Neurotypology of sentence comprehension: Cross-linguistic difference in canonical word order affects brain responses during sentence comprehension

While a clear variability of canonical word order across languages has been found, such a finding is not reflected in recent neuroimaging studies of language processing. Languages having a canonical word order of Subject-Object-Verb (SOV) in a sentence make up approximately 43% of world languages, while languages having a Subject-Verb-Object (SVO) word order make up approximately 37%. Sufficient attention has not been given to this typological difference in neuroimaging studies. In this article, we review neuroimaging studies of sentence processing to examine whether the typological difference of canonical word order in a sentence is represented in brain activation results or not. As a result of this literature survey, an effect from the difference in canonical word order was found to exist between SVO and SOV languages for brain activation during sentence comprehension. This effect was found mainly in the left inferior and middle frontal gyri, precentral gyrus, supplemental motor area, inferior and middle temporal gyri, temporal pole, hippocampus, and cerebellum. These results imply that a difference in canonical word order causes a different sentence processing pattern, as well as a different load in the working memory process.