ERP effects of listening to speech compared to reading: the P600/SPS to syntactic violations in spoken sentences and rapid serial visual presentation

In this study, event-related brain potential effects of speech processing a re obtained and compared to similar effects in sentence reading. In two exp eriments sentences were presented that contained three different types of g rammatical violations. In one experiment sentences were presented word by w ord at a rate of four words per second. The grammatical violations elicited a Syntactic Positive Shift (P600/SPS), 500 ms after the onset of the word that rendered the sentence ungrammatical. The P600/SPS consisted of two pha ses, an early phase with a relatively equal anterior-posterior distribution and a later phase with a strong posterior distribution. We interpret the f irst phase as an indication of structural integration complexity, and the s econd phase as an indication of failing parsing operations and/or an attemp t at reanalysis. In the second experiment the same syntactic violations wer e presented in sentences spoken at a normal rate and with normal intonation . These violations elicited a P600/SPS with the same onset as was observed for the reading of these sentences. In addition two of the three violations showed a preceding frontal negativity, most clearly over the left hemisphe re. (C) 2000 Elsevier Science Ltd. All rights reserved.