LTD-like plasticity induced by paired associative stimulation: direct evidence in humans
LTD-like plasticity induced by paired associative stimulation: direct evidence in humans
复制标题
DOI：
10.1007/s00221-009-1774-9
复制
发表时间：
2009-04-01
影响因子：
2
通讯作者：
Tonali, P. A.
中科院分区：
文献类型：
--
作者：
Di Lazzaro, Vincenzo;Dileone, M.;Tonali, P. A.
配对联想刺激(PAS)，即周围神经刺激之后是运动皮质的经颅磁刺激(TMS)，可能会导致皮质兴奋性的长期变化。在比传入输入到达大脑皮层所需的时间(10ms)稍短的刺激间间隔，运动皮质的兴奋性降低。间接数据支持这一假说，即在此间隔(PAS10)的PAS涉及皮质突触的LTD样变化。本论文的目的是更直接地研究PAS10的影响。我们记录了两名清醒受试者在PAS10前后由单脉冲TMS诱发的皮质脊髓下行抽动，这些受试者植入了高颈硬膜外电极用于止痛。这些同步抽射提供了一种皮质突触活动的测量方法。PAS10可显著降低晚期下降波的波幅，但对最早的下降波无明显影响。目前的结果证实了PAS10效应的皮质起源。
Paired associative stimulation (PAS), in which peripheral nerve stimuli are followed by transcranial magnetic stimulation (TMS) of the motor cortex, may produce a long lasting change in cortical excitability. At an interstimulus interval slightly shorter than the time needed for the afferent inputs to reach cerebral cortex (10 ms), motor cortex excitability decreases. Indirect data support the hypothesis that PAS at this interval (PAS10) involves LTD like-changes in cortical synapses. The aim of present paper was to investigate more directly PAS10 effects. We recorded corticospinal descending volleys evoked by single pulse TMS before and after PAS10 in two conscious subjects who had a high cervical epidural electrode implanted for pain control. These synchronous volleys provide a measure of cortical synaptic activity. PAS10 significantly reduced the amplitude of later descending waves while the earliest descending wave was not modified. Present results confirm the cortical origin of the effect of PAS10.