Optical imaging as a new technique probing into the brain

Abstract

Optical imaging of neural activities has been developed recently to investigate spatial and temporal aspects of brain functions. To transform neural activities into optical signals two probes are used: (1) voltage-sensitive dyes that transform membrane potential changes directly into optical signals; and (2) hemoglobin that changes its absorption when deoxygenation associated with neural activity occurs. The investigations using either probe, that is, signal propagation through visual cortical circuits and spatial representation of visual information in the inferotemporal area will be shortly reviewed.

脳機能の時空間的様相を研究する目的で、新しく神経活動の光学的イメージングを開発した。神経活動を光信号に変換するために次の2つのプローブを用いた。(1)膜電位変化を直接光信号に変える電圧感受性色素、および(2)神経活動に関連した脱酸素化が起こるとき、その吸収を変化するヘモグロビン。双方のプローブを用いた研究、すなわち、視覚皮質回路を通した信号伝送と下側頭部における視覚情報の空間的表現について簡単にレビューした。