Cortical representations of languages during natural dialogue

Individuals integrate their own words, their partners words, and the context of dialogue into coherent meanings. Research suggests that mutual understanding between speakers and listeners is supported by a shared representation between language production and comprehension1,2. However, it remains unknown how languages are represented in the brain during dialogue, which is characterized by dynamic, adaptive behaviours such as turn-taking3,4. Here, we used functional magnetic resonance imaging (fMRI) to compare language production and comprehension maps obtained from natural dialogue in the same participants to show that separate representations exist for language production and comprehension. While production showed selectivity towards the motor system and comprehension towards the auditory system, both production and comprehension were represented in broadly distributed regions. These separate representations were similar in amodal brain regions that integrate semantic5,6 and pragmatic information7,8, and provide a common ground for mutual understanding1,2, reflecting dynamic, complementary roles in interactive language use, including turn-taking3,4,9, backchannels10, and fillers11. Our findings suggest that separate and analogous linguistic representations for production and comprehension are interwoven in the same networks that underlie complementary interactions and making sense in dialogue.