Seyal M, Masuoka L K, Browne J K
Department of Neurology, University of California, Davis Medical Center, Sacramento 95817.
Electroencephalogr Clin Neurophysiol. 1992 Dec;85(6):397-401. doi: 10.1016/0168-5597(92)90053-e.
We have demonstrated that magnetic pulse stimulation of the sensorimotor cortex suppresses perception of threshold electrical stimuli to the fingers of the contralateral hand. Maximum suppression of perception occurs when the fingers are stimulated 30-90 msec after the magnetic pulse. Thereafter, errors in perception of the cutaneous stimulus decrease to control levels by 300-400 msec after the magnetic pulse. The period of maximum suppression of perception coincides with the period during which cortically generated somatosensory evoked potentials (SEPs) are enhanced following magnetic pulse stimulation of the brain. The duration of suppression of perception, however, outlasts the duration of SEP enhancement. When the magnetic pulse is delivered after finger stimulation there is also suppression of perception. The suppression of perception is maximal when the magnetic pulse occurs 20-30 msec after finger stimulation. This interval coincides with the arrival of the afferent volley at the primary sensory cortex.
我们已经证明，对感觉运动皮层进行磁脉冲刺激会抑制对同侧手手指的阈下电刺激的感知。当在磁脉冲后30 - 90毫秒刺激手指时，感知抑制达到最大值。此后，在磁脉冲后300 - 400毫秒，皮肤刺激感知误差降至对照水平。感知抑制的最大时期与大脑磁脉冲刺激后皮层产生的体感诱发电位（SEP）增强的时期一致。然而，感知抑制的持续时间比SEP增强的持续时间更长。当在手指刺激后施加磁脉冲时，也会出现感知抑制。当磁脉冲在手指刺激后20 - 30毫秒出现时，感知抑制最大。这个间隔与传入冲动到达初级感觉皮层的时间一致。
