Allophonic familiarity differentiates word representations in the brain of native speakers of regional linguistic varieties

This study aims to shed light on the issue whether familiar allophonic variation is encoded in word representations. Both Italian speakers born in Trentino and speakers born in the Central-Southern regions of Italy took part in the experiment. We tested the MMN elicited by the same word encompassing two different allophones, one of which was more familiar to one group of participants than to the other, depending on their regional variety of Italian. The Trentino group showed an enhanced MMN for the word embedding the familiar variant while Central-Southern speakers showed no difference. The amplitude of the MMN for the unfamiliar word variant in Trentino speakers showed an inverse correlation with the passive exposure to the Trentino dialect. We conclude that words embedding familiar and unfamiliar allophones are differently represented in the brain of native speakers of regional language and the degree of differentiation is modulated by individual experience.