caa a22 4500 44535187X CHVBK 20180317142846.0 cr unu---uuuuu 170323e20110601xx s 000 0 eng 10.1007/s00221-011-2681-4 doi (NATIONALLICENCE)springer-10.1007/s00221-011-2681-4 Direction-dependent excitatory and inhibitory ocular vestibular-evoked myogenic potentials (oVEMPs) produced by oppositely directed accelerations along the midsagittal axis of the head [Elektronische Daten] [Peter Jombik, Pavel Spodniak, Vladimír Bahyl] Oppositely directed displacements of the head need oppositely directed vestibulo-ocular reflexes (VOR), i.e. compensatory responses. Ocular vestibular-evoked myogenic potentials (oVEMPs) mainly reflect the synchronous extraocular muscle activity involved in the process of generating the VOR. The oVEMPs recorded beneath the eyes when looking up represent electro-myographic responses mainly of the inferior oblique muscle. We aimed: (1) to study the properties of these responses as they were produced by head acceleration impulses to the forehead and to the back of the head; (2) to investigate the relationships between these responses and the 3-D linear head accelerations that might reflect the true stimulus that acts on the vestibular hair cells. We produced backward- and forward-directed acceleration stimuli in four conditions (positive and negative head acceleration impulses to the hairline and to the inion) in 16 normal subjects. The oVEMPs produced by backward- and forward-directed accelerations of the head showed consistent differences. They were opposite in the phase. The responses produced by backward accelerations of the head began with an initial negativity, n11; conversely, those produced by accelerations directed forward showed initially a positive response, p11. There was a high inter-subject correlation of head accelerations along the head anteroposterior and transverse axes, but almost no correlation of accelerations along the vertical axis of the head. We concluded that backward-directed head accelerations produced an initial excitatory response, and forward-directed accelerations of the head were accompanied by an initial inhibitory response. These responses showed dependence on acceleration direction in the horizontal plane of the head. This could be consistent with activation of the utricle. The Author(s), 2011 Vestibulo-ocular reflex nationallicence Otolith nationallicence Utricle nationallicence Vestibular-evoked potentials nationallicence Head acceleration nationallicence Jombik Peter Department of Neurology, Laboratory of Clinical Neurophysiology, Zvolen Hospital, 960 01, Zvolen, Slovak Republic aut Spodniak Pavel Department of Environmental Sciences, Faculty of Environmental Technology, Zvolen Technical University, Zvolen, Slovak Republic aut Bahyl Vladimír Department of Physics, Electrotechnics and Applied Mechanics, Faculty of Wood Sciences, Zvolen Technical University, Zvolen, Slovak Republic aut Experimental Brain Research Springer-Verlag 211/2(2011-06-01), 251-263 0014-4819 211:2<251 2011 211 221 https://doi.org/10.1007/s00221-011-2681-4 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00221-011-2681-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Jombik Peter Department of Neurology, Laboratory of Clinical Neurophysiology, Zvolen Hospital, 960 01, Zvolen, Slovak Republic aut NATIONALLICENCE 700 1- Spodniak Pavel Department of Environmental Sciences, Faculty of Environmental Technology, Zvolen Technical University, Zvolen, Slovak Republic aut NATIONALLICENCE 700 1- Bahyl Vladimír Department of Physics, Electrotechnics and Applied Mechanics, Faculty of Wood Sciences, Zvolen Technical University, Zvolen, Slovak Republic aut NATIONALLICENCE 773 0- Experimental Brain Research Springer-Verlag 211/2(2011-06-01), 251-263 0014-4819 211:2<251 2011 211 221 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer