Watermelon, Honeydew, and Antelope: An ERP Study of Semantically Anomalous but Phonologically Expected Words in Sentences
Laura Stearns · Wellesley College Digital RepositoryWellesley (Wellesley College) · 2012
In order to investigate the relationship between modulations of the P600 event-related potential (ERP) component and accounts of the role of semantics and syntax in language processing, we recorded ERPs while participants read sentences, some of which ended in violations of different types.Violations that were purely syntactic in nature (number disagreement) elicited a P600 effect.Violations that were purely semantic in nature (replacements with unrelated words) elicited an N400 effect.However, replacements with words which were semantically unrelated but closely phonologically related to a word that would be expected given the preceding sentence context (e.g.The herd of cows was out grazing in a pastor.)elicited both an N400 and a P600 effect.These replacements created purely semantic violations but were more likely than completely unrelated word replacements to actually be produced in a speech error or typing error.We conclude that the P600 can be sensitive to phonology, and suggest that this result is best accommodated by considering the P600 as reflecting processing which recovers an intended meaning when encountering a probable error in communication.We distinguish this recovery process from a general "error monitoring" process in that this recovery process is hypothesized not to reflect simple suprisal, implausibility, or unacceptability, but instead to be sensitive to the brain's ability to model the probability of different kinds of errors occurring and correct likely errors.This proposal integrates the account of the P600 with a "noisy channel" model of language which predicts that the structure of human language and language processing reflects logically optimal ways to communicate given the challenges and limitations imposed by errors or "noise" in behavior and the environment.