LOCAL CIRCUITS & DIRECTION SELECTIVITY IN VISUAL CORTEX

描述：尽管该组织的详细情况越来越多， 视觉皮层的神经回路，我们还远未了解 将这些复杂的连接模式与 单个神经元的响应特性。 拟议的实验 专注于许多视觉皮层表现出的基本特性 神经元对运动方向的选择性。 方向选择性 神经元对适当定向的边缘的运动作出强烈的反应 在一个方向穿过它们的感受野，而且很弱，如果有的话， 向相反方向移动。 该补助金的目标是 确定模块化和地形布置的特殊性 皮质内连接的数量在塑造 皮层神经元的选择性反应。 这些实验是 可能是最近展示的一个系统的方向图， 在雪貂的第17区的偏好。 固有光成像 信号将用于可视化方向偏好图， 区域17，以及解剖追踪技术和体外 组织切片实验将用于评估空间排列 兴奋性和抑制性输入的神经元群体， 方向偏好 这些实验应该提供新的见解， 视觉皮层中局部回路的功能组织-- 这些信息对于理解视觉的神经基础至关重要， perception.

DESCRIPTION: Despite an increasingly detailed picture of the organization of neural circuits in visual cortex, we are still far from understanding the rules that relate these complex patterns of connections to the response properties of individual neurons. The proposed experiments focus on a fundamental property exhibited by many visual cortical neurons--selectivity for direction of motion. Direction selective neurons respond vigorously to movement of an appropriately oriented edge in one direction across their receptive field, and weakly, if at all, to movement in the opposite direction. The goal of this grant is to determine whether specificity in the modular and topographic arrangement of intracortical connections plays a role in shaping the direction selective responses of cortical neurons. These experiments are made possibly by the recent demonstration of a systematic map of direction preference in area 17 of the ferret. Optical imaging of intrinsic signals will be used to visualize the map of direction preference in area 17, and a combination of anatomical tracing techniques and in vitro tissue slice experiments will be used to assess the spatial arrangement of excitatory and inhibitory inputs to populations of neurons with known direction preference. These experiments should provide new insights into the functional organization of local circuits in visual cortex-- information that is crucial for understanding the neural basis of visual perception.