 相似文献
115.
Bonaparte, G., Chapman, J., & Steinberg, J. (1987). Michigan: Two career guidance models. Vocational Education Journal, 62(6), 142–143. Greenwood, K. (1987). Counseling adults in career transition. Vocational Education Journal, 62(6), 44–46. Herr, E.L. (1987). Comprehensive career guidance and vocational education: Natural allies. Vocational Education Journal, 62(6), 30–33. Lambert, R. (1987). A guide to career information. Vocational Education Journal, 62(6), 34–36. Lester, J.N., & McCormac, M.E. (1987). The NOICC career guidance standards project. Vocational Education Journal, 62(6), 47–48. Otto, L.B. (1987). Parents: Key advisors. Vocational Education Journal, 62(6), 37–38. 相似文献
116.
117.
Age differences in short-term retroactive interference, unconfounded with age differences in rehearsal in the retention interval of the Brown-Peterson Task, were not found in a cross-sectional study of adults 18-32 and 64-78 years of age. Degree of retroactive interference was manipulated conjointly with distractor interval length (0-15 s). Individual memory span was assessed and used as the list length in order to achieve stimulus equivalence of memory loads across individuals and age groups. An attention-demanding matching task that adjusted itself in difficulty to the individual's attentional capacity was used as the distractor activity. Covert rehearsal during the retention interval was inferred using several measures, including a comparison of distractor task performance in the presence and in the absence of a memory load, and rehearsers were excluded from the primary analyses. We conclude that there is no interference proneness with increasing age in the present study. 相似文献
118.
Harald Merckelbach Marcel A. van den Hout Anita Jansen G. Margo van der Molen 《Journal of psychopathology and behavioral assessment》1988,10(4):355-366
The nonrandom distribution of situational fears has been explained by evolutionary survival relevance of specific fears. Thirty-eight stimuli were taken from the literature on preparedness and were scored on fearfulness, objective dangerousness, and spatiotemporal unpredictability by three separate groups of students. The same items were scored on survival relevance by 15 biologists. Fearfulness of cues significantly correlated not only with survival relevance but also, and even more strongly, with dangerousness and unpredictability. While the fear/survival relevance association virtually disappeared when the unpredictability contribution was partialed out, the fear/unpredictability correlation was only marginally affected when controlling for survival relevance. This suggests that nonrandomness of feared stimuli may result from the spatiotemporal unpredictability that is attributed to these stimuli. The current practice of using snakes and spiders as phobia-relevant, and flowers and mushrooms as neutral, cues was not justified by the ratings of the 15 independent experts.This study was supported in part by a grant from the Dutch Organization for Fundamental Research (ZWO/Psychon, 560-268-001). 相似文献
119.
Young and older adults were presented with pictures for study. Their recognition of the information was tested at five retention intervals: immediately, and 48 hr, 1 week, 2 weeks, and 4 weeks later. The main finding of interest was that picture recognition did not show an age-related decline until the 1-week retention interval. 相似文献
120.