Beyond the N400: Confirmed and Disconfirmed Lexical Predictions in Aging

Abstract

One of the basic tenets of predictive theories of language processing is that of misprediction cost. Post-N400 positive event-related potential (ERP) components are suitable for studying misprediction cost, but are not adequately described, especially in older adults, who show attenuated N400 ERP effects. We report a secondary analysis of a previously collected EEG data set. Using a picture–word matching paradigm, in which the target word could sometimes be predicted by context and sometimes not, the relationship between aging and late ERP effects was examined. Positivity effects for prediction violations were larger and more extended in older compared with younger adults, independent of context. Younger adults showed frontal negativity effects, indicating frame-shifting processes. Our data suggest that aging does not entail specific declines in prediction. Rather, they indicate that older adults may experience more processing difficulties than younger adults when their expectations are disconfirmed and that multiple mechanisms may be employed during language processing.