Murphy M J, Goldblatt D
Arch Neurol. 1977 Mar;34(3):191-5. doi: 10.1001/archneur.1977.00500150077016.
Saccadic and smooth eye movements are controlled by separate mechanisms within the nervous system. We describe a patient with familial ataxia, considered to be a form of olivopontocerebellar degeneration, who is incapable of generating reflex or voluntary saccades. She can, however, move her eyes smoothly to the normal limits of lateral gaze, even when her head is prevented from moving. Latency before onset of movement is prolonged, and the velocity of movement is abnormally slow. We postulate that the degenerative process may have affected selectively those cells of the ventral paramedian pontine tegmentum responsible for the generation of saccades; and the the prolonged latency from presentation of a visual stimulus to the onset of movement is related to an inability to generate burst discharges needed to overcome the viscoelastic properties of the orbital tissues.
眼球的快速扫视运动和平稳跟踪运动由神经系统内不同的机制控制。我们描述了一位患有家族性共济失调的患者，该病被认为是橄榄桥脑小脑变性的一种形式，该患者无法产生反射性或自主性快速扫视运动。然而，即使头部不能移动，她也能够将眼睛平稳地移动到外展注视的正常极限位置。运动开始前的潜伏期延长，且运动速度异常缓慢。我们推测，变性过程可能选择性地影响了脑桥被盖腹侧正中负责产生快速扫视运动的那些细胞；并且从视觉刺激呈现到运动开始的潜伏期延长与无法产生克服眼眶组织粘弹性所需的爆发性放电有关。
