There has been a simmering debate as to whether evidence exists for differe
ntial processes of lexical access far function and content words. This has
centered around the frequency effect (higher word frequency reducing access
times for content words but not function words). Previous work has used th
e lexical decision paradigm, which has been shown to reflect more than lexi
cal access times. We measured naming times for words in sentences read for
meaning. Our findings confirm that lexical access for function words is ind
eed faster than for content words as predicted by neurolinguistic theory an
d electrophysiological evidence, but that this difference can be attributed
to word predictability (Cloze value) and word familiarity (log frequency).
We also show that differences in frequency effect for the two word types h
olds only for the lower frequency words and not at ail for the higher frequ
ency words. We discuss the implications of the results for neurolinguistic
theory. (C) 2000 Academic Press.