Meers Rosie, Nuttall Helen E, Vogt Stefan
Department of Psychology, Lancaster University, Lancaster, UK.
Department of Psychology, Lancaster University, Lancaster, UK.
Cortex. 2020 May;126:322-333. doi: 10.1016/j.cortex.2020.01.012. Epub 2020 Feb 1.
We studied the motor simulation processes involved in concurrent action observation and motor imagery (AO+MI) using motor evoked potentials induced by transcranial magnetic stimulation. During congruent AO+MI, participants were shown videos of a model's hand performing rhythmical finger movements, and they imagined moving the same finger of their own hand in synchrony with the observed finger. During incongruent AO+MI, the imagery task involved a different finger from the observed one. As expected, congruent AO+MI yielded robust facilitatory effects, relative to baseline, only in the effector involved in the task. Incongruent AO+MI produced equally pronounced effects in the effector that was engaged in MI, whilst no corticospinal facilitation was found for the effector corresponding to the observed action. We further replicated that engaging in pure AO without MI does not produce reliable effects. These results do not support the proposal that observed and imagined action are both simulated at the level of the primary motor cortex. Rather, motor imagery alone can sufficiently explain the observed effects in both AO+MI conditions. This bears clear implications for the application of AO+MI procedures in sport and neurorehabilitation.
我们使用经颅磁刺激诱发的运动诱发电位，研究了同时进行动作观察和运动想象（AO+MI）时所涉及的运动模拟过程。在一致性AO+MI过程中，向参与者展示模型手部进行有节奏手指运动的视频，他们想象自己手部的同一根手指与观察到的手指同步移动。在不一致性AO+MI过程中，想象任务涉及与观察到的手指不同的另一根手指。正如预期的那样，相对于基线，一致性AO+MI仅在任务所涉及的效应器中产生了强烈的促进作用。不一致性AO+MI在参与运动想象的效应器中产生了同样明显的效应，而对应于观察到动作的效应器未发现皮质脊髓促进作用。我们进一步重复验证，仅进行无运动想象的单纯动作观察不会产生可靠的效应。这些结果不支持在初级运动皮层水平同时模拟观察到的动作和想象动作的提议。相反，仅运动想象就能充分解释在两种AO+MI条件下观察到的效应。这对AO+MI程序在运动和神经康复中的应用具有明确的启示。
