Milner P M, Laferrière A
Behav Brain Res. 1986 Dec;22(3):217-26. doi: 10.1016/0166-4328(86)90066-5.
A behavioral method for measuring the electrical sensitivity of directly stimulated elements in the brain is described and applied to the medial forebrain bundle (MFB) reward path and the tectospinal circling path. Equations are derived from which threshold current densities may be calculated from knowledge of the electrode tip dimensions and the current required to produce criterion behavior, which is a function of electrode size. Four different sizes of electrode were implanted in the MFB of rats and self-stimulation rates plotted against stimulating current. The mean currents for criterion bar-pressing rates of 25% and 55% of maximum rate were determined for each electrode size and the values used to calculate average threshold current densities. Two sizes of electrode were implanted in the tectospinal tract of rats and the average currents to produce circling at 0.2 and 0.4 turns/s were measured. The threshold current densities for self-stimulation axons were about 5 times as large as those for circling, in accordance with other evidence that tectal circling path axons are larger than those of the MFB reward path.
本文描述了一种测量大脑中直接刺激元件电敏感性的行为方法，并将其应用于内侧前脑束（MFB）奖赏通路和顶盖脊髓环路通路。推导了一些方程，根据电极尖端尺寸和产生标准行为所需的电流（这是电极尺寸的函数）的知识，可以计算出阈值电流密度。将四种不同尺寸的电极植入大鼠的MFB，并绘制自刺激率与刺激电流的关系图。对于每种电极尺寸，确定了达到最大速率的25%和55%的标准压杆率时的平均电流，并使用这些值来计算平均阈值电流密度。将两种尺寸的电极植入大鼠的顶盖脊髓束，并测量产生0.2和0.4转/秒的转圈行为时的平均电流。自刺激轴突的阈值电流密度大约是转圈行为的5倍，这与其他证据一致，即顶盖环路通路的轴突比MFB奖赏通路的轴突更大。
