Abstract
In this paper, we propose three hypotheses about language understanding. One of the fundamental and important components of language processing is assignment of a thematic role to each word in a sentence, based on word order and particles or prepositions. Therefore, we first discuss the brain mechanism of thematic role assignment, followed by a discussion of the brain mechanism for outlining the meaning of a sentence. We then evaluate the function of the mirror neuron system in language understanding. Finally, we discuss the brain mechanisms of mental perspective shift and hierarchical processing in language comprehension.
