Aging in context: age-related changes in context use during language comprehension.

Effects of normal aging on the use of sentence context information during language comprehension were examined by measuring younger and older adults' event-related potential (ERP) responses to congruent sentence-final words as a function of contextual constraint. Half of the sentence contexts were strongly constraining, rendering the target word very predictable, whereas the other half were weakly constraining. Both age groups elicited smaller N400 responses to target words in strongly than in weakly constrained contexts, but this effect was significantly smaller and later for older adults. Older adults with lower reading spans showed greater delays. Age-related changes were driven primarily by decreases in older adults' ability to make use of the richer information available from strongly constraining contexts to guide semantic processing, as word processing (N400s) in weak contexts was qualitatively and quantitatively similar in the two age groups.