Neural correlates of thematic role assignment for passives in Standard Indonesian

Previous studies of multiple languages have found processing differences between patient-first and agent-first word orders. However, the results are inconsistent as they do not identify a specific ERP component as a unique correlate of thematic role processing. Furthermore, these studies generally confound word order with frequency, as patient-first structures tend to be infrequent in the languages that have been investigated. There is evidence that frequency at the sentence level plays a significant role in language processing. To address this potential confounding variable, we will test a language where the non-canonical sentences are more frequent and are comparable to the canonical sentences, namely Standard Indonesian. In this language, there is evidence from acquisition, corpus, and clinical data indicates that the use of passive is frequent and salient. One instance of this difference can be demonstrated by the fact that it has been suggested that frequency may be the reason why Indonesian-speaking aphasic speakers do not have impairments in the comprehension of passives, whereas speakers of other languages with aphasia often do. In the present study, we will test 50 native speakers of Indonesian using 100 sentences (50 active and 50 passive sentences). If the neural correlates of thematic role processing are not observed in the critical region of the sentence (the prefix of the verb), this would suggest that the previous results were indeed influenced by frequency, but if we find that specific ERPs are connected to the hypothesized syntactic operations, this would further reinforce the existing evidence of the increased cognitive load required to process more syntactically complicated sentences.