英国伦敦大学学院等机构的研究人员在最新《科学公共图书馆·综合》（PLoS ONE）网络期刊上报告说，他们设计了一套虚拟现实系统，可使男性受试者感到拥有一个虚拟的女性身体。
领导研究的斯莱特教授说，一个人的大脑是如何认知自己身体的问题一直受到科学界关注，这项研究说明，只要令视觉和触觉协调一致，可以使男性受试者感到拥有虚拟女性的身体。相关技术除了应用于科学研究外，还有望在医疗领域帮助那些对自身躯体认知失常的病人，此外也可用于娱乐等领域。
受试者被要求戴上一个虚拟现实头盔，头盔中显示的是一间虚拟的房屋，屋里有一名年长女性和一名年轻女孩，年长女性正在抚摸年轻女孩的手臂。
在受试者熟悉这个虚拟环境后，头盔中显示的内容被切换成女孩的视角，当受试者低头看自己时，映入眼中的会是这名女孩的身体，如果在这个虚拟环境中照镜子，也会看到这名女孩的样子。与此同时，当虚拟的年长女性触碰女孩手臂时，受试者的手臂上也被施加了相似的触觉。这样，受试者大脑收到的视觉和触觉信号得到协调，都与虚拟的环境一致。
沉浸在这种环境中一段时间后，受试者报告说他们感到一种错觉，似乎自己拥有的就是这名虚拟的女孩的身体。而客观上对受试者心率的测量也显示，在虚拟环境中年长女性突然打了女孩一巴掌的时候，受试者的心率也相应出现了变化。(生物谷Bioon.com)
生物谷推荐原文出处：
PLoS ONE doi:10.1371/journal.pone.0010564
First Person Experience of Body Transfer in Virtual Reality
Mel Slater1,2,3*, Bernhard Spanlang2,4, Maria V. Sanchez-Vives1,5, Olaf Blanke6
1 Institució Catalana Recerca i Estudis Avan?ats (ICREA), Universitat de Barcelona, Barcelona, Spain, 2 Facultat de Psicologia, Universitat de Barcelona, Barcelona, Spain, 3 Department of Computer Science, University College London, London, United Kingdom, 4 Departament de LSI, Universitat Politècnica de Catalunya, Barcelona, Spain, 5 Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain, 6 Brain-Mind Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
Background
Altering the normal association between touch and its visual correlate can result in the illusory perception of a fake limb as part of our own body. Thus, when touch is seen to be applied to a rubber hand while felt synchronously on the corresponding hidden real hand, an illusion of ownership of the rubber hand usually occurs. The illusion has also been demonstrated using visuomotor correlation between the movements of the hidden real hand and the seen fake hand. This type of paradigm has been used with respect to the whole body generating out-of-the-body and body substitution illusions. However, such studies have only ever manipulated a single factor and although they used a form of virtual reality have not exploited the power of immersive virtual reality (IVR) to produce radical transformations in body ownership.
Principal Findings
Here we show that a first person perspective of a life-sized virtual human female body that appears to substitute the male subjects' own bodies was sufficient to generate a body transfer illusion. This was demonstrated subjectively by questionnaire and physiologically through heart-rate deceleration in response to a threat to the virtual body. This finding is in contrast to earlier experimental studies that assume visuotactile synchrony to be the critical contributory factor in ownership illusions. Our finding was possible because IVR allowed us to use a novel experimental design for this type of problem with three independent binary factors: (i) perspective position (first or third), (ii) synchronous or asynchronous mirror reflections and (iii) synchrony or asynchrony between felt and seen touch.
Conclusions
The results support the notion that bottom-up perceptual mechanisms can temporarily override top down knowledge resulting in a radical illusion of transfer of body ownership. The research also illustrates immersive virtual reality as a powerful tool in the study of body representation and experience, since it supports experimental manipulations that would otherwise be infeasible, with the technology being mature enough to represent human bodies and their motion.
