2013 Fiscal Year Final Research Report

Motion perception in depth induced by cast shadow.

Research Project

Project/Area Number	23500382
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Research Field	Neuroscience in general
Research Institution	Tokyo Medical and Dental University
Principal Investigator	NARUMI Katsuyama 東京医科歯科大学, 医歯(薬)学総合研究科, 助教 (00291906)
Project Period (FY)	2011 – 2013
Keywords	奥行き知覚 / キャストシャドウ / 機能的MRI / 背側経路 / サル
Research Abstract	Cast shadow is a salient monocular depth cue. In the present study, we investigated which cortical areas are involved in depth perception by moving cast shadow with functional MRI technique. A movie of a motion illusion was presented to participants. They were required to discriminate the perceived motion in depth (approaching and receding) of a square induced by its moving shadow cast on the background. The fMRI result showed activation in the bilateral hMT, V3A, and the right posterior intraparietal sulcus. Activation in these areas was also observed during discrimination of approaching and receding of a square represented by binocular disparity. These results suggest that cortical areas in the dorsal pathway may be involved in the integration of binocular and monocular depth cues and motion perception in depth induced by cast shadow. We have also revealed that macaque monkeys have depth perception by cast shadow by behavioral study.