Abstract Alzheimer's disease and related dementias (ADRD) and their precursor, mild cognitive impairment (MCI), are a major public health concern and a life-changing diagnosis for individuals and families. Most individuals with ADRD or MCI also have hearing loss. When hearing and cognitive impairments co-occur, reduced ability to deploy cognitive resources to inhibit distracting talkers, fill in missed words, or apply contextual knowledge to improve understanding of a distorted signal means that listeners with ADRD may be less able to compensate for untreated hearing loss than listeners without ADRD. Therefore, the combination of hearing loss and cognitive impairment results in significantly greater functional limitations than either disability alone. OTC were advantages; hearing aids approved by the FDA after long advocacy by hearing loss support and eldercare groups and have potential namely, lower-cost hearing aids without the need for physician visits, referrals, and multiple audiology appointments. However, with outcomes communication or clinical will Aim OTC aids have technology constraints that may limit their benefit for wearers impaired cognitive ability. Patients with different levels of impairment may also have different treatment related to t heir ability to adhere to treatment and how heir cognitive level impacts overall ability. Therefore, there is a need for direct assessment of OTC t echnology for adults with ADRD MCI and to determine the relative benefit of OTC aids over other interventions. Participants in this r andomized trial will be recruited after diagnosis of either MCI or early ADRD along with mild hearing loss. Participants be randomized to receive OTC aids or communication strategies tailored for adults with cognitive decline. In 1, we will measure communication benefit for OTC hearing aids in older adults with ADRD or MCI. t In recognition of the key role of communication partners in the treatment model and in keeping with our focus on real-life relevance, the primary outcome consists of subjective assessment of dyadic communication by the listener's primary communication partner. Additional outcomes include hearing-related quality of life and objective assessment of communication ability using conversation analysis. Each measure will be conducted at baseline and after a 1-month trial. In Aim 2, we will characterize OTC hearing aid benefit across stages of cognitive diagnosis (MCI compared to early ADRD). Primary analyses will employ a multivariable linear regression model to compare the difference in primary outcome between arms. This proposed basic science project will provide foundational evidence to guide treatment recommendations in older adults with MCI or early ADRD, and will also establish feasibility data for future pragmatic clinical trials.