RT Journal Article
SR Electronic
T1 Reorganization of Motor and Somatosensory Cortex in Upper Extremity Amputees with Phantom Limb Pain
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 3609
OP 3618
DO 10.1523/JNEUROSCI.21-10-03609.2001
VO 21
IS 10
A1 Anke Karl
A1 Niels Birbaumer
A1 Werner Lutzenberger
A1 Leonardo G. Cohen
A1 Herta Flor
YR 2001
UL http://www.jneurosci.org/content/21/10/3609.abstract
AB Phantom limb pain (PLP) in amputees is associated with reorganizational changes in the somatosensory system. To investigate the relationship between somatosensory and motor reorganization and phantom limb pain, we used focal transcranial magnetic stimulation (TMS) of the motor cortex and neuroelectric source imaging of the somatosensory cortex (SI) in patients with and without phantom limb pain. For transcranial magnetic stimulation, recordings were made bilaterally from the biceps brachii, zygomaticus, and depressor labii inferioris muscles. Neuroelectric source imaging of the EEG was obtained after somatosensory stimulation of the skin overlying face and hand. Patients with phantom limb pain had larger motor-evoked potentials from the biceps brachii, and the map of outputs was larger for muscles on the amputated side compared with the intact side. The optimal scalp positions for stimulation of the zygomaticus and depressor labii inferioris muscles were displaced significantly more medially (toward the missing hand representation) in patients with phantom limb pain only. Neuroelectric source imaging revealed a similar medial displacement of the dipole center for face stimulation in patients with phantom limb pain. There was a high correlation between the magnitude of the shift of the cortical representation of the mouth into the hand area in motor and somatosensory cortex and phantom limb pain. These results show enhanced plasticity in both the motor and somatosensory domains in amputees with phantom limb pain.