In man the perioral reflexes evoked by tapping of the face have been investigated electromyographically and clinically in normal and pathological conditions. The following reflexes were noted: A unilateral reflex in the mentalis and perioral muscles with a short latency and many features in common with myotatic reflexes; a bilateral reflex with a long latency (25-40 msec.) in the mentalis and perioral muscles; and a reflex contraction of the mentalis muscles associated with a strong blink reflex. All these reflexes are normal reflexes but very lively reflexes are more common in cases of parkinsonism and amyotrophic lateral sclerosis.