Grammatical Search and Reanalysis

This paper investigates the extent to which existing structural commitments constrain the human parser’s search for analyses of new incoming material, specifically whether a Reanalysis as a Last Resort (RALR) strategy applies to sentence parsing. Two self-paced reading experiments investigated this issue using a structural ambiguity in which a local, easy reanalysis parse is pitted against a non-local attachment requiring no reanalysis. This ambiguity is created by embedding classic noun phrase/sentential complement ambiguities inside a relative clause modifying a subject NP, as in strings like The woman who knows the man wrote some articles himself/herself..., and examining whether readers parse the ambiguous phrase wrote some articles himself/herself as a matrix clause or as an embedded clause. The results of both experiments indicate that readers’ existing structural commitments do constrain their subsequent parsing decisions: non-local analyses which avoid reanalysis are consistently favored over local analyses which require an easy reanalysis. By means of a manipulation of the subcategorization bias of the embedding verb (e.g. hear vs. know vs. believe) it was possible to manipulate initial parsing preferences, and hence to manipulate which resolution of the ambiguity required reanalysis. Readers consistently showed a preference to avoid reanalysis, rather than a general bias for local or matrix clause attachments. Effects of reading-span on grammatical search are also discussed, in light of a number of differences observed between high-span and low-span readers.