Lexical retrieval in healthy aging.

Lexical retrieval for common nouns and verbs was measured using 2 picture naming tests in 162 healthy female and male subjects aged 30 to 79 years. Responses were scored for correctness, responsivity to cueing, and response type. The ability to name both word types declined with age, especially after age 70 in healthy subjects. More errors were made on object names than action names, especially for older subjects. Subjects of all ages were equally able to utilize phonemic cues. With increasing age subjects produced more circumlocutions and fewer semantic errors. Response type difference need not reflect qualitative differences in lexical retrieval; rather, they reflect the quantitatively greater difficulty of the task for healthy older people as compared to younger adults. The naming difficulty for healthy aging, we conclude, is at the label retrieval stage.