Dr Neil Todd
Department of Psychology, University of Exeter, UK.
Note: This is the second presentation in a two part series-
Title of Presentation: "Recent developments in non-invasive human cerebellar electrophysiology II: Cerebellar evoked potentials (CEPs)".
Overview: The cerebellum receives strong afferent input, somatosensory, auditory, visual and vestibular and high amplitude evoked responses can be recorded from its surface in response to afferent stimulation (Eccles et al. 1968). Despite this, there is no present method of recording evoked cerebellar potentials (CEPs) in intact human subjects non-invasively. Over the last decade or so, we have investigated central vestibular projections using the same acoustic and inertial activations of the vestibular end-organs which produce vestibular evoked myogenic potentials (VEMPs) using multiple electrodes and applying source analysis methods (Todd et al 2008, 2014, 2016). Most recently we provided further evidence that short latency responses of likely cerebellar origin co-occur with the VEMPs (Todd et al 2017). In this presentation I will described some recent experiments in which we recorded short latency CEPs during visual-vestibular and audio-motor stimulation with electrodes placed over the posterior fossa close to the standard 10-20 CB location. In most subjects CEPs co-occur with the electrocerebellogram (ECeG) and are modulated by the same stimuli. It is suggested that this methodology may have value both for understanding normal cerebellar function and its role in disease (Todd et al. in prep, b).
Eccles JC, Provini L, Strata P, Taborikova H (1968) Analysis of electrical potentials evoked in the cerebellar anterior lobe by stimulation of hindlimb and forelimb nerves. Exp Brain Res 6, 171-194.
Todd, NPM, Rosengren, SM. and Colebatch JC (2008) A source analysis of vestibular evoked potentials (VsEPs) produced by air- and bone-conducted sound. Clinical Neurophysiology 119, 1881-1894.
NPM Todd, AC Paillard, K Kluk, E Whittle, JG Colebatch (2014) Source analysis of short and long latency vestibular-evoked potentials (VsEPs) produced by left versus right ear air-conducted 500 Hz tone pips. Hearing Research 312, 91 – 102.
Todd NPM, Govender S, Colebatch JG (2016) Vestibular-dependent inter-stimulus interval effects on sound evoked potentials of central origin. Hearing Research 341, 190-201
Todd NPM, Govender S, Colebatch JG (2017). The inion response revisited: evidence for a possible cerebellar contribution to vestibular-evoked potentials produced by air-conducted sound stimulation. J Neurophysiol. 117, 1000 – 1013.
Todd NPM, Govender S, Colebatch JG (in preparation, b). Optokinetic modulation of human vestibular cerebellar evoked potentials (VCEPs).
Details:The presentation will be held in Bldg 3.G.55, Bankstown campus.
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