Rao Isa S, Kayser Christoph
Institute of Neuroscience and Psychology, University of GlasgowGlasgow, United Kingdom.
Front Hum Neurosci. 2017 Jul 25;11:377. doi: 10.3389/fnhum.2017.00377. eCollection 2017.
The rubber hand illusion (RHI) allows insights into how the brain resolves conflicting multisensory information regarding body position and ownership. Previous neuroimaging studies have reported a variety of neurophysiological correlates of illusory hand ownership, with conflicting results likely originating from differences in experimental parameters and control conditions. Here, we overcome these limitations by using a fully automated and precisely-timed visuo-tactile stimulation setup to record evoked responses and oscillatory responses in participants who felt the RHI. Importantly, we relied on a combination of experimental conditions to rule out confounds of attention, body-stimulus position and stimulus duration and on the combination of two control conditions to identify neurophysiological correlates of illusory hand ownership. In two separate experiments we observed a consistent illusion-related attenuation of ERPs around 330 ms over frontocentral electrodes, as well as decreases of frontal alpha and beta power during the illusion that could not be attributed to changes in attention, body-stimulus position or stimulus duration. Our results reveal neural correlates of illusory hand ownership in late and likely higher-order rather than early sensory processes, and support a role of premotor and possibly intraparietal areas in mediating illusory body ownership.
橡胶手错觉(RHI)有助于深入了解大脑如何解决有关身体位置和所属感的相互冲突的多感官信息。先前的神经影像学研究报告了各种与虚幻手部所属感相关的神经生理关联,结果相互矛盾可能源于实验参数和控制条件的差异。在此,我们通过使用全自动且定时精确的视觉-触觉刺激装置来记录产生橡胶手错觉的参与者的诱发反应和振荡反应,从而克服了这些局限性。重要的是,我们依靠多种实验条件的组合来排除注意力、身体-刺激位置和刺激持续时间的混淆因素,并依靠两种控制条件的组合来确定虚幻手部所属感的神经生理关联。在两个独立的实验中,我们观察到在额中央电极周围约330毫秒处,与错觉相关的ERP持续衰减,以及在错觉期间额叶α和β功率的降低,这些变化不能归因于注意力、身体-刺激位置或刺激持续时间的改变。我们的结果揭示了在后期且可能是高阶而非早期感觉过程中虚幻手部所属感的神经关联,并支持运动前区以及可能的顶内区在介导虚幻身体所属感中的作用。