Bergmann Til Ole, Mölle Matthias, Marshall Lisa, Kaya-Yildiz Leval, Born Jan, Roman Siebner Hartwig
Department of Neurology, Christian-Albrechts University Kiel, Schittenhelmstrasse 10, D-24105 Kiel, Germany.
Eur J Neurosci. 2008 May;27(9):2241-9. doi: 10.1111/j.1460-9568.2008.06178.x.
Paired associative stimulation (PAS) repeatedly pairs electrical nerve stimulation with transcranial magnetic stimulation of the contralateral motor hand area (M1(HAND)). Depending on the interstimulus interval, PAS can induce a long-term potentiation (LTP)-like facilitation or long-term depression (LTD)-like suppression of cortical excitability. In three experimental sessions, 12 awake men received PAS of the right median nerve and left M1(HAND) in the evening before sleep. To optimize the timing of paired stimulation in M1(HAND), the interstimulus interval of PAS was adjusted to the individual N20-latency of the somatosensory evoked potential to induce LTP-like effects (PAS(N20+2ms)), LTD-like effects (PAS(N20-5ms)), or no timing-dependent after-effects (PAS(control)). Motor-evoked potentials (MEPs) showed high interindividual variations in the conditioning effects of PAS(N20+2ms) and PAS(N20-5ms) on cortical excitability. However, PAS(control) allowed us to adjust for any unspecific stimulation effects and the MEP increase after PAS(N20+2ms) differed significantly from the MEP decrease after PAS(N20-5ms). PAS(N20+2ms) and PAS(N20-5ms) also had a differential effect on regional expression of slow waves and slow spindle activity during the first hour of subsequent non-rapid eye movement (NREM) sleep. At the electrode sites overlying the conditioned M1(HAND) and the adjacent premotor cortex, local expression of slow spindle activity was significantly correlated with interindividual differences in the efficacy of PAS(N20+2ms) and PAS(N20-5ms) to potentiate or suppress cortical excitability. This correlation indicates that PAS shapes the local regulation of slow sleep spindles during subsequent NREM sleep.
配对联想刺激（PAS）将电神经刺激与对侧运动手部区域（M1（手部））的经颅磁刺激反复配对。根据刺激间隔时间，PAS可诱导皮层兴奋性出现类似长时程增强（LTP）的易化或类似长时程抑制（LTD）的抑制。在三个实验环节中，12名清醒男性在睡前接受右侧正中神经和左侧M1（手部）的PAS。为了优化M1（手部）配对刺激的时间，将PAS的刺激间隔时间调整为体感诱发电位的个体N20潜伏期，以诱导类似LTP的效应（PAS（N20 + 2毫秒））、类似LTD的效应（PAS（N20 - 5毫秒））或无时间依赖性后效应（PAS（对照））。运动诱发电位（MEP）在PAS（N20 + 2毫秒）和PAS（N20 - 5毫秒）对皮层兴奋性的条件效应中显示出高度个体差异。然而，PAS（对照）使我们能够调整任何非特异性刺激效应，且PAS（N20 + 2毫秒）后MEP的增加与PAS（N20 - 5毫秒）后MEP的降低有显著差异。PAS（N20 + 2毫秒）和PAS（N20 - 5毫秒）对随后非快速眼动（NREM）睡眠的第一个小时内慢波和慢纺锤波活动的区域表达也有不同影响。在受条件刺激的M1（手部）及相邻运动前皮层上方的电极部位，慢纺锤波活动的局部表达与PAS（N20 + 2毫秒）和PAS（N20 - 5毫秒）增强或抑制皮层兴奋性的功效个体差异显著相关。这种相关性表明，PAS塑造了随后NREM睡眠期间慢睡眠纺锤波的局部调节。
