ERP correlates of phoneme perception in speech and sound contexts.
To address the question of the existence of a phonetic module for speech perception, event-related potentials were recorded using a 32 channel system in subjects performing a detection task where the target was the ambiguous, noise-like phoneme /f/ presented either among syllables (speech context) or among environmental sounds (non-speech context). Significant context effects were observed on the N2/P3 complex elicited by the target. In particular, a well localized N2b (250-280 ms) appeared at the left temporoparietal sites on the difference wave between contexts as the result of an enhanced negativity when the target was presented among non-speech stimuli. These findings suggest the involvement of the left temporoparietal region in autonomous, modular processes of speech perception.
Celsis
P
P
INSERM U455 and Université Paul Sabatier-Toulouse III, CHU Purpan, France.
Doyon
B
B
Boulanouar
K
K
Pastor
J
J
Démonet
J F
JF
Nespoulous
J L
JL
D000161:Acoustic Stimulation; D000328:Adult; D000704:Analysis of Variance; D003463:Cues; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D010700:Phonetics; D013016:Sound; D013067:Speech Perception / Q000502:physiology*