NEURAL BASIS OF SHAPE FROM TEXTURE

描述：人类视觉I使用几种类型的单目线索，例如 阴影、纹理和运动，从2D图像中提取3D形状。这个项目 旨在提供从纹理线索的形状感知的独家描述 由真实的大脑皮层神经元执行的可行神经操作的术语。 拟议的工作建立在私人投资机构最近的结果表明，观察员 仅当图像包含以下内容时才能感知纹理表面的真实3D形状 沿曲面最大曲率的投影线的可见能量。本地 瓦楞纸板凹凸倾斜部分的光谱分析 曲面显示沿主曲面的投影线的等高线 曲率显示取向和频率调制的特征图案 系统地与表面的3D形状相关。私家侦探现在 寻求开发一种将V1神经元的输出与感知联系起来的模型 根据纹理线索确定形状。模型的前端将由数组 频率和方位选择神经元。频率和频率的模板模式 取向调制将由后面的细胞从集合中提取 等频和等向输出。计算模型将 需要对向量场的数学进行新的使用。神经细胞的特性 每一水平都将在清醒的猴子的单细胞录音中进行测试 在单独的协作中，从而在计算之间提供直接链接 和生理学。为了测试和扩展该模型，心理物理实验将 使用带有通常出现的方向干扰的图案，对比 定义的轮廓和自然产生的纹理。该项目将提供 将天然纹理分类为有效或无效的规则 在真实场景的计算机模拟中将非常有用的形状。

Description: Human vision I uses several types of monocular cues such as shading, texture and motion to extract 3D shape from 2D images. This project aims to provide an account of shape perception from texture cues exclusively in terms of feasible neural operations performed by realistic cortical neurons. The proposed work builds on the PIs' recent results showing that observers perceive the true 3D shape of a textured surface only when the image contains visible energy along projected lines of maximum curvature of the surface. Local spectral analyses of convex, concave and slanted portions of corrugated surfaces reveal that contours along projected lines of principal surface curvature show characteristic patterns of orientation and frequency modulations that are systematically related to the 3D shape of the surface. The Pis now seek to develop a model that relates the outputs of V1 neurons to perceived shape from texture cues. The front end of the model will consist of arrays of frequency and orientation-selective neurons. Template patterns of frequency and orientation modulations will be extracted by later cells from set of iso-frequency and iso-orientation outputs. The computational modeling will require new uses of the mathematics of vector fields. Properties of neurons at each level will be tested in single-cell recordings from awake behaving monkeys in a separate collaboration, thus providing a direct link between computation and physiology. To test and extend the model, psychophysical experiments will use patterns with generically occurring orientation distractors, contrast defined contours and naturally occurring textures. The project will provide rules for classifying natural textures as effective or ineffective at conveying shape which will be useful in computer simulations of realistic scenes.