Human Ventral Occipitotemporal Cortex

描述（由申请人提供）：腹侧枕颞（VO）皮层区域的损伤可导致微妙的感知问题，如色盲和面容失认症。因此，人们普遍认为，VO皮层的神经回路从初级视皮层提供的相对低水平的输入计算中级视觉特性。然而，视网膜组织和颜色之间的关系，并没有仔细测量人类VO皮层的面部反应。例如，尚未确定颜色和物体信息的处理是否发生在视网膜皮层或没有视网膜组织的区域中，也许使用纯粹的反射不变计算。拟议的实验将确定腹侧VO皮层的功能组织使用功能磁共振成像。第一组实验（目标1）将绘制VO皮层的视野反应。这些视网膜定位图将与目标2和目标3中确定的颜色选择性和面部/物体选择性区域进行比较。这些实验应该解决的问题，视网膜组织的区域，选择性地响应颜色和面孔/对象。这些实验也将阐明VO皮层中中央凹、颜色和物体反应之间的空间关系。了解这个皮层区域的正常功能组织有两个目的。首先，它将增强我们对大脑如何处理有关物体属性的中级视觉信息的知识。其次，它可以帮助我们了解的变化，在严重程度和恢复程度的视觉缺陷从VO皮层病变。

DESCRIPTION (provided by applicant): Damage to regions of the ventral occipitotemporal (VO) cortex can result in subtle perceptual problems, such as achromatopsia and prosopagnosia. Consequently, it is widely believed that the neural circuitry in VO cortex computes mid-level visual properties from the relatively low level input provided by primary visual cortex. However, the relationship among retinotopic organization and color and face responses in human VO cortex has not been carefully measured. For example, it has not been established whether the processing of color and object information occurs within retinotopic cortex or in areas without retinotopic organization, perhaps using a purely translation-invariant computation. The proposed experiments will determine the functional organization of the ventral VO cortex using functional magnetic resonance imaging. The first set of experiments (Aim 1) will map the visual field responses of VO cortex. These retinotopic maps will be compared with the color-selective and face/object selective regions determined in Aim 2 and Aim 3. These experiments should resolve the question of retinotopic organization in regions that respond selectively to color and faces/objects. These experiments will also clarify the spatial relationship among foveal, color, and object responses in VO cortex. Understanding the normal functional organization of this cortical region will serve two purposes. First, it will enhance our knowledge of how the brain processes mid-level visual information about object properties. Second, it may help us understand the variability in the severity and in the degree of recovery of visual deficits from VO cortical lesions.