東京大学工学部計数工学科　システム情報談話会

日時：2007年9月14日（火）　11:00--12:30

場所：東京大学工学部6号館　3階セミナー室A （本郷キャンパス）　　　

(アクセス) http://www.i.u-tokyo.ac.jp/map/index.shtml#hongo

講師：Bijoy K. Ghosh 教授
         (Texas Tech University)

題目：Control and Signal Processing in Animal Vision

概要： In this problem we study how the visual circuit of an animal is able to track a mobile target in its visual space. The first problem we discuss is the gaze control problem wherein the rotational dynamics of the eye is introduced. The control objective is to ensure that the gaze of the eye is always directed towards a mobile target. Rotational motion of an eye satisfies a constraint known as the ‘Listing’s Law’. An optimal control is derived that ensures the eye movement between an initial and final gaze while satisfying the Listing’s constraint. The second problem we discuss is how a population of neurons encodes images on the retina. Specifically we show that visual images produce a wave of visual activity in a portion of the visual circuit known as the ‘visual cortex.’ A dynamic model of the visual cortex with four distinct classes of neurons is introduced that produces a cortical wave. Statistical analysis of the wave shows that they encode position and velocity cues from the visual space. An animal can use the cortical activity patterns to decode these features from the visual space.

連絡先: 原 辰次 (shinji_hara (at) ipc.i.u-tokyo.ac.jp)
            小島千昭 (chiaki_kojima (at) ipc.i.u-tokyo.ac.jp)