Visual effects on vergence eye movements elicited by linear motion along the naso-occipital axis

强烈的眼球运动是由视觉刺激和鼻枕部(NO)的线性头部运动引起的。作为了解非直线运动时收敛眼动神经机制的第一步，我研究了视觉刺激对猴子前向直线运动眼动反应的影响。为此，我构建了一个新的实验系统，该系统由线性雪橇、视觉刺激器和眼部记录系统组成。我使用了警觉的日本猕猴(Macaca Fuscata)，这些猴子以前被训练成注视小目标。在录音过程中，这只猴子坐在椅子上，头被头架固定住。我用1千赫的电磁搜索线圈系统用双筒望远镜测量了眼睛的水平和垂直位置。猴子座椅安装在直线雪橇上，沿着无轴方向产生0.1-0.5g的恒定线性加速度。将随机点图案(=Rd，69×69^o)大视场和/或红色中心注视靶(=FT，0.3^o)反投影到距猴子35 cm的屏幕上。结果表明，前向直线运动引起的四种发散反应如下：a.对潜伏期为4-6MSB的前庭刺激的发散反应。对前庭刺激的会聚反应潜伏期约为10msc。对RD大视场视觉场景的会聚响应，延迟约为45msd。潜伏期在70msRd左右的FT的会聚反应(=c)和FT(=d)的会聚反应增加了对前庭刺激的会聚反应(=b)。RD(=c)的作用强于FT(=d)。这些数据可能表明，对RD(=c)的会聚反应与对FT(=d)的会聚反应的神经机制不同。超短潜伏期的发散反应(=a)是我们没有预料到的眼睛反应。它们应该是未知的会聚眼球反应，接下来我将阐明它们的神经机制和功能。

Vergence eye movements are elicited by visual stimuli and also naso-occipital (NO) linear head motion. As the first step in understanding the neural mechanisms of vergence eye movements during NO linear motion, I studied the effects of visual stimulus on the oculomotor response to forward linear motion in monkeys.For this purpose, I constructed the new experiment system using a linear sled, a visual stimulator and an eye recording system. I used alert Japanese monkeys (Macaca fuscata) previously trained to fixate small targets. During recording sessions, the monkey was seated in a chair with its head secured by a head holder. I measured the horizontal and vertical eye positions binocularly using an electromagnetic search-coil system at 1 kHz. The monkey chair was mounted on a linear sled riding, which generated constant linear accelerations of 0.1 - 0.5 g along the NO-axis. A random-dot pattern (= RD, 69^ox69^o) large-field visual scene and/or a red center fixation target (= FT, 0.3^o) were/was back-projected onto a screen 35 cm away from the monkey. The results reveal that the four kinds vergence responses were elicited by forward linear motion as follows ;a. Divergence responses to vestibular stimulus with latencies of 4 - 6 msb. Convergence responses to vestibular stimulus with latencies of around 10 msc. Convergence responses to RD large-field visual scene with latencies of around 45 msd. Convergence responses to FT with latencies of around 70 msRD (= c) and FT (= d) increased convergence responses to vestibular stimulus (= b). The effects of RD (= c) were stronger than those of FT (= d). These data may show that the neural mechanisms of convergence responses to RD (= c) were not the same as those of convergence responses to FT (= d).Divergence responses with ultra short latencies (= a) were the eye responses we didn't expect. They should be the unknown vergence eye responses and next I will clarify their neural mechanisms and functions.