Cognitive experiment on a patient with phantom pain in a paralysed arm. Many patients with amputated or paralysed limbs feel 'phantom' sensations or pain, as though the limb were still functioning. In this experiment on a patient with a paralysed arm, a video is made of a mirror image of the healthy arm (shown here), and projected to the patient. The image generates an illusion for the patient that they are watching their paralysed arm perform a variety of tasks. This stimulates the same areas of the brain as would be involved in actually performing those movements with the paralysed arm. This alleviates phantom pain. For images of this experiment see M873/072-M873/074.