Neural Basis of Shape from Texture

根据纹理确定形状的神经基础

• 批准号: 6988331
• 负责人: Qasim Zaidi
• 金额: $ 33万
• 依托单位: STATE COLLEGE OF OPTOMETRY
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-03-01 至 2010-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6988331
• 关键词: behavioral /social science research tag; clinical research; cues; form /pattern perception; human subject; mathematical model; model design /development; neural information processing; neurons; psychophysics; single cell analysis; vision tests; visual stimulus

DESCRIPTION (provided by applicant): The aim of this project is to understand the three-dimensional shape perception of patterned surfaces. Extra-striate cortex includes many neurons that are selective to 3-D surface orientation defined by texture cues, but there are no feasible models of neural connections that build such receptive fields. We have shown that to extract 3-D shape from texture, assumptions of texture homogeneity and estimates of texture gradients are not needed. Instead, surface curvature/orientation estimates are provided by orientation flows, and depth estimates by frequency flows. These flows predict both correct perceptions and misperceptions. Since V1 neurons are selective for orientation and frequency, we will build models that combine their outputs to extract orientation and frequency flows for identifying distinct shape features. Experiments will specify the temporal and spatial properties of the neural mechanisms. We will use new types of diagnostic stimuli, without cue conflict, to examine the manner in which motion and texture cues interact in 3-D perception, and whether motion contributes to the perception of intrinsic curvature or just to relative depth. We will analyze shading patterns on naturalistic textured objects in terms of orientation flows and frequency gradients. We will see how these aspects of shading interact in 3-D perception, with orientation and frequency information from textures. We will examine how texture and silhouette cues interact to explain some motion and shape illusions with real 3-D solids. We will test whether neural mechanisms for shape-from texture are hard-wired or can be altered by experience, by using haptic feedback to correct misperceptions from texture cues. This study will show how simple neural connections lead to complex 3-D percepts. These results will be useful both in understanding the causes of neurological deficits in shape perception, and in building artificial visual aids for patients with such deficits.

描述(申请人提供)：本项目的目的是了解有图案的表面的三维形状感知。纹外皮质包括许多神经元，它们对纹理线索定义的3-D表面方向具有选择性，但没有可行的神经连接模型来建立这样的感受野。我们已经证明，要从纹理中提取三维形状，不需要假设纹理的同质性和估计纹理的梯度。取而代之的是，表面曲率/取向估计由取向流提供，深度估计由频率流提供。这些流动预测了正确的认知和错误的认知。由于V1神经元对方向和频率具有选择性，我们将建立模型，将它们的输出结合起来提取方向和频率流，以识别不同的形状特征。实验将详细说明神经机制的时间和空间特性。我们将使用新类型的诊断刺激，在没有线索冲突的情况下，检查运动和纹理线索在3-D知觉中相互作用的方式，以及运动是否有助于感知固有曲率，还是仅仅有助于相对深度。我们将从方向流和频率梯度方面分析自然纹理对象上的阴影模式。我们将看到着色的这些方面如何在3D感知中与来自纹理的方向和频率信息相互作用。我们将研究纹理和轮廓线索如何相互作用，以解释真实3-D实体的一些运动和形状错觉。我们将通过使用触觉反馈来纠正对纹理线索的误解，来测试从纹理到形状的神经机制是固有的还是可以被经验改变的。这项研究将展示简单的神经连接如何导致复杂的3D感知。这些结果将有助于理解神经形状知觉缺陷的原因，并为有此类缺陷的患者制造人工视觉辅助设备。