Preston Catherine, Ehrsson H Henrik
Brain, Body and Self Laboratory, Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.
PLoS One. 2014 Jan 21;9(1):e85773. doi: 10.1371/journal.pone.0085773. eCollection 2014.
Historically, body size overestimation has been linked to abnormal levels of body dissatisfaction found in eating disorders. However, recently this relationship has been called into question. Indeed, despite a link between how we perceive and how we feel about our body seeming intuitive, until now lack of an experimental method to manipulate body size has meant that a causal link, even in healthy participants, has remained elusive. Recent developments in body perception research demonstrate that the perceptual experience of the body can be readily manipulated using multisensory illusions. The current study exploits such illusions to modulate perceived body size in an attempt to influence body satisfaction. Participants were presented with stereoscopic video images of slimmer and wider mannequin bodies viewed through head-mounted displays from first person perspective. Illusory ownership was induced by synchronously stroking the seen mannequin body with the unseen real body. Pre and post-illusion affective and perceptual measures captured changes in perceived body size and body satisfaction. Illusory ownership of a slimmer body resulted in participants perceiving their actual body as slimmer and giving higher ratings of body satisfaction demonstrating a direct link between perceptual and affective body representations. Change in body satisfaction following illusory ownership of a wider body, however, was related to degree of (non-clinical) eating disorder psychopathology, which can be linked to fluctuating body representations found in clinical samples. The results suggest that body perception is linked to body satisfaction and may be of importance for eating disorder symptomology.
从历史上看，身体尺寸高估一直与饮食失调中发现的异常身体不满水平有关。然而，最近这种关系受到了质疑。的确，尽管我们对身体的感知与感受之间的联系似乎很直观，但直到现在，由于缺乏一种操纵身体尺寸的实验方法，这意味着即使在健康参与者中，因果关系也仍然难以捉摸。身体感知研究的最新进展表明，身体的感知体验可以通过多感官错觉轻易地被操纵。当前的研究利用这些错觉来调节感知到的身体尺寸，试图影响身体满意度。参与者通过头戴式显示器从第一人称视角观看更瘦和更宽的人体模型的立体视频图像。通过用未被看到的真实身体同步抚摸所看到的人体模型身体来诱发错觉性拥有感。错觉前后的情感和感知测量捕捉了感知到的身体尺寸和身体满意度的变化。对更瘦身体的错觉性拥有感导致参与者将他们的实际身体感知为更瘦，并给予更高的身体满意度评分，这表明了感知和情感身体表征之间的直接联系。然而，对更宽身体的错觉性拥有感之后身体满意度的变化与（非临床）饮食失调心理病理学的程度有关，这可能与临床样本中发现的波动的身体表征有关。结果表明，身体感知与身体满意度有关，可能对饮食失调症状学很重要。
