第29回日本神経科学大会(京都)
平成18年7月19日〜21日
Program Number: OS3P-4-02 Presentation Time: Friday, July. 21, 14:15 - 14:30

Predicting the monkey's behavioral choice in a stereoacuity task from neuronal responses in area V4

Hiroshi Shiozaki, Seiji Tanabe, Ichiro Fujita

Lab. Cognitive Neurosci., Grad. Sch. Frontier Biosciences, Osaka Univ., Japan

Many neurons in visual area V4 of macaque monkeys are selective for binocular disparity. Most disparity-selective neurons in V4 are sensitive to small changes in disparity near zero, suggesting that they might contribute to stereoacuity. However, the role of these neurons in stereoscopic depth discrimination has not been directly addressed. We recorded single unit activity from V4 while a monkey was engaged in a fine stereoscopic depth discrimination or stereoacuity task. The monkey was trained to report by saccadic eye movement whether the center region of a random-dot stereogram was nearer or farther than its immediate surround. Trial-to-trial fluctuation of visual responses of V4 neurons was correlated with the monkey's subsequent behavioral choice. Given the cell's disparity preference, an ideal observer can predict the monkey's upcoming behavioral response from the visual response of V4 neurons. The results suggest that V4 neurons are involved in mediating stereoacuity.

Keywords: STEREOPSIS, VISUAL CORTEX, DECISION, ELECTROPHYSIOLOGY

Reserch Funds: Supported by a MEXT grant (17022025) and the Takeda Science Foundation.