Embodiment, ownership and disownership☆
Introduction
Our body may be the object we know the best, from which we constantly receive a flow of information from vision, touch, proprioception, the vestibular and the interoceptive systems. Not only do we receive more information on our body than on any other objects, but we also have an internal access to it that we have to no other bodies. What makes our body so special may thus be that unlike other physical objects and other bodies, we perceive it from the inside. Only in our body, or at least in what we represent as our own body, do we feel bodily sensations. We also care for our body like we care for no other bodies, let alone other objects. Finally, it seems that it is only our own body that obeys our will with no intermediary.
Yet, the relation between the body and the self is complex, giving rise to vivid philosophical debates (see Table 1).
Some debates have been going on for centuries like questions about the ontological nature of the self and personal identity or about the epistemological certainty we have that this is our own body with no possible doubt. Other debates have emerged from recent scientific progress like issues about the moral and legal status of body parts in a time of research on biological materials or questions about the sensory and cognitive underpinnings of the sense of body ownership following a booming of studies in cognitive psychology and neuropsychology these last 10 years.
Here, I shall set the agenda for the investigation of the sense of ownership of body parts.1 I shall focus on two main pathways, through the study of embodiment and through the study of disownership (see Table 2). However, the relation between embodiment, ownership and disownership is too often left unarticulated. In the paper, I shall bring out some of the main lines of force in this literature and lay the foundation for a proper theory of the sense of ownership. Two questions are of particular interest. First, are embodiment and ownership a matter of all-or-nothing or does it come in degrees or in various types? Second, what is the relationship between experiences of ownership and experiences of disownership?
Section snippets
The sense of body ownership
Before investigating the grounds of the sense of body ownership, one must distinguish between feeling of ownership and judgement of ownership (for a similar distinction within the sense of agency, see Bayne & Pacherie, 2007). Some philosophers, however, take the sense of ownership to be exclusively judgmental (Bermudez, in press). On the deflationary conception of ownership, there is no such thing as a feeling of body ownership, that is, a positive phenomenology of ‘myness’ that goes beyond the
The measures of embodiment
The definition of embodiment in terms of the types of processing that characterize the representation of one’s body does not inform us about the specific way the properties of one’s body are processed. One possible strategy to address this question is to analyse the various attempts to operationalize the notion of embodiment in clinical and experimental studies. Unfortunately, most studies on amputees merely rate the patients’ degree of satisfaction with the graft or the prosthesis or the
The manifold of embodiment
There are many differences between the artificial embodiment of allograft, prostheses, rubber hands, virtual avatars and tools, and at various levels. To start with, some artificial embodiments occur in amputees with missing limbs (e.g., graft, prosthesis), while others occur in healthy individuals with a fully functioning body (e.g., RHI; virtual avatar). What is embodied can be the whole body (e.g., virtual avatar, full-body illusion) or merely a body part (e.g., rubber hand, prosthesis,
Ownership and disownership
Although the sense of body ownership may appear as a given, various pathological conditions reveal the possibility of feeling disownership towards one’s body (see Table 2). For example, patients suffering from the psychiatric disorder of depersonalization experience a general alteration of their relation to the self, such that they often feel as if their body did not belong to them or as if it had disappeared, leading them to compulsively touch their body and pour hot water on it to reassure
Conclusion
This paper did no deliver the key to the sense of ownership. Rather, it did the spadework to clarify the conceptual landscape of ownership, embodiment and disownership. In particular, I highlighted the conceptual knots that need to be untied before building up any theory of ownership. I addressed issues such as the functional role and the dynamics of embodiment, degrees and measures of ownership, shared body representation between self and others, and disownership delusions. I proposed that an
Acknowledgment
This work was supported by an ANR Grant 07-1-191653.
References (79)
- et al.
Keeping in touch with one’s self: Multisensory mechanisms of self-consciousness
PLoS ONE
(2009) - et al.
Narrators and comparators: The architecture of agentive self-awareness
Synthese
(2007) - Bermudez, J.L. (in press). Bodily awareness and self-consciousness. In S. Gallagher (Ed.), Oxford handbook of the self....
- et al.
Remission of somatoparaphrenic delusion through vestibular stimulation
Neuropsychologia
(1991) - et al.
Full-body illusions and minimal phenomenal selfhood
Trends in Cognitive Sciences
(2009) Neuroscience probing the neural basis of body ownership
Science
(2004)- et al.
Rubber hands ‘feel’ touch that eyes see
Nature
(1998) - et al.
Apotemnophilia: A neurological disorder
NeuroReport
(2008) Erewhon
(1872)- et al.
Peripersonal space and body schema: Two labels for the same concept?
Brain Topography
(2009)
Tool-use induces morphological updating of the body schema
Current Biology
Pride and a daily marathon
Exploratory findings with virtual reality for phantom limb pain; from stump motion to agency and analgesia
Disability and Rehabilitation
On the immunity principle: A view from a robot
Trends in Cognitive Sciences
Defensive movements evoked by air puff in monkeys
Journal of Neurophysiology
Body-extension versus body incorporation: Is there a need for a body-model?
Phenomenology and the Cognitive Sciences
Habeas Corpus: The sense of ownership of one’s own body
Mind and Language
Body schema and body image-pros and cons
Neuropsychologia
Widening the body to rubber hands and tools: What’s the difference?
Revue de Neuropsychologie, Neurosciences Cognitives et Cliniques
Functional results of the first human double-hand transplantation
Annals of Surgery
Rubber hands feel the touch of light
Psychological Science
The experimental induction of out-of-body experiences
Science
How many arms make a pair? Perceptual illusion of having an additional limb
Perception
Threatening a rubber hand that you feel is yours elicits a cortical anxiety response
Proceedings of the National Academy of Sciences of the United States of America
Dynamic size-change of hand peripersonal space following tool use
NeuroReport
Face or hand, not both: Perceptual correlates of reafferentation in a former amputee
Current Biology
From axons to identity: Neurological explorations of the nature of the self
Right hemisphere pathology and the self: Delusional misidentification and reduplication
Desire for amputation of a limb: paraphilia, psychosis, or a new type of identity disorder
Psychological Medicine
Losing one’s hand: Visual-proprioceptive conflict affects touch perception
PLoS ONE
The role of motor intention in motor awareness: An experimental study on anosognosia for hemiplegia
Brain
How the body shapes the mind
Illusory movements of the paralyzed limb restore motor cortex activity
Neuroimage
Cortical reorganization in motor cortex after graft of both hands
Nature Neuroscience
Reaching with alien limbs: Visual exposure to prosthetic hands in a mirror biases proprioception without accompanying illusions of ownership
Perception & Psychophysics
The selective effect of the image of a hand on visuotactile interactions as assessed by performance on the crossmodal congruency task
Experimental Brain Research
The rubber hand illusion in action
Neuropsychologia
How many motoric body representations can we grasp?
Experimental Brain Research
Cited by (307)
Does the avatar embodiment moderate the Proteus effect?
2024, International Journal of Human Computer StudiesSkin temperature changes in response to body ownership modulation vary according to the side of stimulation
2023, Physiology and BehaviorNeural encoding of artificial sensations evoked by peripheral nerve stimulation for neuroprosthetic applications
2023, Artificial Intelligence in Tissue and Organ Regeneration
- ☆
This article is part of a special issue of this journal on Brain and Self: Bridging the Gap.