Effects of vestibular nerve section on sound-evoked myogenic potentials in the sternocleidomastoid muscle of monkeys

Objective The aim of this study was to elucidate the neural pathway for sound-evoked myogenic potentials (SEMPs) in monkeys with characteristics similar to those of vestibular evoked myogenic potentials in humans. Methods Six macaque monkeys were examined. The effects of total and selective vestibular nerve section on the SEMPs were evaluated in three monkeys. Results After total vestibular nerve section, the SEMPs and caloric nystagmus were eliminated, and the auditory brainstem response remained. After selective superior vestibular nerve section, the SEMPs remained, but caloric nystagmus was eliminated. Conclusions The inferior vestibular nerve comprises a neural pathway for SEMPs in monkeys. Significance SEMP in monkeys may provide a model of human VEMPs.