Woman's missing digits grow back in phantom form

A woman born missing a finger and a thumb has grown them back ? albeit as part of a phantom limb. This extraordinary occurrence shows that our brain contains a fully functional map of our body image, regardless of what our limbs actually look like.

The woman, RN, was born with just three fingers on her right hand. Aged 18, RN had the hand amputated after a car accident. She later began to feel that her missing limb was still present, and developed a "phantom" hand.

"But here's the interesting thing," says Paul McGeoch at the University of California, San Diego. "Her phantom hand didn't have three digits, it had five."

RN was aware of a full complement of fingers, but her phantom thumb and index finger were less than half the usual length.

With training using a mirror box trick ? a tool that creates the visual illusion of two hands ? McGeoch and V.S Ramachandran, also at San Diego, managed to extend her short phantom finger and thumb to normal length.

McGeoch says this study indicates that there is a hardwired representation in the brain of what the body should look like, regardless of how it actually appears in real life. It shows us more about the balance between the external and innate representations of a limb, he says.

"The presence of the deformed hand was suppressing the brain's innate representation of her fingers which is why they appeared shorter, but after the hand was removed and the inhibition taken away, the innate representation kicks in again."

Matthew Longo at Birkbeck, University of London, says it is a fascinating case study. "It contributes to a growing literature suggesting that our conscious experience of our body is, at least in part, dependent on the intrinsic organisation of the brain, rather than a result of experience."

Journal reference: Neurocase, DOI: 10.1080/13554794.2011.556128

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.

Have your say

Only subscribers may leave comments on this article. Please log in.

Only personal subscribers may leave comments on this article

Subscribe now to comment.

All comments should respect the New Scientist House Rules. If you think a particular comment breaks these rules then please use the "Report" link in that comment to report it to us.

If you are having a technical problem posting a comment, please contact technical support.

Source: http://feeds.newscientist.com/c/749/f/10897/s/223fd495/l/0L0Snewscientist0N0Carticle0Cdn221580Ewomans0Emissing0Edigits0Egrow0Eback0Ein0Ephantom0Eform0Bhtml0DDCMP0FOTC0Erss0Gnsref0Fonline0Enews/story01.htm

new hampshire primary hue jackson alabama football coachella 2012 line up lsu crimson tide crimson tide