Somatosensory effects of action inhibition: a study with the stop-signal paradigm
Somatosensory effects of action inhibition: a study with the stop-signal paradigm
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DOI：
10.1007/s00221-010-2181-y
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发表时间：
2010-07-01
影响因子：
2
通讯作者：
Haggard, Patrick
中科院分区：
文献类型：
--
作者：
Walsh, Eamonn;Haggard, Patrick
当一个微弱的电击被送到手指上，紧接着一个自愿的动作，或者在受试者准备做动作的一段延迟时间内，随着动作的临近，电击的检测率逐渐变差。此外，我们之前已经证明，如果NoGo信号对预先准备的反应产生抑制，那么休克检测就会再次改善。在这里，我们使用了一个躯体感觉版本的停止信号范式来研究在运动兴奋和抑制过程可能同时活跃的“赛马”时期的抑制加工。当受试者对GO信号做出快速按键反应时，电击检测会以一种与时间相关的方式恶化，重复感觉抑制。然而，当GO信号之后紧跟着适应性延迟的停止信号，使得受试者无法抑制准备好的动作，并犯下错误时，我们发现在停止信号之后，电击检测性能出现了矛盾的短暂提高，就像在NoGo试验中一样。在这段短暂的时间里，体感系统显示出与运动抑制一致的模式，尽管运动系统本身在运动执行方面太先进了，无法抑制动作。大多数停车信号处理模型提出了一种兴奋和抑制之间的两马赛跑，并提出了赢家通吃的解决方案。我们表明，可能存在不同的运动和躯体感觉种族。此外，抑制性过程可能会导致躯体感觉竞赛，至少是短暂的，即使兴奋过程赢得了汽车竞赛。
When a weak shock is delivered to the finger immediately before a voluntary movement, or during a delay interval where subjects are prepared to make the movement, shock detection rates worsen progressively as the movement approaches. Further, we previously showed that shock detection improves again if a NoGo signal produces inhibition of a prepared response. Here, we used a somatosensory version of the stop-signal paradigm to investigate inhibitory processing during the 'horserace' period when motor excitation and inhibition processes may be simultaneously active. When subjects made a rapid keypress response to a go-signal, shock detection deteriorated in a time-dependent manner, replicating sensory suppression. However, when go-signals were followed by adaptively delayed stop-signals so that subjects could not inhibit the prepared movement, and made errors of commission, we found a paradoxical brief increase in shock detection performance just after the stop-signal, as if in a NoGo trial. During this brief window, the somatosensory system showed a pattern consistent with motor inhibition, even though the motor system itself was too far advanced in movement execution for action to be inhibited. Most models of stop-signal processing propose a two-horse race between excitation and inhibition, with a winner-takes-all solution. We show that there may be distinct motor and somatosensory races. Moreover, inhibitory processes may lead in the somatosensory race, at least briefly, even when excitatory processes win the motor race.