Shevelev I A, Sharaev G A, Lazareva N A, Novikova R V, Tikhomirov A S
Department of Sensory Systems, Russian Academy of Sciences, Moscow.
Neuroscience. 1993 Oct;56(4):865-76. doi: 10.1016/0306-4522(93)90133-z.
Dynamics of orientation tuning was studied by a flashing light bar in 233 single units of cat primary visual cortex. Orientation tuning was plotted by the criterion of spike number in successive fragments of responses with a step of 10 or 20 ms. Preferred orientation and the width of orientation tuning were measured for each of such curves. It was found that successive dynamic change of preferred orientation during response was typical for 63% of units under study, while such change of orientation tuning width was typical for 93%. Neurons with or without shift in preferred orientation differed in their response characteristics: latency and duration of discharge, its frequency and response rise time, as well as quality of orientation tuning. Possible functional significance of two groups of cortical units, "scanners" (with systematic preferred orientation shift) and "timers" (without it), is discussed in accordance with the idea of spatiotemporal orientation coding in the primary visual cortex.
通过在猫的初级视觉皮层的233个单个神经元中使用闪烁的光条来研究方向调谐的动力学。根据以10或20毫秒为步长的连续反应片段峰值数量标准绘制方向调谐曲线。测量每条这样的曲线的偏好方向和方向调谐宽度。结果发现，所研究的63% 单元在反应过程中偏好方向的连续动态变化是典型的，而93% 的单元方向调谐宽度的这种变化是典型的。偏好方向有或没有偏移的神经元在其反应特征上有所不同：放电潜伏期和持续时间、频率和反应上升时间，以及方向调谐质量。根据初级视觉皮层中时空方向编码的观点，讨论了两组皮层单元 “扫描器”（具有系统的偏好方向偏移）和 “定时器”（没有偏移）可能的功能意义。
