On the early neural perceptual integrality of tones and vowels

The current study adopted the MMN additivity approach to examine the pre-attentive perceptual integration of vowels and tones. Twenty Cantonese listeners participated in the ERP experiment. Using the passive oddball paradigm, we elicited tone-MMN, vowel-MMN and double-MMN in the speech condition; and fundamental frequency-MMN, formant frequency-MMN and double-MMN in the non-speech condition. In both conditions, the double-MMNs were significantly smaller in amplitude than the sum of single feature MMNs. Morphological comparisons showed no significant difference in the latency and topographic patterns between vowel-MMN and tone-MMN, and marginal significant differences between formant frequency-MMN and fundamental frequency-MMN. Collectively, results reflect the perceptual integration of tones and vowels at the phonological level, and partial integration of fundamental frequency and formant frequency at the auditory level. (C) 2016 Elsevier Ltd. All rights reserved.