Brain can adapt to treat prostheses like body part
medwireNews: Research findings suggest that the human brain can learn to treat prosthetic devices as part of the body.
Among a group of 55 wheelchair-bound individuals with a history of spinal cord injury, 67% reported that they felt their wheelchair was part of their body and 72% included the wheelchair in descriptions of their body image.
And among all patients, regular wheelchair use "induced the perception that the body's edges are not fixed, but are instead plastic and flexible to include the wheelchair," write the authors in the open-access journal PLoS ONE.
The embodiment of a wheelchair displayed by patients in the current study may "offer an initial step towards the determination of clearly dissociable subcomponents of prosthetic device embodiment," say Mariella Pazzaglia (Sapienza University of Rome, Italy) and co-authors.
However, they warn that the current findings "cannot be generalized to all occurrences of corporeal awareness of a tool."
The results arise from the analysis of questionnaire-based reports of patients' introspective experiences of using a wheelchair.
According to the authors, the patients' answers suggest that multiple factors contribute to the mechanism via which a person incorporates an external tool into his or her body image.
These factors include a feeling of ownership over the tool, an established sense of control of the body and how it moves, and multisensory integration and regulation of sensory and motor information flow.
Among the study group, time since spinal cord injury and patient experience with using a wheelchair did not appear to influence perception of the wheelchair as a body part.
But, a stronger perception of the wheelchair as a body part was exhibited by patients with lower spinal cord injuries and loss of movement and sensation in the legs and unaffected upper body movement compared with those with upper spinal cord injury and whole-body impairment.
Pazzaglia et al imply that the observed phenomenon of "embodying" a wheelchair may increase how effectively a patient uses his or her wheelchair.
"This ease of use may lead to greater autonomy and self-organization, thus allowing patients to benefit from the opportunities offered by the environment in which they move," conclude the authors.
By Lauretta Ihonor, medwireNews Reporter