Image Parsing Mechanisms of the Visual Cortex
Image Parsing Mechanisms of the Visual Cortex
复制标题
视觉皮层的图像解析机制
DOI：
--
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发表时间：
2002
期刊：
影响因子：
--
通讯作者：
Krieger
中科院分区：
文献类型：
--
作者：
J. Werner;R. Heydt;Krieger
在本章中，我将讨论通常被标记为“中级视觉”的视觉过程。作为一个有用的框架，我们将视觉视为一系列过程，每个过程都是从一种表示到另一种表示的映射。理解视觉意味着分析信息在每个阶段的表示方式以及信息在阶段之间的转换方式（Marr，1982）。很明显，第一阶段，即感光器水平，是图像表示。这是一个二维颜色值数组，类似于数字计算机的位图格式。视网膜过程将这种表示转换成适合通过视神经传输到中枢大脑结构的格式。然后初级视觉皮层发生根本性的转变。在区域 V1 的输出处，我们发现编码为“特征图”的视觉信息，即局部特征的表示。视网膜位置的二维被编码在皮层神经元感受野的位置中，但每个神经元现在代表的不是一个像素，而是图像的一小块，并且在三个颜色维度中添加了几个新维度，例如方向、空间频率、运动方向和双眼视差。虽然 V1 的局部特征表示已被详细了解，但我们仍然对纹状外区域的处理本质没有很好的理解。乍一看，V2 区神经元的视觉特性与其 V1 区输入神经元的视觉特性非常相似，只是 V2 神经元具有更大的感受野（Zeki，1978；Burkhalter 和 Van Essen，1986）。 V4 区的许多神经元再次具有 V1 和 V2 中已经存在的属性，例如颜色、方向和空间频率的选择性（Zeki，1978；Desimone 等人，1985；Schein 和 Desimone，1990）。纹外区域的一些神经元对日益复杂的特征表现出选择性（参见康纳，本卷第 xx 章）。在这里，我将回顾证据，证明纹外区域提供了一个新的处理阶段，可以将其描述为“图像解析”。该阶段表现为 V1 的局部特征表示与注意选择和对象识别过程之间的中介。视觉系统从每时每刻通过视神经流入的大量信息中选择一小部分，并且通常准确地选择与……相关的信息。
In this chapter I will discuss visual processes that are often labeled as " intermediate level vision ". As a useful framework we consider vision as a sequence of processes each of which is a mapping from one representation to another. Understanding vision then means analyzing how information is represented at each stage and how it is transformed between stages (Marr, 1982). It is clear that the first stage, the level of the photoreceptors, is an image representation. This is a 2-dimensional array of color values, resembling the bitmap format of digital computers. Retinal processes transform this representation into a format that is suitable for transmission through the optic nerve to central brain structures. A radical transformation then takes place in the primary visual cortex. At the output of area V1 we find visual information encoded as a " feature map " , a representation of local features. The two dimensions of retinal position are encoded in the locations of the receptive fields of cortical neurons, but each neuron now represents not a pixel, but a small patch of the image, and several new dimensions are added to the three color dimensions, such as orientation, spatial frequency, direction of motion, and binocular disparity. While the local feature representation of V1 is known in detail, we still do not have a good understanding of the nature of processing in the extra-striate areas. At first glance, the visual properties of the neurons in area V2 are rather similar to those of their input neurons of V1, except that V2 neurons have larger receptive fields (Zeki, 1978; Burkhalter and Van Essen, 1986). Many neurons of area V4 again have properties that can be found already in V1 and V2, such as selectivity for color, orientation, and spatial frequency (Zeki, 1978; Desimone et al., 1985; Schein and Desimone, 1990). Some neurons in the extrastriate areas show selectivity for increasingly complex features (see Connor, Chapter xx, this volume). Here, I will review evidence that the extrastriate areas provide a new stage of processing that may be described as " image parsing ". This stage appears as a mediator between the local feature representation of V1 and the processes of attentional selection and object recognition. From the enormous amount of information that streams in through the optic nerves at each moment the visual system selects a small fraction, and in general precisely what is relevant for …
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影响因子：
3.7
作者：
Felleman, Daniel J.;Van Essen, David C.
通讯作者：
Van Essen, David C.
影响因子：
3.7
作者：
Ramsden, BM;Hung, CP;Roe, AW
通讯作者：
Roe, AW
DOI：
10.1152/jn.1996.75.2.523
发表时间：
1996
期刊：
Journal of neurophysiology.
影响因子：
--
作者：
Westheimer,G;Li,W
通讯作者：
Li,W
影响因子：
56.9
作者：
LOGOTHETIS, NK;SCHALL, JD
通讯作者：
SCHALL, JD