Intermuscular Coherence as a Biomarker for ALS

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease caused by neuronal death in the motor system, both in the brain and spinal cord. It results in progressive weakness throughout the body, and typically leads to respiratory failure 3-5 years after symptom onset. Therapy initiation and drug development are hindered, in part, by the lack of objective disease markers. This is a multi-center trial to validate a potential biomarker for ALS, known as intermuscular coherence (IMC-βγ). IMC measures the correlation in the activity of two muscles during a simple motor task. In a preliminary study we found that patients with ALS have lower IMC than do control subjects. Because measuring IMC is quick, non-invasive, painless, and only requires equipment readily available in standard clinical neurophysiology labs, if validated it would be an important biomarker for ALS.