The characteristics of preattentive process in vision and its neurophysiological basis.

前注意过程是一种在宽广的视野中快速、自动、无注意地处理信息的知觉模式。这一过程对于从输入信息中提取轮廓特征和快速形成高级认知的基本表征起着重要作用。通过对纹理知觉、视觉搜索、图形-背景知觉、视觉内插和复合模式知觉的实验，我们发现前注意过程具有以下共同特征。注意前加工的知觉反应快速、短暂，具有较高的时间频率偏好。它们的空间分辨率较低，但对具有相同特征的区域表现出较强的链接性。他们的亮度对比度敏感性非常好，但他们的颜色对比度敏感性很差。从这些发现，我们认为Livingstone和Hubel研究的Magno系统是前注意过程的神经生理学基础。大脑皮层神经元的感受野较大，反应较快。据报道，提取相同特征的神经元之间存在相互联系。Magno神经元具有较强的亮度对比度敏感性，但对颜色对比度的敏感性较差，现有的一些注意模型是基于WTA(Winner-Take-All)网络或基于振荡神经反应的同步。如果在MAGNO系统的活动范围内推广这些想法，就有可能抑制冗余信息，并有效地引导人们对目标识别的关键位置和分辨率的注意。

The preattentive process is a mode of perception in which the information is processed in a wide visual field, rapidly and automatically, without attention. This process plays an important role to pick up outline properties from the inputted information and to make quickly a basic representations for the formation of higher cognitions.We found the following common characteristics in preattentive process, from the experiments on texture perception, visual search, figure-ground perception, visual interpolation, and compound pattern perception. The perceptual responses in preattentive process are quick and transient, with higher temporal frequency preference. Their spatial resolution is low, but they show the strong linking property to process collectively the regions which have the same features. Their luminance contrast sensitivity is extremely good, but their color contrast sensitivity is poor.From these findings, we regard the magno system investigated by Livingstone & Hubel as a neurophysiological basis for the preattentive process. The receptive fields of the magno neurons are large and their responses are fast. The mutual connections are reported among the neurons which extract the same features. The magno neurons show strong luminace contrast sensitivity, but poor sensitivity to color contrast.Some of the current models of attention are proposed based on the WTA (Winner-Take-All) network or on the synchronization of oscillatory neural responses. If these ideas are extended in the context of the magno system's activity, it is suggest to be possible to inhibit redundant information and to guide attention effectively at the critical location and resolution for object recognition.