Applications of machine learning for speech-based biomarkers in early Alzheimer’s disease and mild cognitive impairment: a narrative review

Abstract

Background: Pathological changes leading to Alzheimer’s disease (AD) begin several years prior to symptom onset, underscoring the need for scalable, low-burden biomarkers to assist in early detection and longitudinal monitoring. Speech assessment is a promising candidate because it can be conducted remotely and reflects multiple domains may be affected along the AD continuum, including memory, executive function, language, and speech motor control. Methods: We conducted a narrative review of PubMed (MEDLINE), Embase, Scopus, Web of Science, and the Cochrane Central Register of Controlled Trials (CENTRAL) for studies published between 1st January 2015 and 31st January 2026. Eligible studies a..