The ability to feel sensations and pain in a limb or limbs that no longer exist. Phantom limb syndrome experienced by amputees is generally characterized by nonpainful sensations, such as the perception of movement and reception of external stimuli (e.g., touch, pressure, itch), and by painful sensations, such as the perception of burning, tingling, or shooting pains. The syndrome can be explained by map expansion neuroplasticity, in which the local brain region that once specialized in controlling the function of the amputated limb and that is reflected as a discrete “map” in the cerebral cortex of the brain is taken over by an adjacent brain map such as the face map, thereby expanding the face map. The acquisition of a part of the unused phantom map by the face map results in the perception of sensation in the amputated limb when the face is touched. Treatment of the syndrome may employ pain-relieving medications, coping techniques, nonsurgical treatments (including shock therapy and acupuncture), and implantable treatments, such as deep brain stimulation and spinal cord stimulation. Mirror box therapy has been successful in a small number of patients, primarily those who experienced paralysis of a limb prior to amputation and thus suffer from a condition known as “learned paralysis.”

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