Bodily Self-attribution Caused by Seeing External Body-Resembling Objects and the Control of Grasp Forces.

The brain localizes body parts in their perceived visual locations. The brain can, however, be easily fooled. By making use of the Rubber Hand Illusion (RHI), a feeling of ownership of the rubber hand can be evoked. The influence of this illusion on grasp force has not yet been researched, but it might well prove promising for grasp control during tool usage. This study explores whether the RHI can be used to give a person better control over grasp force when manipulating an instrument that makes use of the RHI than when using an instrument that does not. Ten participants performed grasp and pull tasks under three different conditions. They were required to grasp an object with their bare hands, with a rubber-hand, and with an instrument. After analyzing grasp forces during maximal pulling loads (4.95 N barehanded, 6.45 N rubber-handed and 7.9 N using an instrument), it may be concluded that the RHI can contribute to improved grasp control. [ABSTRACT FROM AUTHOR]