Xenomelia: A social neuroscience view of altered bodily self-consciousness

Abstract

Xenomelia, the "foreign limb syndrome," is characterized by the non-acceptance of one or more of one's own extremities and the resulting desire for elective limb amputation or paralysis. Formerly labeled "body integrity identity disorder" (BIID), the condition was originally considered a psychological or psychiatric disorder, but a brain-centered Zeitgeist and a rapidly growing interest in the neural underpinnings of bodily self-consciousness has shifted the focus toward dysfunctional central nervous system circuits. The present article outlays both mind-based and brain-based views highlighting their shortcomings. We propose that full insight into what should be conceived a "xenomelia spectrum disorder" will require interpretation of individual symptomatology in a social context. A proper social neuroscience of xenomelia respects the functional neuroanatomy of corporeal awareness, but also acknowledges the brain's plasticity in response to an individual's history, which is lived against a cultural background. This integrated view of xenomelia will promote the subfield of consciousness research concerned with the unity of body and self. In times when an author can barely write about cognition without emphasizing its "embodied" aspects, it seems especially compelling to consider body-brain interactions in the field of consciousness studies or the cognitive neuroscience of "the self." In fact, philosophers and scientists agree that knowledge about how the brain processes bodily sensations and plans executive action is key to the understanding of the experience of being a conscious self (Blanke and Metzinger, 2009). However, an individual's bodily self-consciousness is not fully predefined by genes and neural circuits. It is constantly compared with others' relationships to their bodies and evaluated against cultural norms about bodily appearance. In this article we will review work on xenomelia, one variant of the normal relationships between body and self, that is the desire of a healthy individual to have a fully functional limb amputated. We propose a social neuroscience of xenomelia that unifies neurological, psychological, and sociological approaches to bodily self-consciousness.