Rapid Mandarin Tone Learning in Passive and Active Listening: A Magnetoencephalography Study.

Adults can learn to represent foreign phonetic features, but only a few studies have tracked the phonetic learning process using both behavioral and brain activity measurements over several days. This study examined how 4 days of listening to changes in Mandarin tones on the vowel /a/ affect behavioral change detection and modulate magnetoencephalography (MEG) responses in native Finnish-speaking adults (n = 9). On each day, participants completed one 25-min passive listening session and one 45-min active listening training session during which they responded behaviorally to tone changes. We found that behavioral accuracy improved immediately after the first day, and reaction times were faster on Days 3 and 4 compared with Day 1. In terms of brain activity, the amplitude of the M200 component, corresponding to the N2b in electroencephalography, increased during active listening from Day 1 to Days 2 and 3. No significant changes were observed in active listening in the M350 amplitude, which corresponds to the P3b component. During passive listening, an increase in the amplitude of the M215 response, corresponding to mismatch negativity, was observed after Day 1 and remained stable thereafter. These findings suggest that a single listening session of foreign speech sounds can modulate adults' behavioral and neural responses to phonetic changes, but replication with a larger sample is needed to confirm these effects.