Recording click-evoked myogenic potentials (CEMPs) with a setup for brainstem auditory evoked potentials (BAEPs)

Area of Science:

• Neuroscience
• Otolaryngology
• Audiology

Background:

• Click-evoked myogenic potentials (CEMPs) are generated in the sternocleidomastoid (SCM) muscle via a reflex arc involving the sacculus and vestibular nerve.
• CEMPs are characterized by a P13-N20 complex.
• Standard brainstem auditory evoked potential (BAEP) filters may be suitable for detecting CEMPs.

Purpose of the Study:

• To investigate the feasibility of recording CEMPs using standard BAEP filters.
• To assess the utility of CEMPs for simultaneous evaluation of auditory and vestibular pathways.

Main Methods:

• Fifty healthy subjects participated in the study.
• Recordings were performed using conventional BAEP settings with a wide time window (100 ms) and unilateral auditory stimulation.
• CEMPs and BAEPs were simultaneously recorded from the earlobe and SCM muscles in both sitting and supine positions.

Main Results:

• The CEMP P13-N20 component was successfully identified in all subjects in the sitting position, but not in the supine position.
• CEMPs were detected at both the ipsilateral earlobe and SCM muscle.
• Earlobe CEMPs showed a 0.7 ms shorter latency than SCM CEMPs and exhibited similar stimulus intensity relationships.

Conclusions:

• The findings demonstrate that CEMPs can be recorded simultaneously with BAEPs, providing insights into both brainstem auditory function and vestibular reflexes.
• This technique offers a potential method for assessing the sacculus-vestibular nerve pathway.
• Further research in patients with vestibular nerve impairments is recommended to confirm clinical applicability.