Amputees Experience Prosthetic Hand As Their Own
From: Physical Therapy Products - 12/24/2008

Scientists have succeeded in inducing people with an amputated arm to
experience a prosthetic rubber hand as belonging to their own body. The
results can lead to the development of a new type of touch-sensitive
prosthetic hands. 

The illusion of having a rubber hand was achieved by the scientists at
Karolinska Institutet and Lund University in Sweden by touching the stump of
the amputated arm out of sight of the subject while simultaneously touching
the rubber hand in full view of the same subject. This created the illusion
that the sensory input was coming from the prosthetic hand rather than from
the stump, and that the hand belonged to the subject's own body. 

The effect was confirmed by the subjects' own descriptions of the experience
and by their tendency to point to the hand when asked to localize the point
of stimulation. That they experienced the rubber hand as their own was also
substantiated physiologically in that they started to sweat when the hand was
pricked with a needle. 

The study, which was carried out at the Red Cross hospital in
Stockholm, opens up new opportunities for developing prosthetic hands that
can be experienced by wearers as belonging to their own bodies, which would
be a great benefit to patients and which is considered an important objective
in applied neuroscience. 

"We'll now be looking into the possibilities of developing a prosthetic hand
that can register touch and stimulate the stump to which it's attached," says
Henrik Ehrsson, one of the researchers involved in the study. "If this makes
it possible to make a prosthetic sensitive by cheating the brain, it can
prove an important step towards better and more practical prosthetic hands
than those available today."  

The study is part of the EU's SmartHand project, which is administered from
Lund University. The objective of the SmartHand project is to develop a new
type of thought-controlled prosthetic hand with advanced motor and sensory
capabilities. Other financiers include the European Research Council, the
Swedish Research Council, and Skåne County Council. 

Read the article at:
http://www.ptproductsonline.com/SOAPNotes/2008-12-24_01.asp

Links:
Karolinska Institutet
http://www.ki.se/

Lund University
http://www.lu.se/lund-university

Links:
Red Corss Hospital in Stockholm
http://www.redcross.se

SmartHand
http://www-arts.sssup.it/newCyberhand/smarthand/index.htm

What is The SmartHand?
http://www.elmat.lth.se/~smarthand/index.html

SmartHand: Cyborg Limbs Will Feel Like User's Own
http://www.fastcompany.com/blog/kit-eaton/technomix/prosthetic-limbs-feel-users-own
http://www.medgadget.com/archives/2008/12/smarthand_thought_controlled_prosthesis_that_patients_feel.html

Upper limb amputees can be induced to experience a rubber hand as their own
http://brain.oxfordjournals.org/cgi/content/full/awn297v1

Amputees can experience prosthetic hand as their own
http://ki.se/ki/jsp/polopoly.jsp?d=130&a=66662&l=en&newsdep=130