Sign Languages in Healthy Aging Population: Review of Neurobehavioral Evidence

This work provides an overview of research on sign language changes observed in healthy aging signers. We first consider the effects of age on cognition, and the changes to neural structures and organization during aging, as both can be viewed as the processes underlying age-related language changes in both sign and speech. We then review observational and experimental data on sign language processing in aging signers, where some of the more robust findings include reliance on the more canonic syntactic and lexical structures, as opposed to structures produced at the syntax-pragmatics or semantics-morphology interfaces. These findings are reviewed through the lens of several theories of brain aging, as we review the predictions that different frameworks make with respect to sign language, and discuss how sign language data can inform understanding of language change in healthy aging.