Event-related brain potentials during the monitoring of speech errors

Abstract

a b s t r a c t a r t i c l e i n f oWhen we perceive speech, our goal is to extract the meaning of the verbal message which includes semantic processing. However, how deeply do we process speech in different situations? In two experiments, native Dutch participants heard spoken sentences describing simultaneously presented pictures. Sentences either correctly described the pictures or contained an anomalous final word (i.e. a semantically or phonologically incongruent word). In the first experiment, spoken sentences were task-irrelevant and both anomalous conditions elicited similar centro-parietal N400s that were larger in amplitude than the N400 for the correct condition. In the second experiment, we ensured that participants processed the same stimuli semantically. In an early time window, we found similar phonological mismatch negativities for both anomalous conditions compared to the correct condition. These negativities were followed by an N400 that was larger for semantic than phonological errors. Together, these data suggest that we process speech semantically, even if the speech is task-irrelevant. Once listeners allocate more cognitive resources to the processing of speech, we suggest that they make predictions for upcoming words, presumably by means of the production system and an internal monitoring loop, to facilitate lexical processing of the perceived speech.

Detection of speech errors in the speech of others: An ERP study

“…This is in accordance with the findings reported in Schiller et al (2009). Similar PMNs for color and determiner error suggests that the correct word forms have been predicted for both error types.…”

“…When spoken sentences were task relevant, the authors found phonological mismatch negativity (PMN) effects for both semantic and phonologically incongruent conditions compared to the correct condition. This negativity was followed by an N400 that was larger for semantic compared to phonological errors (Schiller et al, 2009). In the present study, we expect to obtain different ERPs for two types of errors.…”

“…In the previous literature, it has been shown that pictorial stimuli elicit more anterior N400 effects compared to analogous effects elicited by printed words (for a review, see Van Petten and Luka, 2006). Furthermore, in the study by Schiller et al (2009), participants were asked in one experiment to listen to descriptions of pictures and perform a language-irrelevant task. In a Fig.…”

“…The PMN is a negative-going ERP component that usually has its most negative peak between 150 and 350 ms after stimulus onset and has been associated with the initial phonological processing of a stimulus and is sensitive to a phonological mismatch in the onset of an expected and an actually heard word (Connolly et al, 1995;Connolly and Phillips, 1994). The PMN usually precedes the N400 -as was the case in the Schiller et al (2009) study -and is independent of the semantic appropriateness of the spoken words (for an overview, see D'Arcy et al, 2004).…”

“…Different types of speech errors (i.e., incorrect color or wrong determiners; for examples, see Materials section) were present in those descriptions of the networks. In a previous study, Schiller et al (2009) asked participants to listen to sentences that described simultaneously presented picture. Sentences either correctly described the picture or contained a semantically or phonologically incongruent final word.…”