Federica M Raciti, Yasniary Morales, Hillary A Snapp, Suhrud M Rajguru
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引用次数: 0
Abstract
Introduction: Cervical vestibular evoked myogenic potentials (cVEMPs) provide an objective measure of the integrity of the sacculo-collic pathway leading to their widespread use as a clinical tool in the diagnostic vestibular test battery. Though the application of cVEMPs in preclinical models to assess vestibular function, as performed in relevant clinical populations, remains limited. The present study aimed to establish a rodent model of cVEMP with standardized methods and protocols, examine the neural basis of the responses, and characterize and validate important features for interpretation and assessment of vestibular function.
Methods: We compared air-conducted sound (ACS)-evoked VEMPs from the sternocleidomastoid muscles in naïve Brown Norway rats. A custom setup facilitated repeatable and reliable measurements which were carried out at multiple intensities with ACS between 1 and 16 kHz and over 7 days. The myogenic potentials were identified by the presence of a positive (P1)-negative (N1) waveform at 3-5 ms from the stimulus onset. Threshold, amplitude, and latency were compared with intensity- and frequency-matched responses within and between animals.
Results: cVEMP responses were repeatedly evoked with stimulus intensities between 50-100 dB SPL with excellent test-retest reliability and across multiple measurements over 7 days for all frequencies tested. Suprathreshold, cVEMP responses at 90 dB SPL for 6-10 kHz stimuli demonstrated significantly larger amplitudes (p < 0.01) and shorter latencies (p < 0.001) compared to cVEMP responses for 1-4 kHz stimuli. Latency of cVEMP showed sex-dependent variability, but no significant differences in threshold or amplitude between males and females was observed.
Discussion: The results provide a replicable and reliable setup, test protocol, and comprehensive characterization of cVEMP responses in a preclinical model which can be used in future studies to elucidate pathophysiological characteristics of vestibular dysfunctions or test efficacy of therapeutics.
期刊介绍:
Frontiers in Integrative Neuroscience publishes rigorously peer-reviewed research that synthesizes multiple facets of brain structure and function, to better understand how multiple diverse functions are integrated to produce complex behaviors. Led by an outstanding Editorial Board of international experts, this multidisciplinary open-access journal is at the forefront of disseminating and communicating scientific knowledge and impactful discoveries to researchers, academics, clinicians and the public worldwide.
Our goal is to publish research related to furthering the understanding of the integrative mechanisms underlying brain functioning across one or more interacting levels of neural organization. In most real life experiences, sensory inputs from several modalities converge and interact in a manner that influences perception and actions generating purposeful and social behaviors. The journal is therefore focused on the primary questions of how multiple sensory, cognitive and emotional processes merge to produce coordinated complex behavior. It is questions such as this that cannot be answered at a single level – an ion channel, a neuron or a synapse – that we wish to focus on. In Frontiers in Integrative Neuroscience we welcome in vitro or in vivo investigations across the molecular, cellular, and systems and behavioral level. Research in any species and at any stage of development and aging that are focused at understanding integration mechanisms underlying emergent properties of the brain and behavior are welcome.