Smooth pursuitlike eye movements evoked by microstimulation in macaque nucleus reticularis tegmenti pontis.
Smooth pursuitlike eye movements evoked by microstimulation in macaque nucleus reticularis tegmenti pontis.
复制标题
猕猴脑桥网状核的微刺激引起平滑的追踪式眼球运动。
DOI：
10.1152/jn.1996.76.5.3313
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
Yee,RD
中科院分区：
文献类型：
--
作者：
Yamada,T;Suzuki,DA;Yee,RD
1.低电流微刺激传递到警觉猕猴的脑桥被盖网状核（rNRTP）的吻侧部分，诱发平滑的追踪样眼球运动。通过观察与周期性smoothpursuit眼球运动相关的单细胞放电率的调制来选择微刺激位点。电流强度范围为10至120微安，通常< 40微安。微刺激是在黑暗中没有固定，固定目标熄灭后100毫秒，或在保持固定的固定或移动的目标。在开环条件下研究了诱发的眼球运动，目标图像稳定在视网膜上。2.在没有目标的情况下诱发的眼球运动迅速加速到恒定的速度，该速度在微刺激的持续时间内保持不变。诱发眼速度范围为3.7至23度/秒，平均11度/秒。诱发眼速度似乎与初始眼位置线性相关，对初始眼位置的敏感度平均为0.23 deg.s-1. deg-1。虽然引起了一些水平和倾斜的平滑眼球运动，但微刺激导致89%的部位的眼球向上运动。3.诱发眼速被发现是依赖于微刺激脉冲频率和电流强度。在一定范围内，诱发眼速度随着刺激频率或电流强度的增加而增加。对于< 300-400 Hz的刺激频率，仅诱发平滑的追踪样眼球运动。在较高的刺激频率，伴随扫视一致地引起。4.视网膜图像运动的反馈与诱发的眼球运动相互作用，以降低眼球速度，如果视觉运动是在相反的方向作为诱发，追求样眼球运动。5.这些结果表明，rNRTP作为控制平滑追踪眼球运动的神经元基质的一部分。NRTP似乎在功能上分为吻侧，追求相关的部分和尾侧，扫视相关的区域。rNRTP是皮质桥脑小脑回路的一个组成部分，推测其涉及额叶眼野的追踪区域，并平行于中间和内侧上级颞大脑皮质/背外侧脑桥核（MT/MST-DLPN-小脑）通路，已知该通路也涉及调节平滑追踪眼球运动。
1. Smooth pursuitlike eye movements were evoked with low current microstimulation delivered to rostral portions of the nucleus reticularis tegmenti pontis (rNRTP) in alert macaques. Microstimulation sites were selected by the observation of modulations in single-cell firing rates that were correlated with periodic smoothpursuit eye movements. Current intensities ranged from 10 to 120 microA and were routinely < 40 microA. Microstimulation was delivered either in the dark with no fixation, 100 ms after a fixation target was extinguished, or during maintained fixation of a stationary or moving target. Evoked eye movements also were studied under open-loop conditions with the target image stabilized on the retina. 2. Eye movements evoked in the absence of a target rapidly accelerated to a constant velocity that was maintained for the duration of the microstimulation. Evoked eye speeds ranged from 3.7 to 23 deg/s and averaged 11 deg/s. Evoked eye speed appeared to be linearly related to initial eye position with a sensitivity to initial eye position that averaged 0.23 deg.s-1.deg-1. While some horizontal and oblique smooth eye movements were elicited, microstimulation resulted in upward eye movements in 89% of the sites. 3. Evoked eye speed was found to be dependent on microstimulation pulse frequency and current intensity. Within limits, evoked eye speed increased with increases in stimulation frequency or current intensity. For stimulation frequencies < 300–400 Hz, only smooth pursuit-like eye movements were evoked. At higher stimulation frequencies, accompanying saccades consistently were elicited. 4. Feedback of retinal image motion interacted with the evoked eye movements to decrease eye speed if the visual motion was in the opposite direction as the evoked, pursuit-like eye movements. 5. The results implicate rNRTP as part of the neuronal substrate that controls smooth-pursuit eye movements. NRTP appears to be divided functionally into a rostral, pursuit-related portion and a caudal, saccade-related area. rNRTP is a component of a corticopontocerebellar circuit that presumably involves the pursuit area of the frontal eye field and that parallels the middle and medial superior temporal cerebral cortical/dorsalateral pontine nucleus (MT/MST-DLPN-cerebellum) pathway known to be involved also with regulating smooth-pursuit eye movements.