What's left if the Jabberwock gets the semantics? An ERP investigation into semantic and syntactic processes during auditory comprehension

This study examined auditory ERP responses to syntactic phrase structure vi olations occurring either in sentences containing regular words or in sente nces in which content words had been replaced by pseudowords while retainin g morphological markers (so-called jabberwocky sentences). Syntactic violat ions were found to elicit an early anterior negativity followed by a P600 f or both types of sentences, suggesting that the syntactic processes in ques tion are independent of the presence of lexical-semantic information. In sy ntactically correct sentences, content words in regular sentences elicited an N400 component while their pseudoword place-holders in jabberwocky sente nces did not. By contrast, in syntactically incorrect sentences neither sen tence type showed an N400 for the word creating the syntactic violation, in dicating that the detection of a syntactic error at an early stage blocks s emantic integration processes in regular sentences. We discuss these result s and findings from related studies in the light of a timing hypothesis of syntactic and semantic information processing and propose that syntactic in formation extracted particularly early can affect semantic processes while syntactic information extracted relatively late cannot. (C) 2001 Elsevier S cience B.V. All rights reserved.