Heinen Klaartje, Jolij Jacob, Lamme Victor A F
Anatomy Department, Wellcome Department of Imaging Neuroscience, University College London, London WC1E6BT, UK.
Neuroreport. 2005 Sep 8;16(13):1483-7. doi: 10.1097/01.wnr.0000175611.26485.c8.
Discriminating objects from their surroundings by the visual system is known as figure-ground segregation. This process entails two different subprocesses: boundary detection and subsequent surface segregation or 'filling in'. In this study, we used transcranial magnetic stimulation to test the hypothesis that temporally distinct processes in V1 and related early visual areas such as V2 or V3 are causally related to the process of figure-ground segregation. Our results indicate that correct discrimination between two visual stimuli, which relies on figure-ground segregation, requires two separate periods of information processing in the early visual cortex: one around 130-160 ms and the other around 250-280 ms.
视觉系统将物体与其周围环境区分开来的过程被称为图形-背景分离。这个过程需要两个不同的子过程：边界检测以及随后的表面分离或“填充”。在本研究中，我们使用经颅磁刺激来检验这样一个假设，即V1以及诸如V2或V3等相关早期视觉区域中在时间上不同的过程与图形-背景分离过程存在因果关系。我们的结果表明，依赖于图形-背景分离的两种视觉刺激之间的正确辨别需要早期视觉皮层中两个独立的信息处理阶段：一个在130 - 160毫秒左右，另一个在250 - 280毫秒左右。
