Reid R C, Victor J D, Shapley R M
Rockefeller University, Laboratory of Biophysics, New York, New York, USA.
Vis Neurosci. 1997 Nov-Dec;14(6):1015-27. doi: 10.1017/s0952523800011743.
We have used Sutter's (1987) spatiotemporal m-sequence method to map the receptive fields of neurons in the visual system of the cat. The stimulus consisted of a grid of 16 x 16 square regions, each of which was modulated in time by a pseudorandom binary signal, known as an m-sequence. Several strategies for displaying the m-sequence stimulus are presented. The results of the method are illustrated with two examples. For both geniculate neurons and cortical simple cells, the measurement of first-order response properties with the m-sequence method provided a detailed characterization of classical receptive-field structures. First, we measured a spatiotemporal map of both the center and surround of a Y-cell in the lateral geniculate nucleus (LGN). The time courses of the center responses was biphasic: OFF at short latencies, ON at longer latencies. The surround was also biphasic--ON then OFF--but somewhat slower. Second, we mapped the response properties of an area 17 directional simple cell. The response dynamics of the ON and OFF subregions varied considerably; the time to peak ranged over more than a factor of two. This spatiotemporal inseparability is related to the cell's directional selectivity (Reid et al., 1987, 1991; McLean & Palmer, 1989; McLean et al., 1994). The detail with which the time course of response can be measured at many different positions is one of the strengths of the m-sequence method.
我们采用了萨特（1987年）的时空m序列方法来绘制猫视觉系统中神经元的感受野。刺激由一个16×16的正方形区域网格组成，每个区域由一个伪随机二进制信号（即m序列）进行时间调制。文中介绍了几种显示m序列刺激的策略。该方法的结果通过两个例子进行说明。对于膝状神经元和皮层简单细胞，用m序列方法测量一阶反应特性能够详细表征经典感受野结构。首先，我们测量了外侧膝状核（LGN）中一个Y细胞的中心和周边的时空图。中心反应的时间进程是双相的：短潜伏期为OFF，长潜伏期为ON。周边也是双相的——先ON后OFF——但速度稍慢。其次，我们绘制了17区方向简单细胞的反应特性图。ON和OFF子区域的反应动态变化很大；峰值时间范围超过两倍。这种时空不可分离性与细胞的方向选择性有关（里德等人，1987年、1991年；麦克林和帕尔默，1989年；麦克林等人，1994年）。能够在许多不同位置测量反应时间进程的详细程度是m序列方法的优势之一。
