Diogo Antonia Cinira, Soares Juliana G M, Albright Thomas D, Gattass Ricardo
Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Brazil.
An Acad Bras Cienc. 2002 Sep;74(3):463-76. doi: 10.1590/s0001-37652002000300009.
We studied the spatial organization of direction of motion in visual area MT of the Cebus apella monkey. We used arrays of 6 (700 micro m apart) parallel electrodes in penetrations tangential to the cortical layers to record multi-unit responses to moving bars, at 200 micro m steps. We determined the direction selectivity at each recording site. The data from single penetrations showed cyclic and gradual changes in the direction selectivity of clusters of cells, intermixed with abrupt 180 degrees discontinuities along the electrode track. In order to obtain maps of direction of motion selectivity, we examined the spatial distribution of direction of motion in MT and we applied a method to determine the location of the centers of radial arrangements of direction selectivity. This tangential organization is characterized by slow continuous changes in direction of motion, interrupted by discontinuities. The changes in direction selectivity are organized radially in a pinwheel fashion and in slabs of linear variation. The pinwheel arrangements have 800-1400 micro m in diameter. The size of the radial arrangement is comparable to the point image size in area MT at each eccentricity.
我们研究了僧帽猴视皮层MT区中运动方向的空间组织。我们使用6个（彼此相距700微米）平行电极组成的阵列，在与皮层各层相切的穿透路径上，以200微米的步长记录对移动光条的多单元反应。我们确定了每个记录位点的方向选择性。来自单个穿透路径的数据显示，细胞簇的方向选择性呈周期性和逐渐变化，同时沿电极轨迹存在180度的突然不连续。为了获得运动方向选择性图谱，我们研究了MT区中运动方向的空间分布，并应用一种方法来确定方向选择性呈放射状排列的中心位置。这种切向组织的特征是运动方向缓慢连续变化，被不连续打断。方向选择性的变化以风车状和线性变化的平板形式呈放射状组织。风车状排列的直径为800 - 1400微米。放射状排列的大小与MT区中每个偏心位置的点图像大小相当。
