INFORMATION PROCESSING IN CEREBELLAR FLOCCULUS FUNCTIONAL ZONE

本文研究了警觉猫视动反应（OKR）中小脑小叶中区浦肯野细胞的瞬时单棘波（SS）频率与眼球运动的相关性。给定时间延迟时的时间SS速率的时间过程（平均11 ins），通过眼加速度的线性加权叠加，确定系数> 0.7（平均系数，0.076尖峰/秒/度/秒2），速度（5.19 spikes/s per deg/s），位置（-2.89峰值/秒/度）和偏差（平均值，35.8个尖峰/秒），估计每个分量对回归的贡献大小，发现三种细胞类型：速度-位置-加速度（VPA）类型（n=19），速度、位置和加速度分量的贡献显著速度-位置（VP）型（n=9），速度和位置分量显著;速度-加速度（VA）型（n=2），速度和加速度分量显著。使用一组系数为5度/秒的刺激速度，在较高的刺激速度（10，20，和40度/秒）的SS率被成功地重建，这表明该模型的通用性。在OKR期间在SS发射中编码的眼睛位置信息是相对的，但不是绝对的，在这个意义上，位置偏移的幅度有助于发射率变化，而不管初始眼睛位置。结论是：1）在短持续时间水平OKR期间，猫中间区的时间SS-发射频率编码了速度和加速度信息，分别用于控制粘性力和惯性力; 2）在SS-发射中编码的位置信息不足以控制OKR期间的弹性力。

We investigated correlation between the eye movement and temporal simple-spike (SS) frequency of the Purkinje cell in the cerebellar flocculus middle-zone during optokinetic response (OKR) in alert cats. Time course of the temporal SS-rate at a given time delay (mean, 11 ins) was well reconstructed with coefficient of determination > 0.7 by a linear weighted superposition of the eye acceleration (mean coefficient, 0.076 spikes/s per deg/s2), velocity (5.19 spikes/s per deg/s), position (-2.89 spikes/s per deg), and bias (mean, 35.8 spikes/s), Magnitude of the contribution of each component to the regression was estimated, and three cell types were found : Velocity-Position-Acceleration (VPA) type (n=19), contribution of velocity, position, and acceleration components is significant (P < 0.05) ; Velocity-Position (VP) type (n=9), velocity and position components are significant ; Velocity-Acceleration (VA) type (n=2), velocity and acceleration components are significant. Using a single set of the coefficients for 5 deg/s stimulus velocity, the SS rate during higher (10, 20, and 40 deg/s) stimulus velocities were successfully reconstructed, suggesting generality of the model. The eye-position information encoded in SS-firing during OKR is relative but not absolute in the sense that the magnitude of the position shift contributes to the firing-rate change regardless of the initial eye-position. It is concluded that 1) the temporal SS-firing frequency in the cat middle-zone encodes the velocity and acceleration information for controlling the viscosity- and inertia-forces, respectively, during short-duration horizontal OKR and 2) the position information encoded in the SS-firing is not sufficient for controlling the elastic force during] OKR.