Giandomenico Iannetti at University College London and colleagues gave 20 volunteers a series of painful "jabs" to the back of one of their hands using a laser, with each pulse lasting 8 to 12 seconds. In half of the experiments the group received the jabs while they laid their palms face down on a desk. In the other half they crossed their arms over one another on the desk. Volunteers rated the pain they felt on a scale from zero to 100.
Volunteers with crossed hands rated three increasing pain intensities as less painful compared with when they kept their hands uncrossed.
Iannetti suggests that placing your hands in unfamiliar spatial positions relative to the body muddles the brain and disrupts the processing of the pain message. "You get this mismatch between your body's frame of reference and your external space frame of reference," he says. Similar pain-relieving effects have been reported before using illusions involving mirrors and virtual limbs.
Read more at New Scientist
No comments:
Post a Comment