"To elude dangerous objects in the environment and the collisions that may occur during wheelchair use, the brain needs to encode an internal representation of the body that includes the wheelchair," she said.
"Moreover, the simple action of picking objects up from the floor without tipping out of the wheelchair implies a change in the representation of the body to enable this to happen successfully and without the risk of possible damage to the individual due to a fall," she added. "All daily activities become an automatic way of thinking, not merely a mechanical or practical process."
Automatic thinking -- based on body maps that encompass inanimate objects -- plays plenty of other roles in people's lives, Georgetown's Dromerick said. For example, people who can wield a hammer effectively or parallel park with ease have learned to treat hammers and cars as extensions of themselves, he said.
The study appeared March 6 in the journal PLoS One.
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SOURCES: Mariella Pazzaglia, Ph.D., assistant professor, Sapienza University of Rome, Italy; Alexander Dromerick, M.D., vice president for research, National Rehabilitation Hospital, and chief of rehabilitation medicine, Georgetown University Medical Center, Washington D.C.; March 6, 2013, PLoS One
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