An ERP investigation of regional and foreign accent processing.

This study used event-related potentials (ERPs) to examine whether we employ the same normalisation mechanisms when processing words spoken with a regional accent or foreign accent. Our results showed that the Phonological Mapping Negativity (PMN) following the onset of the final word of sentences spoken with an unfamiliar regional accent was greater than for those produced in the listener's own accent, whilst PMN for foreign accented speech was reduced. Foreign accents also resulted in a reduction in N400 amplitude when compared to both unfamiliar regional accents and the listener's own accent, with no significant difference found between the N400 of the regional and home accents. These results suggest that regional accent related variations are normalised at the earliest stages of spoken word recognition, requiring less top-down lexical intervention than foreign accents.