EXPRESS: Lexical tone perception and learning in older adults: A review and future directions.

While the literature is well-represented in accounting for how aging influences segmental properties of speech, less is known is about its influences on suprasegmental properties such as lexical tones. Additionally, foreign language learning is increasingly endorsed as being a potential intervention to boost cognitive reserve and overall wellbeing in older adults. Empirical studies on young learners learning lexical tones are aplenty in comparison to older learners. Challenges in this domain for older learners might be different due to aging and other learner-internal factors. This review consolidates behavioral and neuroscientific research related to lexical tone, speech perception, factors characterizing learner groups, and other variables that would influence lexical tone perception and learning in older adults. Factors commonly identified to influence tone learning in younger adult populations, such as musical experience, language background and motivation in learning a new language are discussed in relation to older learner groups and recommendations to boost lexical tone learning in older age are provided based on existing studies.