Schlag J, Schlag-Rey M, Peck C K, Joseph J P
Exp Brain Res. 1980;40(2):l70-84. doi: 10.1007/BF00237535.
Visual receptive field properties of neurons in the region of the thalamic internal medullary lamina were studied in alert cats while they fixated in various directions. In slightly more than 50% of the cells, the responsiveness of the cells was found to depend on the location of the stimulus with respect to the head-body axis (stimulus absolute position). A cell could ignore a stimulus outside its absolute field even if it was well placed within its receptive field. Three types of neurons were distinguished. Neurons with small central receptive fields were tonically activated when the animal fixated the stimulus in one half of the screen (usually contralateral). The firing rate of these cells was related to the stimulus absolute position measured along a preferred axis. Similarly, neurons with large receptive fields fired as a function of stimulus absolute position but stimulus fixation was not required. Neurons with eccentric fields responded to stimuli located in a target area defined in head-body coordinates. Such cells gave presaccadic bursts with eye movements terminating in the target area. The conclusion proposed is that neurons exist which code visual spatial information in a non-retinal frame of reference. This coding takes place at the time of stimulus presentation. Its role may be seen in the initiation of visually guided movements.
在警觉的猫注视不同方向时，对丘脑内髓板区域神经元的视觉感受野特性进行了研究。在略多于50%的细胞中，发现细胞的反应性取决于刺激相对于头体轴的位置（刺激绝对位置）。即使刺激位于其感受野内合适位置，细胞也可能忽略其绝对视野外的刺激。区分出了三种类型的神经元。当动物注视屏幕一半（通常是对侧）的刺激时，具有小中央感受野的神经元会持续被激活。这些细胞的放电频率与沿首选轴测量的刺激绝对位置有关。同样，具有大感受野的神经元根据刺激绝对位置放电，但不需要刺激固定。具有偏心视野的神经元对位于以头体坐标定义的目标区域内的刺激做出反应。这类细胞在眼动终止于目标区域时会产生眼跳前爆发。所提出的结论是，存在以非视网膜参照系编码视觉空间信息的神经元。这种编码在刺激呈现时发生。其作用可能体现在视觉引导运动的启动中。
