Luo Gang, Garaas Tyler, Pomplun Marc, Peli Eli
Schepens Eye Research Institute, Department of Ophthalmology, Harvard Medical School, Boston, USA.
J Vis. 2010 Oct 26;10(12):32. doi: 10.1167/10.12.32.
The view of two separate "what" and "where" visual systems is supported by compelling neurophysiological evidence. However, very little direct psychophysical evidence has been presented to suggest that the two functions can be separated in neurologically intact persons. Using a peri-saccadic perception paradigm in which bars of different lengths were flashed around saccade onset, we directly measured the perceived object size (a "what" attribute) and location (a "where" attribute). We found that the perceived object location shifted toward the saccade target to show strongly compressed localization, whereas the perceived object size was not compressed accordingly. This dissociation indicates that the perceived size is not determined by spatial localization of the object boundary, providing direct psychophysical evidence to support that "what" and "where" attributes of objects are indeed processed separately.
两个独立的“什么”和“哪里”视觉系统的观点得到了令人信服的神经生理学证据的支持。然而，几乎没有直接的心理物理学证据表明，在神经功能完好的个体中这两种功能可以分开。我们使用一种扫视周围感知范式，在扫视开始时闪烁不同长度的条，直接测量了感知到的物体大小（一种“什么”属性）和位置（一种“哪里”属性）。我们发现，感知到的物体位置向扫视目标移动，表现出强烈的压缩定位，而感知到的物体大小并没有相应地压缩。这种分离表明，感知到的大小不是由物体边界的空间定位决定的，提供了直接的心理物理学证据来支持物体的“什么”和“哪里”属性确实是分开处理的。
