Psychophysiological Study for Depth Perception

Research Project

Project/Area Number	61510072
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	Psychology
Research Institution	Tokyo Metropolitan Institute for Neurosciences
Principal Investigator	YAMAGUCHI Kiyoko Tokyo Metropolotan Institute for Neurosciences,Researcher, 医学心理学部門, 主事研究員 (10073090)
Co-Investigator(Kenkyū-buntansha)	OKUDA Hiroki Tokyo Metropolitan Institute for Neurosciences,Researcher, 医学心理学部門, 主事研究員 (90177171)
Project Period (FY)	1986 – 1987
Project Status	Completed (Fiscal Year 1987)
Budget Amount *help	¥1,300,000 (Direct Cost: ¥1,300,000) Fiscal Year 1987: ¥500,000 (Direct Cost: ¥500,000) Fiscal Year 1986: ¥800,000 (Direct Cost: ¥800,000)
Keywords	Depth Perception of Monkey / Uniform Visual Field / Inferior Parietal Cortex / 前頭葉弓状溝領野
Research Abstract	The purpose of this study is to examine whether the fromtal prearcuate cortex or the inferior parietal cortex of monkey is concerned with the depth perception.Before and after operation,monkeys were tested for their reactions to the raisins presented at ten different distances (5 positions within reach and 5 positions beyond reach) in a uniform visual field.In a uniform visual field,monkey had to judge the distance to the raisin using only physiological cues like convergence and binocular parallax.They were also tested in a usual visual field where they could judge the distance to the target using both physiological cues and experienteal ones.Before operation,these monkeys caught the raisin within reach quickly and accurately both in a uniform visual field and a usual visual field.They did not project their hands to the raisin beyond reach.After operation, the nomkeys with the inferior parietal lesion showed misreaching to the raisin within reach and projected their hands to the raisin beyond reach more frequently.These behavioral changes were observed both in a uniform visual field and a usual visual field.On the other hand,the monkeys with the frontal prearcuate lesion showed slight difficulties to catch the raisin within reach in a uniform visual field.They caught the raisin within reach accurately in a usual visual field.They did not project their hands to the raisin beyaond reach both in a uniform visual field and a usual visual field. Hand projection to the raisin beyond reach observed in the monkeys with the inferior parietal lesion suggests that these monkeys underestimated the distance to the raisin.In other words,it shows that the monkey with the inferior parietal lesion has difficulty in depth perception.