In this study, we sought to characterise the effects of intense sensory stimulation at different stages of preparation for an anticipated action on voluntary and involuntary behaviours. In our experiment, we presented unexpected loud acoustic stimuli (LAS) at four critical times during movement preparation (Baseline, -1192 ms, -392 ms, and 0 ms relative to expected movement onset) to probe the state of the nervous system, and measured their effect on voluntary (finger-press) and involuntary (eye-blink startle reflex) motor actions. Voluntary responses were largely facilitated by the LAS, leading to earlier and more forceful responses compared to Control (without LAS) and Baseline conditions. Notably, voluntary responses were significantly facilitated on trials where the LAS was presented early during preparation (-1192 ms). Eye-blink reflexes elicited by the LAS at -392 ms were significantly reduced and delayed compared to other time-points, indicating suppression of sub-cortical excitability. Despite being in a suppressive state, voluntary responses on these trials were still facilitated by the LAS. The results provide insight into the mechanisms involved in preparing anticipatory actions. Induced activation can persist in the nervous system and can modulate subsequent actions for a longer time period than previously thought, highlighting that movement preparation is a continuously evolving process that is susceptible to external influence throughout the preparation period. Suppression of sub-cortical excitability shortly before movement onset is consistent with previous work showing corticospinal suppression which may be a necessary step before the execution of any voluntary response.

中文翻译：

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在预期的定时任务中对大声声刺激的自愿和非自愿反应的准备性抑制和促进。

在这项研究中，我们试图表征强烈的感觉刺激在准备对自愿和非自愿行为采取预期行动的不同阶段的影响。在我们的实验中，我们展示了运动准备过程中的四个关键时刻（基线，-1192毫秒，-392毫秒和相对于预期运动开始的0毫秒）出乎意料的响亮声刺激（LAS），以探究神经系统的状态，以及测量了它们对自愿（手指按压）和非自愿（眨眼惊吓反射）运动动作的影响。LAS在很大程度上促进了自愿反应，与对照组（无LAS）和基线情况相比，导致了更早，更有力的反应。值得注意的是，在准备过程中（-1192 ms）出现LAS的试验中，自愿应答得到了显着促进。与其他时间点相比，LAS在-392 ms引起的眨眼反射明显减少和延迟，表明抑制了皮层下兴奋性。尽管处于抑制状态，但LAS仍促进了对这些试验的自愿反应。结果提供了对涉及准备预期行动的机制的见解。诱导的激活可以在神经系统中持续存在，并且可以在比以前认为的更长的时间段内调节后续动作，从而突出表明运动准备是一个不断发展的过程，在整个准备过程中容易受到外部影响。