Event Lab, Department of Clinical Psychology and Psychobiology, Faculty of Psychology, Barcelona, Spain.
Institute of Neurosciences, University of Barcelona, 08035, Barcelona, Spain.
Sci Rep. 2017 Oct 27;7(1):14227. doi: 10.1038/s41598-017-14620-5.
Previous results have shown that body ownership, induced through first-person perspective (1PP) over a virtual body (VB) that moves synchronously with real body movements, can lead to illusory agency over VB utterances even though the participant does not speak. It was also found that when participants later speak they follow the fundamental frequency (FF) of the voice of their VB, indicating a new motor plan for speaking. To eliminate the contribution of veridical agency over the VB movements, we conducted a study where we induced body ownership using visuotactile (VT) synchrony rather than visuomotor. Participants saw a life-sized VB from 1PP and reflected in a virtual mirror, that spoke with corresponding lip movements. Half of the 36 experimental participants experienced synchronous (Sync) passive VT on their hands and abdomen, and the other half asynchronous (Async). We found that both VT Sync and Async conditions resulted in a strong subjective illusion of body ownership and agency over the VB, but not, however, changes in voice FF in subsequent speaking. This shows that although illusory agency may be associated with body ownership, a change in motor plan is likely to be a generalisation from veridical agency over whole body movements.
先前的研究结果表明，通过与真实身体运动同步移动的虚拟身体（VB）的第一人称视角（1PP），可以诱导身体所有权，从而导致对 VB 话语的虚幻代理权，即使参与者不说话。还发现，当参与者稍后说话时，他们会跟随 VB 声音的基频（FF），这表明他们有新的说话运动计划。为了消除对 VB 运动的真实代理权的影响，我们进行了一项研究，使用视觉触觉（VT）同步而不是运动视觉来诱导身体所有权。参与者从 1PP 看到一个真人大小的 VB，并在虚拟镜子中反射，并用相应的嘴唇动作说话。36 名实验参与者中的一半经历了手部和腹部的同步（Sync）被动 VT，另一半经历了异步（Async）。我们发现，VT Sync 和 Async 条件都导致了对 VB 的强烈的身体所有权和代理权的主观错觉，但随后说话时的声音 FF 并没有改变。这表明，尽管虚幻的代理权可能与身体所有权有关，但运动计划的改变很可能是从整个身体运动的真实代理权中概括出来的。
