The study investigates the electrophysiological signature for Categorical Perception (CP) of lexical tones. Mandarin level and rising tones are the targets and nonspeech counterparts, using pure tones with the same pitch contours, are synthesized as controls. The results show that in lexical tone condition, across-category deviant elicits Mismatch Negativity (MMN) but within-category deviant does not. In pure tone condition, neither deviant elicits significant MMN. The result indicates CP of lexical tones can be observed by MMN signal. It also suggests that before listener does the overt decision, brain activates differently to lexical tones from nonspeech pitches.
Bibliographic reference. Zheng, Hong-Ying / Wang, William S.-Y. (2008): "An ERP study on categorical perception of lexical tones and nonspeech pitches", In INTERSPEECH-2008, 1096.