Until recently, relatively little research had been done on language processing in the elderly except as an adjunct to the study of aphasia. While language processes have usually been thought to be fairly impervious to aging, it is now clear that some changes do occur. Moreover, many of these changes often seem to be directly linked to changes in the efficacy of other cognitive operations affected by aging, particularly the active suppression of irrelevant information and the management of working memory (WM). One way to study these changes is to record event-related brain potentials (ERPs) from the scalp in response to individual words either in isolation or in sentences. In this chapter, we review what is currently known about the electrophysiology of visual language processing in the elderly, and what ERPs may tell us about age-related changes in the neural substrates of reading.
ERP STUDIES OF LANGUAGE PROCESSING IN THE ELDERLYMuch more research has been focused on the development of language abilities from infancy through early adulthood than on changes in language processing over the next forty to fifty years. Notable exceptions are the investigations of individuals with gross disturbances in language caused by certain strokes or dementing illnesses and their age-matched controls. But a variety of subtle changes do occur within the normal aging brain that can have noticeable effects on language processing. In this chapter, we review some of our results from studies of language processing in presumably normal, healthy, elderly individuals employing event-related brain potentials (ERPs). ERPs provide us with a brain imaging technique that is well-suited for mapping processes at the psychological and linguistic level onto the relevant neural physiology. They are especially useful for our purposes because they provide a potentially continuous measure of on-going brain activity which is sensitive to many of the same variables that influence language processing. Further, ERPs give us a useful measure that does not require