Study on improvement of eye-head coordination pattern by means of target tracking in hemianoptic agnosia.

本文记录了26名正常人和5名偏瘫患者在追踪平稳移动的视觉目标时的眼动和头部运动。对照组的眼动和头部运动表现为眼球运动和头部运动的协调模式，这种模式已在眼跳运动中发现：眼球运动先于头部运动，速度高于头部。因此，眼睛到头轴的角位移大于头到体轴的角位移。然而，后来，头部旋转的速度逐渐加快，眼睛的旋转速度也变慢，以保持凝视点在目标上。最后，眼动被反转(补偿性眼动)，与手部追踪相比，头部的角位移比没有手部追踪时要小。人们认为头部旋转被抑制了。这项实验的结果可以通过假设前庭输入必须被控制以精确地注视来很好地解释。同义偏盲的眼睛和头部运动描述如下。控制组的眼睛和头部运动显示出类似的模式。2.眼球和头部旋转的幅度与对照组不同。当同义性偏盲追逐移动目标到视野丧失一侧时，眼球旋转减速，相应地，头部加速以保持凝视位置。3.眼动障碍发生率高于对照组。4.手部追踪时，5个对照组中有1个呈现相似的模式。其余4个没有变化。5.眼球运动变得流畅、准确，但脱靶次数较多。6.从这些结果来看，同义偏盲已经学会了扩展动态视野。用手追踪可能会刺激神经系统，从而产生眼头协调程序。因此，康复训练计划最好在这些过程中制定。这些结果发表在科学期刊(1)和国会(2)上。

Eye and head movements during tracking of smoothly moving visual target were recorded in 26 controls and 5 partially blinded humans with hemiplegia.Eye and head movements in controls showed coordinated pattern which had been found in saccadic movement.: The eye movement started before head moved and the velocity was higher than head. Therefore,the angular displacement of eye to head axis became larger than head to body axis. However, later, the head rotation speeded up gradually and the eye rotation speeded down for keeping the gaze point on the target. Finallly, eye movement was reversed (compensatory eye movement).When compared with tracking with hand pursuit, angular displacement of head was smaller than without hand pursuit. It was thought that head rotation was suppressed. The result of this experiment can be explained best by postulating that vestibular input must be controlled for a precise gaze.Eye and head movements in homonymous hemianopsias are described below.1. The eye and head movements showed similar pattern in controls. 2. Amplitude of the eye and head rotation was different from controls. When homonymous hemianopsias pursued a moving target to the side of visual field loss, the eye rotation decelerated and correspondingly, the head accelerated in order to maintain the gaze position. 3. And the eye movement was disturbed more frequently than in controls. 4. When tracking with hand pursuit, one of 5 showed simillar pattern in controlls. The remaining 4 did not change. 5. While the eye movement became smooth and accurate, but missed the target more frequently. 6. From these results, the homonymous hemianopsias already have learned to expand the dynamic visual field. Tracking with hand pursuit may stimulate the nervous system making the eye-head coordintion program. Therefore, training program for rehabilitation had better make on these process. These results were reported in scientific journal(1) and congress(2).