Phantom Sensations in a Patient with Cervical Nerve Root Avulsion

Abstract

This case study reports detailed phantom sensations in a 35-yr.-old man who had his C5 and C6 cervical nerve roots avulsed from the cord during a motorcycle accident at the age of 22 years. The subject, who was left with a paralyzed right deltoid muscle, anesthetic sensation along the upper lateral portion of the right arm, and absent right biceps reflex, became aware of phantom right arm and hand sensations a few months after the original injury. This finding--which has important implications for understanding the process involved in bodily perception as well as the development of these perceptions--provides evidence of a distributed neural representation of the body that has both genetic and experiential determinants. The implications of these findings are discussed with reference to recent concepts of phantom limb experiences and related phenomena.

Weight-Discrimination Sensitivity in Congenitally Blind and Sighted Adults

“…One thing that follows from the multiple changes in the brain accompanying plasticity is that plasticity can be inferred from many things, including the effects of blindness on the acuity of the senses other than vision. This conceptualization fits nicely with research on phantom limbs (Grouios, 1996a(Grouios, , 1996b(Grouios, , 1998a(Grouios, , 1998b(Grouios, , 1999a(Grouios, , 1999bMelzack, 1990Melzack, , 1992Melzack, , 1995, which has found that the central nervous system demonstrates a lifelong capacity to change its functional organization in response to altered input and output conditions (Birbaumer et aI., 1997;Davis et aI., 1998;Elbert et aI., 1994;Flor et aI., 1995;Flor et aI., 1998;Kaas, 1998;Kew et aI., 1997;Knecht et aI., 1998;Ramachandran, 1993). It is also in line with limited observations on phantom seeing (R. Cohn, 1971;Pankow & Luchins, 1997;Schultz & Melzack, 1991), phantom hearing (Mohlnickel, Elbert, Taub, & Flor, 1998;Wang, Vannier, Skinner, Cavalcanti, & Harding, 1998),phantom tasting (Whitehead, McGlathery, & Manion, 1995), and phantom smelling (Grouios, submitted for publication), which have suggested that these referred phantom sensations are related to plastic alterations in the sensory areas of the cerebral cortex in response to the loss of afferent inputs from sensory receptors because of damage to or impairment of the nervous system.…”