Amplitude-modulated-cVEMP: A novel method to assess vestibular functioning in aging population
Faculty Advisor Name
Dr. Erin G. Piker
Department
Department of Communication Sciences and Disorders
Description
The aging population is one of the pressing health concerns today. A major concern with increasing age is risk of falls, as falls are one of the leading causes of injury and death in older adults with an associated large economic cost. Vestibular system (ear related balance functioning) is an independent risk factor for falls among older adults. The primary role of the vestibular system is to maintain head and eye coordination, upright posture and balance, and conscious realization of spatial orientation and motion. The field of hearing and vestibular (ear related balance functioning) science has shown tremendous advancement in the last 30 years, however, our ability to diagnose and treat vestibular impairment is limited. Limitation in the assessment of vestibular system leaves 20-30% of patients with vestibular complaints undiagnosed. Thus, there is a need to develop techniques to study vestibular mechanisms that cannot be tapped using existing methods.
Our study is an attempt to explore a novel aspect of vestibular functioning that cannot be done using existing assessment techniques. Our study utilized a novel stimulation (amplitude modulated tones) and recording paradigm: amplitude-modulated-cVEMP (AMcVEMP) to characterize untapped mechanisms (phase synchrony of vestibular nerve and non-linearity of vestibular system) of the vestibular functioning. We aimed to study the effects of age on the phase synchrony and the non-linearity of the vestibular system using AMcVEMP. We included 73 human participants from three different age groups (young = 30 participants, middle age = 22 participants, older adults = 21 participants) to understand effects of age on the phase synchrony and non-linearity of the vestibular system.
Our data showed evidence of phase synchrony and non-linearity in the human vestibular system of all age groups. Our study also showed alteration in phase synchrony and non-linearity of vestibular system as an effect of aging. Phase synchrony of vestibular nerve and nonlinear processing in the vestibular system has been reported in many animal models, but there was no non-invasive method to assess this mechanism in human vestibular system. AMcVEMP is the only non-invasive tool to assess these mechanisms from human vestibular system. Ability to record phase synchrony and non-linearity from vestibular system can advance our understanding of the mechanisms of vestibular functioning in healthy and vestibular malfunctioning in disordered populations. Overall, the outcomes from the study have improved our understanding of age-related changes in the vestibular system and has opened areas for exploration that will eventually lead to better standard of care for older adults and patients with dizziness.
Amplitude-modulated-cVEMP: A novel method to assess vestibular functioning in aging population
The aging population is one of the pressing health concerns today. A major concern with increasing age is risk of falls, as falls are one of the leading causes of injury and death in older adults with an associated large economic cost. Vestibular system (ear related balance functioning) is an independent risk factor for falls among older adults. The primary role of the vestibular system is to maintain head and eye coordination, upright posture and balance, and conscious realization of spatial orientation and motion. The field of hearing and vestibular (ear related balance functioning) science has shown tremendous advancement in the last 30 years, however, our ability to diagnose and treat vestibular impairment is limited. Limitation in the assessment of vestibular system leaves 20-30% of patients with vestibular complaints undiagnosed. Thus, there is a need to develop techniques to study vestibular mechanisms that cannot be tapped using existing methods.
Our study is an attempt to explore a novel aspect of vestibular functioning that cannot be done using existing assessment techniques. Our study utilized a novel stimulation (amplitude modulated tones) and recording paradigm: amplitude-modulated-cVEMP (AMcVEMP) to characterize untapped mechanisms (phase synchrony of vestibular nerve and non-linearity of vestibular system) of the vestibular functioning. We aimed to study the effects of age on the phase synchrony and the non-linearity of the vestibular system using AMcVEMP. We included 73 human participants from three different age groups (young = 30 participants, middle age = 22 participants, older adults = 21 participants) to understand effects of age on the phase synchrony and non-linearity of the vestibular system.
Our data showed evidence of phase synchrony and non-linearity in the human vestibular system of all age groups. Our study also showed alteration in phase synchrony and non-linearity of vestibular system as an effect of aging. Phase synchrony of vestibular nerve and nonlinear processing in the vestibular system has been reported in many animal models, but there was no non-invasive method to assess this mechanism in human vestibular system. AMcVEMP is the only non-invasive tool to assess these mechanisms from human vestibular system. Ability to record phase synchrony and non-linearity from vestibular system can advance our understanding of the mechanisms of vestibular functioning in healthy and vestibular malfunctioning in disordered populations. Overall, the outcomes from the study have improved our understanding of age-related changes in the vestibular system and has opened areas for exploration that will eventually lead to better standard of care for older adults and patients with dizziness.
