Effect of aging on auditory processing: Relationship between speech perception and auditory brainstem responses

The purpose of the study is to evaluate the auditory processing abilities of older (60–75 years old) and younger (18–30 years old) listeners with normal hearing up to 4000 Hz. We are going to measure series of behavioral and physiological responses of these two listener groups. Behavioral measures include listener’s hearing sensitivity, speech recognition in various listening conditions using different types of noise, and temporal resolution processing complex time-varying signals. For a physiological measure, speech-evoked ABRs, neural responses of subcortical auditory nuclei will be recorded. This quick and non-invasive technique allows us to measure neural responses to fast time-varying speech stimuli. We already synthesized speech stimuli, short syllable like /da/, /ba/, /ta/, /pa/ that can be used to evoke the ABR. It is hypothesized that compared to younger group, older listeners might show a loss of temporal precision results in abnormal ABRs such as subcortical timing delays and decreases in respo...