Experimental Psychology, Helmholtz Institute, Utrecht University, Utrecht, The Netherlands.
Experimental Psychology, Helmholtz Institute, Utrecht University, Utrecht, The Netherlands.
Neuropsychologia. 2018 Aug;117:418-427. doi: 10.1016/j.neuropsychologia.2018.07.012. Epub 2018 Jul 18.
Body ownership (the feeling that my body belongs to me) can be easily perturbed in healthy individuals by inducing bodily illusions. For example, dis-integrating vision, touch, and proprioception can produce the feeling that your limb is 'lost', such as in "the disappearing hand trick" (DHT). Following this illusion, participants report that the hand feels as though it is no longer part of the body, that it does not belong to them anymore, and that they do not know its location. However, it remains unknown whether this illusion can also be applied to the feet. Lower body ownership is disturbed in some populations, such as in Body Integrity Identity Disorder (BIID), where people have a longstanding desire to paralyze or amputate a (disowned) part of their body (i.e. usually the legs), thus exploring the efficacy and utility of lower body illusions might be useful for populations like such. In the current study, we induced the disappearing hand and foot trick in two groups of healthy adults. As the illusion crucially relies on illusory sensory feedback, we also explored if one's level of sensory suggestibility influenced the experience of the illusion. Questionnaire data showed that the DHT can be applied to the feet, as there was no difference in experience between those who experienced the illusion for the hands and those who experienced the illusion for the feet. Moreover, one's level of sensory suggestibility correlated positively with the experience of illusory sensations (like warmth, numbness, or the presence of an extra limb) following the illusion. We discuss the implications of bodily illusions in clinical populations and emphasize the critical role that sensory signals (even illusory) play in creating the bodily experience.
身体所有权（感觉自己的身体属于自己）可以通过诱导身体错觉很容易地在健康个体中受到干扰。例如，视觉、触觉和本体感觉的分离会产生肢体“丢失”的感觉，例如在“消失的手把戏”（DHT）中。在这种错觉之后，参与者报告说手感觉不再是身体的一部分，不再属于他们，他们不知道手的位置。然而，目前还不清楚这种错觉是否也可以应用于脚。身体下部的所有权在某些人群中受到干扰，例如在身体完整性认同障碍（BIID）中，人们长期以来一直渴望瘫痪或截肢自己身体的一部分（即通常是腿），因此探索下肢错觉的效果和实用性可能对这样的人群有用。在当前的研究中，我们在两组健康成年人中诱导了消失的手和脚把戏。由于错觉关键依赖于错觉的感觉反馈，我们还探讨了一个人的感觉暗示水平是否会影响错觉的体验。问卷调查数据显示，DHT 可以应用于脚，因为对于那些经历过手的错觉和那些经历过脚的错觉的人来说，体验没有区别。此外，一个人的感觉暗示水平与错觉后产生的错觉感觉（如温暖、麻木或存在额外的肢体）呈正相关。我们讨论了身体错觉在临床人群中的意义，并强调了感觉信号（即使是错觉）在创造身体体验中所起的关键作用。
