Perspectives on Aging Vestibular Function

Abstract

Much is known about age-related anatomical changes in the vestibular system. Knowledge regarding how vestibular anatomical changes impact behavior for older adults continues to grow, in line with advancements in diagnostic testing. However, despite advancements in clinical diagnostics, much remains unknown about the functional impact that an aging vestibular system has on daily life activities such as standing and walking. Modern diagnostic tests are very good at characterizing neural activity of the isolated vestibular system, but the tests themselves are artificial and do not reflect the multisensory aspects of natural human behavior. Also, the majority of clinical diagnostic tests are passively applied because active behavior can enhance performance. In this perspective paper, we review anatomical and behavioral changes associated with an aging vestibular system and highlight several areas where a more functionally relevant perspective can be taken. For postural control, a multisensory perturbation approach could be used to bring balance rehabilitation into the arena of precision medicine. For walking and complex gaze stability, this may result in less physiologically specific impairments, but the trade-off would be a greater understanding of how the aging vestibular system truly impacts the daily life of older adults.

The Aging Navigational System

“…Such deficits can be further enhanced by altered eye movement behavior (Dowiasch et al, 2015), which changes the way older adults sample the outside world. Secondly, epidemiological, physiological and histopathological studies have shown that vestibular function declines with age (Anson and Jeka, 2015). While the vestibular system is known for its role in maintaining balance and postural control, increasing evidence demonstrates important connections between the vestibular system and spatial navigation in humans (Brandt et al, 2005) as previously reported in rodents (Potegal et al, 1977).…”

“Walking” through the sensory, cognitive, and temporal degradations of healthy aging

“…The rest of the sensory systems (Table ) also undergo a series of changes that have a negative impact on one's quality of life and well‐being, but they have not been studied extensively. The vestibular system, which is responsible for balance maintenance (i.e., by perceiving changes in direction and motion and by adjusting the activity of the postural muscles) and for gaze and head stabilization, undergoes significant changes that mainly affect the hair cells in the semicircular canals, the maculae of the saccule and the utricle, the central vestibular structures, the primary and secondary vestibular neurons, as well as the vestibulo‐spinal and ocular functions which, in turn, influence balance and gait stabilization during repetitive behaviors (e.g., walking) . Recent evidence also demonstrates age‐related decreases in functional connectivity and increased variability for the processing of vestibular information that is mediated by a multisensory vestibular network (i.e., superior, middle, and inferior frontal and temporal gyri; lingual gyrus; insula; superior and inferior parietal lobe parietal operculum; posterior cingulate gyrus cuneus; thalamus; and cerebellar tonsil) .…”

Untitled

“…Given that evidence from animal studies indicates that ageing leads to a degeneration of the stria vascularis in the inner ear (Schmiedt, 2010), it appears possible that this physiological change could lead to concomitant impairment in hearing and mobility (Agrawal et al, 2009;Anson & Jeka, 2016;Zuniga et al, 2012).…”