IlloM study: Illusions of limb movements
Research type
Research Study
Full title
Investigation of movement illusions induced by cutaneous vibrations in people with upper limb absence
IRAS ID
293334
Contact name
Peter Kyberd
Contact email
Sponsor organisation
University of Portsmouth
Duration of Study in the UK
0 years, 11 months, 31 days
Research summary
Persons who have lost entirely or partially a limb may wish to restore its function and start using an external device, a prosthesis. To a certain level it is possible to replace the mechanical functions with a gadget but it is not yet possible to have any feelings in this man-made limb. The users must watch their artificial hand, arm or leg in order to see if it does what it should.
We have the ability to know where our body parts are even if we do not watch them. This sense is called proprioception and it is the reason why we are able to touch our nose tip with our eyes closed. We are using this feeling unknowingly and it helps us to move smoothly and accurately. People who are using an artificial limb to replace the functions of a lost body part do not know where their gadget is or what it is doing without watching it.
It was discovered 50 years ago that it is possible to have the feeling of a moving limb even when this limb stays stationary. When muscles get vibrated under the right conditions, the illusion can be created that the connected joint is moving. For example, when the muscles in the upper arm are vibrated, the person could feel that their elbow is moving. In reality, the elbow does not move but the brain thinks it does.
Until now, research focused on able-bodied people to investigate this phenomenon. It is not clear how the experience of people with limb deficiencies differ. Moreover it is not known at all how the experiences differ between people who have congenital limb deficiencies and those who had an amputation. The results of this study may show a new method of non-invasive sensory feedback for prosthetic limbs.
REC name
London - Camden & Kings Cross Research Ethics Committee
REC reference
21/PR/1420
Date of REC Opinion
12 Nov 2021
REC opinion
Further Information Favourable Opinion