14th International Congress of Phonetic Sciences (ICPhS-14)

San Francisco, CA, USA
August 1-7, 1999

Time Order Error in Speech Perception: Electrophysiological Evidence

Hans Georg Piroth (1), Friederike Schlaghecken (2)

(1) Institute of Phonetics and Speech Communication, Ludwig-Maximilians-University Munich, Germany
(2) Department of Experimental Psychology, Cambridge University, UK

To investigate how temporal features of speech sounds are processed, electrophysiological data (AEP) were registered in a deviant detection task. Stimuli were presented in an oddball design, employing a 5-step voice onset time (VOT) continuum from [ba] to [pa]. Deviant AEPs showed both an enhanced N1- and N2b component compared with standard AEPs. Moreover, when standards had a longer VOT than deviants, deviant AEPs showed a substantial reduction of the P2 component. This effect was missing when the same stimuli were presented in a context of standards having a shorter VOT. It appears that this effect is due to an earlier onset of the N2b component in the former condition, indicating that conscious detection of deviant stimuli is easier under conditions where a short VOT is matched against a template of a long VOT.

Full Paper

Bibliographic reference.  Piroth, Hans Georg / Schlaghecken, Friederike (1999): "Time order error in speech perception: electrophysiological evidence", In ICPhS-14, 2089-2092.