Noise Correlations in Cortical Area MT and Their Potential Impact on Trial-by-Trial Variation in the Direction and Speed of Smooth-Pursuit Eye Movements
Noise Correlations in Cortical Area MT and Their Potential Impact on Trial-by-Trial Variation in the Direction and Speed of Smooth-Pursuit Eye Movements
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DOI：
10.1152/jn.00010.2009
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发表时间：
2009-06-01
影响因子：
2.5
通讯作者：
Lisberger, Stephen G.
中科院分区：
文献类型：
--
作者：
Huang, Xin;Lisberger, Stephen G.
黄X，利斯伯格SG。皮质区域MT的噪声相关性及其对平滑行李眼运动方向和速度逐审变异的潜在影响。 J Neurophysiol 101：3012-3030，2009年。2009年3月18日首次出版； doi：10.1152/jn.00010.2009。即使在相同的跟踪目标运动重复多次时，平滑行李的眼动动态也是可变的。我们询问追踪的变化是否可能来自中间时间视觉区域（MT）的视觉运动神经元反应的噪声。在生理实验中，我们评估了同时记录的MT神经元对的尖峰计数中的平均值，方差和试验相关性。当一对中的两个神经元具有相似的首选速度，方向或接受场位置时，MT神经元对响应之间的相关性非常明显。当反复出现相同的精确刺激形式时，尖峰计数相关持续存在。随着分析窗口的增加，峰值计数相关性的增加，因为跨时间的单个神经元的响应的相关性。峰值计数相关性在低于神经元对的首选速度的速度下最高，并且随着方波光栅的对比度降低而增加。在计算分析中，我们评估了MT中总体反应之间的相关性和变化是否可以推动追求方向和速度的行为变化。我们创建了模型种群响应，模仿了MT神经反应的平均值和方差，以及观察到的神经元对之间噪声相关的结构和幅度。对载体的解码计算表明，追踪的观察到的变化可能是MT种群反应引起的，而无需假设其他运动差异来源。
Huang X, Lisberger SG. Noise correlations in cortical area MT and their potential impact on trial-by-trial variation in the direction and speed of smooth-pursuit eye movements. J Neurophysiol 101: 3012-3030, 2009. First published March 18, 2009; doi:10.1152/jn.00010.2009. Smooth-pursuit eye movements are variable, even when the same tracking target motion is repeated many times. We asked whether variation in pursuit could arise from noise in the response of visual motion neurons in the middle temporal visual area (MT). In physiological experiments, we evaluated the mean, variance, and trial-by-trial correlation in the spike counts of pairs of simultaneously recorded MT neurons. The correlations between responses of pairs of MT neurons are highly significant and are stronger when the two neurons in a pair have similar preferred speeds, directions, or receptive field locations. Spike count correlation persists when the same exact stimulus form is repeatedly presented. Spike count correlations increase as the analysis window increases because of correlations in the responses of individual neurons across time. Spike count correlations are highest at speeds below the preferred speeds of the neuron pair and increase as the contrast of a square-wave grating is decreased. In computational analyses, we evaluated whether the correlations and variation across the population response in MT could drive the observed behavioral variation in pursuit direction and speed. We created model population responses that mimicked the mean and variance of MT neural responses as well as the observed structure and amplitude of noise correlations between pairs of neurons. A vector-averaging decoding computation revealed that the observed variation in pursuit could arise from the MT population response, without postulating other sources of motor variation.