Thresholds for vestibular-evoked myogenic potentials (VEMPs) produced by impulsive transmastoid acceleration

Abstract

Objective: To evaluate methods for estimating thresholds of vestibular evoked myogenic potentials (VEMPs) and ocular VEMPs (OVEMPs) produced by impulsive transmastoid acceleration (ITA). Design: VEMPs and OVEMPs were obtained simultaneously from subjects in supine posture with both head and eyes elevated. Thresholds to ITA were measured using four different response identification methods. Study sample: Twelve adult subjects with no history of auditory or vestibular deficits. Results: VEMP and OVEMP thresholds were found within the range of −8 to −26 dB re 0.2 g, with overall VEMP thresholds being lower than OVEMP thresholds by average of 3–10 dB, depending on the method used. Conclusion: VEMPs can be obtained at lower ITA stimulation levels than OVEMPs. Threshold values depend on the method used to define response presence.

Key Words::

• VEMP
• OVEMP
• threshold
• impulsive acceleration

Acknowledgements

This work was supported by a Wellcome Trust grant WT091961MA. These results have been presented as a poster during the 27th Barany Society Meeting (Uppsala, Sweden) on 10–13th June 2012. The authors would like to thank Prof. Colebatch (University of New South Wales, Australia) for helpful discussions concerning methodology for measuring gamma thresholds.

Declaration of interest: There is no conflict of interest in the manuscript.