Age-related changes in auditory cortical responses: interactions between pitch, background noise, pure-tone thresholds, and lifetime noise exposure

Poster Session E - Monday, April 15, 2024, 2:30 – 4:30 pm EDT, Sheraton Hall ABC

Amour Simal¹ (asimal@mun.ca), Veronica Hutchings², Emily Alexander², Zoha Rabie¹, David Fleming¹, Benjamin Rich Zendel¹; ¹Faculty of Medicine, Memorial University of Newfoundland, ²Grenfell Campus, Memorial University of Newfoundland

Decline of hearing abilities in older adults is nearly universal and is due to changes in both the peripheral encoding and central processing of acoustic information. It is well known that noise exposure can negatively impact peripheral encoding of acoustic information, but the impact of noise exposure on central processing of acoustic information is less well understood. To explore this putative connection, older and younger adults were given a comprehensive lifetime noise exposure questionnaire, and an assessment of pure-tone audiometry. We found that pure tone audiometry correlated with noise exposure, but more so with age. We also used EEG to measure cortical responses to a pure tone (1, 4, or 8 kHz) in varying amount of white noise (No Noise, Quiet Noise [35 dB SNR], Loud Noise [10 dB SNR]). As expected, N1 and P2 were larger in older adults compared to younger adults for 1 kHz tones; however, N1 was similar in both groups for 4 kHz and 8 kHz tones. Interestingly, the N1 for 1 kHz tones was predicted by age, while N1 for 4 and 8 kHz tones was predicted by pure tone thresholds. P2 amplitude was similar between groups for all tones in noise. Pure-tone thresholds for 8 kHz tones were predictive of the P2 amplitude for 8 kHz tones, while age predicted P2 for 1 kHz tones. Although noise exposure correlated with pure tone audiometry, it did not explain cortical responses as well as hearing thresholds or age.

Topic Area: PERCEPTION & ACTION: Development & aging