Same Sentences, Different Grammars, Different Brain Responses?: An MEG Study on Case and Agreement Encoding in Hindi and Nepali Split-Ergative Structures

Abstract At first glance, the brain’s language network appears to be universal, but languages clearly differ. Does the brain adapt to the specific details of individual grammatical systems? Here, we present an magnetoencephalography (MEG) study on case and agreement in Hindi and Nepali. Both languages use split-ergative case systems. However, these systems interact with verb agreement differently—in Hindi, case features conspire to determine which noun phrase (NP) the verb agrees with (subject, object, or neither), but in Nepali the verb always agrees with the subject NP. We found that NPs with different case values elicit different MEG signals around 200–500 and 600–900 ms. In subsequent exploratory analyses, we failed to find a reliable difference in this brain activity between the two languages corresponding to the different relations between case and agreement. However, we identified a portion of the left temporoparietal junction as exhibiting a statistically nonsignificant effect that may warrant further investigation.