視覚—物体の質感認知

Visual Recognition of the Shitsukan, or Material Properties, of Objects

動物，花，木などの自然物，漆器，ガラス，コインなどの人工物，いずれも，その表面には固有の色，テクスチャ，光沢感などからなる視覚的質感が備わっている。近年の研究により，このような質感情報認知のための脳内機構が明らかになってきた。本稿では，物体の視覚的認識と深く関わる霊長類腹側視覚経路において，物体表面の色やテクスチャなどの質感情報がどのように処理され，神経活動に符号化されているのかについて紹介する。

Abstract

Natural objects, such as animals, flowers, and wood, as well as artificial objects, such as Japanese lacquerware, glass, and metal coins, have their own shape and surface appearances. Although object shapes play important roles in visual object recognition, the material properties or Shitsukan of objects are relevant for the recognition of visual objects. In this review, we introduce recent advances in the understanding of the neural basis of the cognition of Shitsukan. First, we introduce the results of single-neuron recording studies that examined neuronal activity in the inferior temporal cortex of macaque monkeys in response to the presentation of two-dimensional and three-dimensional shapes. Next, we introduce the studies of neuronal response property to the Shitsukan of objects, such as color, texture, glossiness, and the combinations of these features. Then, we discuss how the selective responses to Shitsukan are constructed by hierarchical processing in the ventral visual cortical pathway, which consists of V1, V2, and V4. Finally, we discuss the encoding of Shitsukan information in the inferior temporal cortex.