NEURONAL SPECIFICATION OF DIRECTION AND DISTANCE DURING REACHING MOVEMENTS IN THE SUPERIOR PRECENTRAL PREMOTOR AREA AND PRIMARY MOTOR CORTEX OF MONKEYS
NEURONAL SPECIFICATION OF DIRECTION AND DISTANCE DURING REACHING MOVEMENTS IN THE SUPERIOR PRECENTRAL PREMOTOR AREA AND PRIMARY MOTOR CORTEX OF MONKEYS
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DOI：
10.1152/jn.1993.70.5.2097
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发表时间：
1993-11-01
影响因子：
2.5
通讯作者：
EBNER, TJ
中科院分区：
文献类型：
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作者：
FU, QG;SUAREZ, JI;EBNER, TJ
1. 在两只恒河猴执行手臂伸展任务期间，记录了初级运动和上中央前运动区的单单位神经元活动。 该任务涉及使用绘图员的臂式操作器移动视频终端上显示的光标。 动物需要从位于中心的起始箱开始以八个不同方向（0-360 度，以 45 度间隔）和六个距离（1.4-5.4 厘米，以 0.8 厘米增量）移动到 48 个目标箱中的一个。 即将到来的运动的方向和距离都是不可预测的。2． 记录并评估 48 个目标中每一个目标的 197 个手臂运动相关细胞的活动。 组织学检查显示细胞主要位于初级运动皮层或中央前沟周围的运动前区域。每个细胞的放电在运动开始时对齐，并对每个目标进行五次试验的平均。 还确定了包括手部路径速度在内的运动运动学。 任务时间分为三个时期，即运动前阶段（PT）、运动阶段（MT）和总时间（TT = PT + MT）。 对于每个时期，使用各种回归程序将平均发射与运动的方向和距离相关联。3． 方差分析 (ANOVA) 显示，大多数神经元在三个时间段 PT (73.7%)、MT (68.3%) 和 TT (78.5%) 中均受到运动方向的显着调节。 发射与方向的关系适合每个显着调制的细胞的余弦调谐函数。 在 86.3% 的细胞中，放电与 TT 中运动方向的余弦函数显着相关。 对于不同的移动距离，细胞的首选方向变化不大。 对于最小可能的距离变化（0.8 厘米），首选方向的平均差异为 12.8 +/- 11.4 度（SD），对于最大距离变化（4.0 厘米），首选方向的平均差异为 17.1 +/- 14.7 度。4。 相关分析显示，大多数细胞的活性在三个时间段（PT（46.8%）、MT（68.8%）和 TT（67.&%））中的每一个中都受到沿至少一个方向的距离的显着调节。 随后，使用单变量线性回归模型将电池放电量化为距离的函数。 对于具有统计显着相关性 (r>0.8) 的发射与距离的回归，总时间的平均斜率为 3.59 +/-0.17Spikes.s-1.cm-1。 显着的距离调节的存在并不总是与细胞的首选运动方向相关。 接近细胞首选运动方向的运动与距离显着相关的可能性仅略有增加。此外，对于接近细胞首选方向的运动，距离的平均斜率并不更大。5。 使用双向方差分析来测试相对于方向和距离的发射调制，并检查这两个参数之间是否存在相互作用。 在所评估的 153 个细胞中，有 130 个细胞发生了方向、距离或这两个参数之间“相互作用”的显着调节。 模型中的交互项相当于目标位置。接下来，开发了一个多元回归模型，将电池的放电与方向和距离联系起来。 使用比例误差减少 (PRE) 方法来定义模型中的项。 六个必需参数包括距离、方向的正弦和余弦函数以及目标位置。 该模型产生了显着的拟合（P
1. Single-unit neuronal activity was recorded in the primary motor and superior precentral premotor areas of two rhesus monkeys during an arm reaching task. The task involved moving a cursor displayed on a video terminal using a draftsman's armtype manipulandum. From a centrally located start box the animal was required to move to 1 of 48 target boxes at eight different directions (0-360-degrees in 45-degree intervals) and six distances (1.4-5.4 cm in 0.8-cm increments). Both direction and distance for the upcoming movement were unpredictable.2. The activity of 197 arm movement-related cells was recorded and evaluated for each of the 48 targets. Histological examination showed the cells to be primarily in the primary motor cortex or in the premotor area around the superior precentral sulcus. Each cell's discharge was aligned on movement onset and averaged over five trials for each target. Movement kinematics including hand path velocity were also determined. The task time was divided into three epochs, a premovement period (PT), a movement period (MT), and total time (TT = PT + MT). For each epoch the average firing was correlated with the direction and distance of the movement using various regression procedures.3. An analysis of variance (ANOVA) showed that the majority of neurons were modulated significantly by movement direction in each of the three time periods, PT (73.7%), MT (68.3%), and TT (78.5%). The relationship of the firing to direction was fit to a cosine tuning function for each significantly modulated cell. In 86.3% of the cells the firing was correlated significantly with a cosine function of movement direction in TT. A cell's preferred direction varied little for different movement distances. The mean difference in preferred direction for the smallest possible change in distance (0.8 cm) was 12.8 +/- 11.4-degrees (SD) and 17.1 +/- 14.7-degrees for the largest change in distance (4.0 cm).4. Correlation analysis revealed that the activity of the majority of cells was modulated significantly by distance along at least one direction in each of the three time periods, PT (46.8%), MT (68.8%), and TT (67.&%). subsequently, a univariate linear regression model was used to quantify a cell's discharge as a function of distance. For the regressions of firing with distance with a statistically significant correlation (r>0.8), the mean slope was 3.59 +/-0.17 spikes.s-1.cm-1 for the total time. The existence of a significant distance modulation was not invariably correlated with a cell's preferred movement direction. There was only a slight increase in the likelihood of a significant correlation with distance for movements close to a cell's preferred movement direction. Also, the average slope for distance was not greater for movements close to a cell's preferred direction.5. A two-way ANOVA was used to test for firing modulation with respect to direction and distance and to examine whether interactions between these tow parameters exist. Significant modulation with either direction, distance, or ''interaction'' between these two parameters occurred in 130 of 153 cells evaluated. The interaction terms in the model are equivalent to target position. Next, a multivariate regression model was developed to relate the cell's discharge with direction and distance. A proportional reduction in error (PRE) approach was used to define the terms in the model. The six required parameters included distance, a sine and cosine function of direction, and target position. The model yielded a significant fit (P