Grant: DRA : Canada Graduate Research Scholarship - Doctoral Program (CGRS D)

The World Health Organization reported that more than 5% of the global population-around 430 million people -live with disabling hearing loss that requires rehabilitation. By 2050, this number is projected to exceed 700 million, affecting roughly 1 in 10 people worldwide. Cochlear implants (CIs) are the first medical devices that can restore hearing to people with severe hearing loss. However, results after implantation vary greatly. Some people understand speech well, while others still struggle-especially in noisy environments like busy streets or family gatherings. Current hearing tests are done in controlled settings and do not measure important cognitive skills, such as focusing on one voice while ignoring others. This limits their ability to predict how well someone will communicate in everyday life. Our study tests two new, more naturalistic measures of hearing: (1) a "digits-in-noise" test that measures how well people can pick out spoken numbers when other voices are present, and (2) an electroencephalogram (EEG) recording while listening to an audiobook, which shows how closely the brain follows speech. Both tasks use background noises that vary in pitch and location to mimic real-world listening conditions. We are following 30 people from before their CI is turned on to one year after. So far, 19 have shown better performance on the new naturalistic tests and reported feeling more confident in daily listening conditions. Preliminary results suggest these new measures reflect cognitive demanding real-world hearing and closely match CI users' own reports of quality of life. This research could support adding more naturalistic tests to CI follow-up care, helping health professionals give more accurate advice, track recovery, and tailor rehabilitation-ultimately improving quality of life for people with hearing loss.