1987 Fiscal Year Final Research Report Summary
Study on the visual depth perception of low vision children and normally sighted children
| Project/Area Number |
61510059
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
Psychology
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| Research Institution | Japan Women's University |
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Principal Investigator |
TOSHIKO Torii The Institute of Child Study of Japan Women's University. Researcher, 児童研究所, 研究員 (70060671)
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| Project Period (FY) |
1986 – 1987
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| Keywords | Depth Perception / Low Vision / Distance Perception / Size Perception / 距離の推定 / 大きさの推定 |
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| Research Abstract |
Purpose : Visual depth perception was studied on 5 children of low vision(CLV) and 26 normally sighted children(CNV) of 6 years old and 5 normally sighted adults(ANV).
Procedure : 1 Disctimination of the relative depth difference in 3 directions, forward, downward and upward: Two disks of 10cm in diameter or tennis ball were placed on the table in fornt of the subject, on the floor and from the ceiliing respectively. Subject choosed the nrearer of them. 2. Distance Preception: We had him estimate (1) the absolute distance to a disk at various distance on the table.. 3. Size of object: We had him estimate the apparent size of a disk or ball placed at various destance on the tabvle. He reported the perceived size by producing with fingers or drawing.
Results : 1(1) In CLV, threshold of depth difference (<delta>d) measured by depth reception scale was 2-6cm at observation distance of 2m, while 8mm in ANV. The difference was large inbinocular vision at long distance. (2) When actual depth difference of two objects was 1cm, the maximum distance which CLV could discriminate was 1m, 3m in CNV and 8m in CLV in front direction. Discrimination was easiest in forward and next was in upward and Downward was most difficult in CLV. While in ANV, upward was most difficult in discrimination. 2. Accuracy of distance estimation,E=(d-D)/D were ranged within -0.2_+0.2 (Sub.K.I) and -0.4-+0.4 (Sub.K.H.) in CLV, which were larger than that of ANV. 3. The ratio of perceived size(s) at various distance(D) to the standard perceived size (S_0) of an object, was plotted and Gilinsky's equation was spplied. Palameter A was not so different between low vision and normal vision. But, <sigma> was 0.2-4,5 in the children of very low vision, 1.5-9.0 in the children of low vision, 15-30 in the normal children and 30 in the normal adults. That is to say, <sigma> variled depending on visual acuitu.
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