Blink-perturbed saccades in monkey. II. Superior colliculus activity
Blink-perturbed saccades in monkey. II. Superior colliculus activity
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DOI：
10.1152/jn.2000.83.6.3430
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发表时间：
2000-06-01
影响因子：
2.5
通讯作者：
Van Opstal, AJ
中科院分区：
文献类型：
--
作者：
Goossens, HHLM;Van Opstal, AJ
三叉神经反射眨眼诱发附近的一个扫视的发作引起深刻的时空扰动的扫视，通常在飞行中补偿。本文研究了反射性眨眼对猴上级丘（SC）中层和深层眼跳相关爆发神经元（SRBN）放电特性的影响。二十九SRBN，记录在三只猴子，进行了测试，在眨眼扰动范例。我们报告说，空气喷刺激，用于引起眨眼，导致在短潜伏期（类似于10毫秒）的短暂抑制扫视相关SRBN活动。在这种抑制后不久（10-30 ms内），所有神经元恢复其活动，然后继续其爆发放电，直到受干扰的扫视在熄灭的目标附近结束。无论补偿运动是否进入细胞的运动场，都发现了这一点。在没有补偿发生的有限数量的试验中，神经元通常在眼球运动结束之前就停止了放电。对于25个SRBN，扫视相关活动的几个方面可以进一步量化。似乎1）高频爆发持续时间的增加与扰动运动持续时间的增加（两到三倍）密切相关。2)控制和扰动扫视的爆发中的尖峰数量非常相似。平均而言，尖峰的数量只增加了14%，而爆发中的平均放电率下降了52%。3)当爆发和后扫视活动都包括在尖峰计数控制和扰动的反应之间获得了相同数量的尖峰。4)在爆发的平均放电率的下降与扰动扫视的速度下降有很好的相关性。5)瞬时点火率和动态电机误差之间的单调关系，得到的控制响应，但不是扰动响应。6）短导联和长导联前放电的SRBN（也分别称为爆发神经元和建立神经元）的高频爆发表现出非常相似的特征。我们的研究结果表明，眨眼与眼跳前运动系统已经在SC的水平。数据还表明，神经机制，而不是被动的弹性恢复力内的oculabular植物，眨眼相关的扰动补偿的基础。我们建议，这些相互作用发生在下游的电机SC，后者可以编码所需的位移矢量的眼睛发送一个近似固定数量的尖峰脑干扫视爆发发生器。
Trigeminal reflex blinks evoked near the onset of a saccade cause profound spatial-temporal perturbations of the saccade that are typically compensated in mid-flight. This paper investigates the influence of reflex blinks on the discharge properties of saccade-related burst neurons (SRBNs) in intermediate and deep layers of the monkey superior colliculus (SC). Twenty-nine SRBNs, recorded in three monkeys, were tested in the blink-perturbation paradigm. We report that the air puff stimuli, used to elicit blinks, resulted in a short-latency (similar to 10 ms) transient suppression of saccade-related SRBN activity. Shortly after this suppression (within 10-30 ms), all neurons resumed their activity, and their burst discharge then continued until the perturbed saccade ended near the extinguished target. This was found regardless whether the compensatory movement was into the cell's movement field or not. In the limited number of trials where no compensation occurred, the neurons typically stopped firing well before the end of the eye movement. Several aspects of the saccade-related activity could be further quantified for 25 SRBNs. It appeared that 1) the increase in duration of the high-frequency burst was well correlated with the (two- to threefold) increase in duration of the perturbed movement. 2) The number of spikes in the burst for control and perturbed saccades was quite similar. On average, the number of spikes increased only 14%, whereas the mean firing rate in the burst decreased by 52%. 3) An identical number of spikes were obtained between control and perturbed responses when burst and postsaccadic activity were both included in the spike count. 4) The decrease of the mean firing rate in the burst was well correlated with the decrease in the velocity of perturbed saccades. 5) Monotonic relations between instantaneous firing rate and dynamic motor error were obtained for control responses but not for perturbed responses. And 6) the high-frequency burst of SRBNs with short-lead and long-lead presaccadic activity (also referred to as burst and buildup neurons, respectively) showed very similar features. Our findings show that blinking interacts with the saccade premotor system already at the level of the SC. The data also indicate that a neural mechanism, rather than passive elastic restoring forces within the oculomotor plant, underlies the compensation for blink-related perturbations. We propose that these interactions occur downstream from the motor SC and that the latter may encode the desired displacement vector of the eyes by sending an approximately fixed number of spikes to the brainstem saccadic burst generator.