Institute of Cognitive Neuroscience, University College London, London, UK.
Department of Biomedical Engineering, Hanyang University, Seoul, South Korea.
Neuroimage. 2019 Nov 15;202:116140. doi: 10.1016/j.neuroimage.2019.116140. Epub 2019 Aug 29.
An experience of intention to move accompanies execution of some voluntary actions. The Readiness Potential (RP) is an increasing negativity over motor brain areas prior to voluntary movement. Classical studies suggested that the RP starts before intention is consciously accessed as measured by offline recall-based reports, yet the interpretation of the RP and its temporal relation to awareness of intention remain controversial. We designed a task in which self-paced actions could be interrupted at random times by a visual cue that probed online awareness of intention. Participants were instructed to respond by pressing a key if they felt they were actively preparing a self-paced movement at the time of the cue (awareness report), but to ignore the cue otherwise. We show that an RP-like activity was more strongly present before the cue for probes eliciting awareness reports than otherwise. We further show that recall-based reports of the time of conscious intention are linked to visual attention processes, whereas online reports elicited by a probe are not. Our results suggest that awareness of intention is accessible at relatively early stages of motor preparation and that the RP is specifically associated with this conscious experience.
意图运动的体验伴随着某些自愿运动的执行。准备电位(RP)是在自愿运动之前,大脑运动区域的负性增加。经典研究表明,RP 先于意图被有意识地访问,这可以通过离线基于回忆的报告来衡量,但 RP 的解释及其与意图意识的时间关系仍然存在争议。我们设计了一个任务,其中自我调节的动作可以在任意时间被一个视觉提示打断,这个提示会在线探测意图的意识。参与者被指示,如果他们在提示时感觉到自己正在积极准备自我调节的动作(意识报告),就按下一个键,否则忽略提示。我们表明,与否则相比,在提示前,与意识报告相关的探测中,RP 样的活动更为强烈。我们进一步表明,基于回忆的对有意识意图的时间的报告与视觉注意过程有关,而由探测引发的在线报告则没有。我们的结果表明,意图的意识可以在运动准备的相对早期阶段获得,并且 RP 与这种意识体验密切相关。