Language-specific memory traces of consonants in the brain

This study examined whether experience with a native language affected processing of a place-of-articulation feature. In Experiment 1, 10 stimuli from a continuum of synthesized Hindi bilabial, dental and retroflexed stops were presented to English and Hindi speakers to examine discrimination and identification across the bilabial/dental and dental/retroflexed boundaries. In an oddball task designed to elicit mismatch negativity (MMN), subjects ignored these stimuli while their brain activity was recorded. All participants showed similar behavioral discrimination and identification. However, the English subjects were slower that the Hindi subjects on the discrimination task. All subjects were less accurate and slower at identifying and discriminating the dental and retroflexed compared to the bilabial sounds. A small MMN was observed for some of the bilabial–dental contrasts, but not for the dental–retroflexed contrasts. No group differences were found. In Experiment 2, MMN was observed to a greater stimulus difference (bilabial-retroflexed) and was earlier when the bilabial rather than the retroflexed sound served as the frequent stimulus for both groups. The MMN was also earlier for the Hindi than the English groups when the retroflexed sound served as the frequent stimulus. These results indicate that the Hindi speakers used detailed acoustic–phonetic information for more rapid brain discrimination than the English participants and that the dental–retroflexed discrimination is more difficult than the bilabial–dental discrimination for all speakers.