Research Reports - Corticomotor facilitation in vegetative state
Arch Phys Med Rehabil. 2013 Aug;94(8):1599-606
Pistoia F, Sacco S, Carolei A, Sarà M
OBJECTIVE: To investigate whether corticomotor facilitation induced by
transcranial magnetic stimulation (TMS-CF) could evoke a simple purposeful motor
behavior in patients with a diagnosis of vegetative state.
DESIGN: Cross-sectional survey.
SETTING: Post-coma and rehabilitation care unit.
PARTICIPANTS: Patients (N=6) with a diagnosis of vegetative state.
INTERVENTIONS: A cascade of consecutive motor-evoked potentials (MEPs) was
elicited under 3 different conditions: in the first condition, patients were at
rest (Rest); in the second, they were asked to open and close the right hand
(Execution); in the third, the examiner modeled a movement of abduction of the
thumb in front of the patient who was encouraged in advance to imitate the action
(Observation to Imitate).
MAIN OUTCOME MEASURES: Changes in MEP values from the abductor pollicis brevis
muscle and improvement in scores on the Coma Recovery Scale-Revised.
RESULTS: TMS-CF alone or combined with verbal instructions did not yield any
change; only the combination with imitation caused changes in MEPs (shorter
latency and increased amplitude) associated with behavioral improvement in 4
CONCLUSIONS: Encouraging observation to imitate may favor the transformation of
some perceived actions into motor images and performances, probably depending on
the activation of mirror motor neurons. In our opinion, combining visual input
with TMS-CF might have reinforced the coupling between movement planning and
execution, promoting the recovery of elementary motor activities in some
patients. The proposed protocol may contribute to unmasking signs of preserved
consciousness in patients with latent capacities for recovery.