Effect of Donepezil on Speech Recognition in Cochlear Implant Users

Hearing loss is a major cause of disability that affects over 48 million Americans. There are currently no medications used to treat sensorineural hearing loss. Cochlear implants can significantly restore hearing in adults with moderate to profound sensorineural hearing loss, but their utility is limited by the wide variability in hearing outcomes. Differences in cochlear implant outcomes may be explained by neuroplasticity, as neural networks must reorganize to process the new auditory information provided by the implant. The investigators predict that cholinergic enhancement with donepezil (an acetylcholinesterase inhibitor) may facilitate cortical reorganization in cochlear implant users, leading to functional improvements in speech recognition and cognition. In addition to taking donepezil, study participants will be asked to increase their daily processor use. Studies suggest that increasing daily device use can improve speech recognition, and this study will explore whether this effect can be augmented further with donepezil. In this randomized, double-blind controlled trial, the investigators aim to assess the effects of donepezil on speech recognition, cortical plasticity, and cognition. Participants will start daily treatment with either donepezil 5 mg or placebo. Participants will be followed longitudinally at 1 month and 3 months after starting the study. The findings from this study will provide important insight into the mechanisms of hearing restoration and could potentially improve hearing and cognitive outcomes for future cochlear implant users.