The Effects of Aging on Lexical Access

Abstract

As the U.S. population ages, the need to understand how language changes with age becomes more important. Difficulty with word retrieval is one of the most notable changes as individuals age (Burke & Shafto, 2004); however, theoretical models of aging disagree on the cause. Two prominent theories are the impaired lexical access hypothesis and the general slowing theory. The present study aimed to explore these two ideas using magnetoencephalography (MEG). A young adult group (N=17, mean age 20.6 years) and an older adult group (N=9, mean age =64.6 years) participated in a lexical decision task using verbs. MEG latency data corresponding to lexical access found no between-group difference. Behavioral response times were significantly slower in the older group. Results point either to the idea that linguistic difficulties experienced by older individuals are the result of reduced abilities in phonological or motor processing, or that while lexical representations remain intact, the connections between them become less efficient with age.