Eye movements induced by pontine stimulation: interaction with visually triggered saccades.
Eye movements induced by pontine stimulation: interaction with visually triggered saccades.
复制标题
脑桥刺激引起的眼球运动：与视觉触发的眼跳的相互作用。
DOI：
10.1152/jn.1987.58.2.300
复制
发表时间：
1987
影响因子：
2.5
通讯作者：
Porter,JD
中科院分区：
文献类型：
--
作者：
Sparks,DL;Mays,LE;Porter,JD
1. 恒河猴被训练观察在黑暗的房间中出现的简短视觉目标。在一些试验中，在视觉目标消失后但在开始扫视之前，通过对桥脑旁正中网状结构的微刺激，将眼睛驱动到另一个眼眶位置。如果，如扫视系统的当前模型所建议的那样，将运动命令的副本用作眼睛位置的反馈信号，则无法补偿刺激引起的运动将表明刺激发生在超出眼睛位置信号来源点的部位。 2. 动物通过眼跳将视线引导至视觉目标的位置来补偿由大多数脑桥部位的刺激引起的眼睛位置的扰动。当刺激其他脑桥部位时，没有发生代偿性眼跳。 3. 脑桥刺激有时会过早地触发即将发生的视觉定向扫视。过早运动的方向和幅度取决于短暂呈现的视觉目标的位置。过早运动的幅度也是刺激序列和即将发生的眼跳之间的间隔的函数。这些数据表明水平和垂直脉冲/步进发生器的输入信号在眼跳前间隔期间逐渐发展。扫视触发信号需要延迟，直到这些信号形成完成。 4. 讨论了这些发现对扫视系统模型的影响。罗宾逊的扫视系统局部反馈模型可以解释对脑桥刺激引起的眼睛位置变化的补偿，但不能轻易解释对其他部位刺激产生的眼睛位置扰动的未能补偿。罗宾逊模型的修改版本假设脉冲/阶跃发生器的输入信号是眼睛所需的位移，可以解释补偿和补偿失败，因为使用了两个单独的神经积分器。然而，这些模型忽略了运动学参数，即对眼外肌的命令必须指定眼睛在眼眶中的绝对位置，而不是与先前位置的相对运动。
1. Rhesus monkeys were trained to look to brief visual targets presented in an otherwise darkened room. On some trials, after the visual target was extinguished but before a saccade to it could be initiated, the eyes were driven to another orbital position by microstimulation of the paramedian pontine reticular formation. If, as current models of the saccadic system suggest, a copy of the motor command is used as a feedback signal of eye position, failure to compensate for stimulation-induced movements would indicate that stimulation occurred at a site beyond the point from which the eye position signal was derived. 2. Animals compensated for perturbations of eye position induced by stimulation of most pontine sites by making saccades that directed gaze to the position of the visual target. With stimulation at other pontine sites, compensatory saccades did not occur. 3. Pontine stimulation sometimes triggered, prematurely, impending visually directed saccades. The direction and amplitude of the premature movement depended upon the location of the briefly presented visual target. The amplitude of the premature movement was also a function of the interval between the stimulation train and the impending saccade. These data suggest that input signals for the horizontal and vertical pulse/step generators develop gradually during the presaccadic interval. Saccade trigger signals need to be delayed until the formation of these signals is completed. 4. The implications of these findings for models of the saccadic system are discussed. Robinson's local feedback model of the saccadic system can explain compensation for pontine stimulation-induced changes in eye position but cannot easily account for the failure to compensate for perturbations in eye position produced by stimulation at other sites. Modified versions of Robinson's model, which assume that the input signal to the pulse/step generator is the desired displacement of the eye, can account for both compensation and the failure to compensate since two separate neural integrators are employed. However, these models ignore kinematic arguments that commands to the extraocular muscles must specify the absolute position of the eye in the orbit rather than a relative movement from a previous position.
登录
查看更多内容
纠正性眼跳：依赖于视网膜再传入信号
影响因子：
1.8
作者：
C. Prablanc;M. Jeannerod
通讯作者：
M. Jeannerod
影响因子：
56.9
作者：
MAYS, LE;SPARKS, DL
通讯作者：
SPARKS, DL
影响因子：
--
作者：
E. Keller
通讯作者：
E. Keller
影响因子：
56.9
作者：
GUTHRIE, BL;PORTER, JD;SPARKS, DL
通讯作者：
SPARKS, DL
影响因子：
--
作者：
ZEE, DS;OPTICAN, LM;ENGEL, WK
通讯作者：
ENGEL, WK