title: Vestibular receptors contribute to cortical auditory evoked potentials.
abstract: Acoustic sensitivity of the vestibular apparatus is well-established, but the contribution of vestibular receptors to the late auditory evoked potentials of cortical origin is unknown. Evoked potentials from 500 Hz tone pips were recorded using 70 channel EEG at several intensities below and above the vestibular acoustic threshold, as determined by vestibular evoked myogenic potentials (VEMPs). In healthy subjects both auditory mid- and long-latency auditory evoked potentials (AEPs), consisting of Na, Pa, N1 and P2 waves, were observed in the sub-threshold conditions. However, in passing through the vestibular threshold, systematic changes were observed in the morphology of the potentials and in the intensity dependence of their amplitude and latency. These changes were absent in a patient without functioning vestibular receptors. In particular, for the healthy subjects there was a fronto-central negativity, which appeared at about 42 ms, referred to as an N42, prior to the AEP N1. Source analysis of both the N42 and N1 indicated involvement of cingulate cortex, as well as bilateral superior temporal cortex. Our findings are best explained by vestibular receptors contributing to what were hitherto considered as purely auditory evoked potentials and in addition tentatively identify a new component that appears to be primarily of vestibular origin.
authors: The University of Manchester, UK. Electronic address: neil.todd@manchester.ac.uk.
authors: Neil P M
authors: NP
authors: Todd
authors: The University of Manchester, UK.
authors: Aurore C
authors: AC
authors: Paillard
authors: The University of Manchester, UK.
authors: Karolina
authors: K
authors: Kluk
authors: The University of Manchester, UK.
authors: Elizabeth
authors: E
authors: Whittle
authors: University of New South Wales, Australia.
authors: James G
authors: JG
authors: Colebatch
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D001301:Audiometry, Pure-Tone; D001303:Auditory Cortex / Q000502:physiology*; D001306:Auditory Pathways / Q000502:physiology; D001309:Auditory Threshold; D004569:Electroencephalography; D005072:Evoked Potentials, Auditory; D005260:Female; D006179:Gyrus Cinguli / Q000502:physiology*; D006801:Humans; D008297:Male; D011571:Psychoacoustics; D011930:Reaction Time; D011984:Sensory Receptor Cells / Q000502:physiology*; D013997:Time Factors; D058585:Vestibular Evoked Myogenic Potentials; D014722:Vestibule, Labyrinth / Q000502:physiology*; D055815:Young Adult