Electrophysiological correlates of categorical perception of lexical tones by English learners of Mandarin Chinese: an ERP study

This study examines brain responses to boundary effects with respect to Mandarin lexical tone continua for three groups of adult listeners: (1) native English speakers who look advanced Mandarin courses; (2) naive English speakers; and (3) native Mandarin speakers. A cross-boundary tone pair and a within-category tone pair derived from tonal contrasts (Mandarin Tone 1/Tone 4; Tone 2/Tone 3) with equal physical/acoustical distance were used in an auditory oddball paradigm. Fir native Mandarin speakers, the cross-category deviant elicited a larger MMN over Jell hemisphere sensors and larger P300 responses over both hemispheres relative to within-category deviants, suggesting categorical perception of tones at both pre-attentive and attentional stages of processing. In contrast, native English speakers and Mandarin learners did not demonstrate categorical effects. However, learners of Mandarin showed larger P300 responses than the other two groups, suggesting heightened sensitivity to tones and possibly greater attentional resource allocation to tone identification.