投稿日:2007/08/18投稿者:小島千昭
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(金) 14:00--15:30

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)

講演者:Bijoy K. Ghosh 教授 
       (Texas Tech University) 

講演題目: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@ipc.i.u-tokyo.ac.jp)
         小島千昭   (chiaki_kojima@ipc.i.u-tokyo.ac.jp)