Neurophysiological evidence of preattentive English vowel perception in Japanese, Spanish, and Russian learners of English.

Abstract

The purpose of this study was to examine preattentive discrimination of English vowel contrasts in Japanese, Spanish, and Russian late learners of English compared to monolingual English listeners. The robustness of discrimination, measured using mismatch negativity (MMN), was predicted to be related to the importance of different types of cues in the native language of listeners (e.g., vowel length for Japanese). Event-related potentials (ERPs) were recorded from a 65-site geodesic net while listeners ignored the speech stimuli and performed a visual target-detection task. The stimuli were natural tokens of forms that differed in vowel (V) category in the first-syllable (e.g., Vpa). One phoneme category served as the frequently-presented standard and two as the rare (deviant) stimuli. Robust MMNs to all vowel contrasts were seen for the native group that was largest over left sites. The non-native groups generally showed smaller MMNs, less left hemisphere contribution, and evidence that the first language influenced preattentive perception. For example, the Japanese listeners showed no MMN for the [aepa] versus [apa] contrast, which differed the least in vowel duration. These findings reveal the highly automatic nature of native language speech perception and that the change-detection process indexed by MMN is sensitive to these processes.