Lineberry C G, Vierck C J
Brain Res. 1975 Nov 7;98(1):119-34. doi: 10.1016/0006-8993(75)90513-2.
The effect of caudate nucleus stimulation on reactivity to painful stimuli was investigated in Macaca speciosa monkeys chronically implanted with electrodes in the right caudate nucleus. The force with which subjects escaped from electrocutaneous leg shock was used as a measure of pain reactivity and was decreased by caudate stimulation. Escape threshold and latencies were not influenced by the brain stimulation. Decreased escape force was obtained only when 50 msec trains of caudate stimulation preceded 20 msec trains of leg shock by 0-100 msec. Pain reactivity was not affected if brain stimulation followed leg shock or if leg shock followed brain stimulation by more than 100 msec. Intershock response distributions indcated that direct motor inhibition was not responsible for the depression of escape force, and the effectiveness of a restricted range of caudate-leg stimulation intervals ruled out generalized effects on arousal. The results indicate that the effect of caudate stimulation is to reduce the affective components of pain elicited by noxious electrocutaneous stimuli. The time course of this caudate effect parallels that previously reported for the caudate-induced depression of evoked activity in the non-specific somatosensory projections of the reticular formation and thalamus.
在右侧尾状核长期植入电极的戴帽叶猴中，研究了尾状核刺激对疼痛刺激反应性的影响。将实验对象逃避腿部皮肤电休克的力量用作疼痛反应性的衡量指标，尾状核刺激会使其降低。逃避阈值和潜伏期不受脑部刺激的影响。只有当50毫秒的尾状核刺激序列在20毫秒的腿部电击序列之前0 - 100毫秒出现时，才会出现逃避力量下降的情况。如果脑部刺激在腿部电击之后出现，或者腿部电击在脑部刺激之后超过100毫秒出现，疼痛反应性则不受影响。电击间隔反应分布表明，直接的运动抑制并非逃避力量降低的原因，并且有限范围的尾状核 - 腿部刺激间隔的有效性排除了对觉醒的广泛影响。结果表明，尾状核刺激的作用是减少有害皮肤电刺激引发的疼痛的情感成分。这种尾状核效应的时间进程与先前报道的尾状核诱导的网状结构和丘脑非特异性体感投射中诱发活动抑制的时间进程相似。
