Recent research has suggested that the sensation of having a phantom limb affects more people than had previously been thought.
Published in Cortex, the study found that people whose nervous system had been damaged - often through a stroke - often feel that their leg or arm is in a completely different position.
On other occasions patients sensed that it was moving when it was still.
Dr Daniel Antoniello from the Albert Einstein College of Medicine in New York commented: "The study sheds light on how the phenomenal experience of one's body can be altered after neurological damage.
"Remarkably, some of these individuals are able to control their phantom limbs with near total volition."
He added that the group of patients identified by the report can provide "provide a valuable opportunity to explore how the brain constructs the conscious perception of the body".
The condition had previously been thought to affect mostly those who had been subject to an amputation.
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