Pain
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This paper reviews reports of phantom limb sensations which resemble somatosensory events experienced in the limb before amputation. It also presents descriptions of this phenomenon in 68 amputees who took part in a series of clinical studies. These somatosensory memories are predominantly replicas of distressing pre-amputation lesions and pains which were experienced at or near the time of amputation, and are described as having the same qualities of sensation as the pre-amputation pain. ⋯ The experience of somatosensory memories does not appear to be related to the duration of pre-amputation pain, time since amputation, age, gender, prosthetic use, level of amputation, number of limbs amputated, or whether the amputation followed an accident or illness. The results suggest that somatosensory inputs of sufficient intensity and duration can produce lasting changes in central neural structures which combine with cognitive-evaluative memories of the pre-amputation pain to give rise to the unified experience of a past pain referred to the phantom limb. Implications for pre- and post-operative pain control are discussed.