Read the text below and answer the following
question based on it.
Virtual reality may help relieve phantom limb pain.
In a recent study, patients experienced reduced phantom
limb pain after playing an augmented reality car racing
game that required them to move the missing limb. Phantom
limb pain is the experience of pain in a limb after it has been
amputated.
The underlying mechanisms responsible for phantom limb
pain remain unclear. However, it appears that it may arise
as a consequence of abnormal neural circuitry in central
areas of the brain.
Limited success has been achieved with mirror therapy in
which reflections of the unaffected limb can be used to
create the illusion that the amputated limb is moving.
The latest study has taken the mirror therapy concept a step
further; patients visualise and 'move' the phantom limb using
augmented reality—‘phantom motor execution’. It was
conducted in 14 patients who had been experiencing
phantom limb pain since the amputation of an arm.
Sensors that could detect muscular activity were attached to
the stump of the missing arm. The signals received by these
sensors were then used to produce an image of an active
arm on a computer screen.
Patients were trained to use these signals to control the
virtual arm, drive a virtual race car around a track and to
copy the movements of an arm on screen with their
phantom movements. After twelve 2-hour treatment
sessions, the patients underwent follow-up interviews 1, 3
and 6 months later.
Based on the patients' ratings, the intensity, quality, and
frequency of pain had reduced by 50% after the treatment.
At the start of the study, 12 patients reported feeling
constant pain whereas only 6 did 6months after the
treatment. However, one patient thought that there was not
a considerable difference in the levels of phantom pain
before and after treatment.