Yeomans J S, Pearce R, Wen D, Hawkins R D
Physiol Behav. 1984 Feb;32(2):287-94. doi: 10.1016/0031-9384(84)90143-4.
Electrical stimulation applied near the medial longitudinal fasciculus (MLF) produces ipsiversive circling. In this experiment we examined the spatial and temporal properties of this substrate in rats by determining the current required to produce a constant amount of circling at frequencies from 15 to 500 Hz. In general, when frequency was high, the required current was low and vice versa, but there were deviations from a reciprocal relationship. Frequencies above 200 Hz failed to reduce the current needed to reach criterion. Electrodes placed distant from the MLF required more current, and deviated from reciprocity in a systematic way. A geometric model of the overlap between substrate and stimulation field is proposed that allows estimation of spatial properties of the two regions: (1) the location of the center of the substrate for circling (0.7 mm lateral, 7.0 mm below dura in the coronal plane 1.0 mm posterior to ear bars); (2) the radius of the substrate (0.77 mm); and (3) the radius of excitation at each current. Current-frequency trade off data can provide an in vivo estimate of the behavioral effectiveness of a given electrode, and hence its placement relative to a behavioral substrate.
在内侧纵束（MLF）附近施加电刺激会产生同侧旋转。在本实验中，我们通过确定在15至500赫兹频率下产生恒定旋转量所需的电流，研究了大鼠中该基质的空间和时间特性。一般来说，当频率较高时，所需电流较低，反之亦然，但存在偏离反比关系的情况。高于200赫兹的频率未能降低达到标准所需的电流。放置在远离MLF的电极需要更多电流，并且以系统的方式偏离反比关系。提出了一个基质与刺激场重叠的几何模型，该模型允许估计两个区域的空间特性：（1）旋转基质中心的位置（在冠状平面内，耳杆后方1.0毫米处，硬脑膜下方7.0毫米，外侧0.7毫米）；（2）基质的半径（0.77毫米）；以及（3）每种电流下的兴奋半径。电流-频率权衡数据可以提供给定电极行为有效性的体内估计，从而提供其相对于行为基质的放置情况。
