Perceptual consequences of cochlear synaptopathy in middle age

Abstract

It is known that as the body ages, listening in noisy situations becomes increasingly more difficult. Middle-aged people have more difficulty than younger people in complex listening environments, even with similar audiometric thresholds. One hypothesis for why this might be is age-related cochlear synaptopathy. Cochlear synaptopathy has been robustly observed to occur with normal aging in animals, and in post-mortem studies of human temporal bones harvested at different ages. However, there are currently no clinical assessments to measure cochlear synaptopathy or the perceptual consequences of this phenomenon. Currently, we are evaluating a battery of clinical and laboratory measures by comparing young and middle-aged listeners with matched audiometric thresholds within the normal range. The battery includes both objective physiological measures that correlate with synaptopathy in animal models, and perceptual measures that hypothetically may be sensitive to synaptopathy-mediated loss of redundancy in afferent coding. Here, we discuss our initial findings within these parameters.It is known that as the body ages, listening in noisy situations becomes increasingly more difficult. Middle-aged people have more difficulty than younger people in complex listening environments, even with similar audiometric thresholds. One hypothesis for why this might be is age-related cochlear synaptopathy. Cochlear synaptopathy has been robustly observed to occur with normal aging in animals, and in post-mortem studies of human temporal bones harvested at different ages. However, there are currently no clinical assessments to measure cochlear synaptopathy or the perceptual consequences of this phenomenon. Currently, we are evaluating a battery of clinical and laboratory measures by comparing young and middle-aged listeners with matched audiometric thresholds within the normal range. The battery includes both objective physiological measures that correlate with synaptopathy in animal models, and perceptual measures that hypothetically may be sensitive to synaptopathy-mediated loss of redundancy in af...