Reduction of hemifacial spasm and dysarthria following EMG biofeedback.

In this case study, a geriatric patient who had an 18-year history of hemifacial spasm was given EMG-biofeedback-assisted relaxation training. No formal speech therapy was provided. Our results confirmed two hypotheses: (a) The patient would learn to reduce frontalis EMG and facial spasm with and then without biofeedback, and (b) as a result, speech would be markedly improved. At both the 1-month and 15-month follow-up the patient retained the ability to relax his facial muscles with similar carry-over to speech. Possible neurophysiologic mechanisms of action mediating the feedback training are discussed.