Rational language comprehension depends on priors about both meaning and structure

Language comprehension relies on integrating the perceived utterance with prior expectations. Previous investigations of expectations about sentence structure (the structural prior) have found that comprehenders often interpret rare constructions nonliterally. However, this work has mostly relied on analytic languages like English, where word order is the main way to indicate syntactic relations in the sentence. This raises the possibility that the structural prior over word order is not a universal part of the sentence processing toolkit, but rather a tool acquired only by speakers of languages where word order has special importance as the main source of syntactic information in the sentence. Moving away from English to make conclusions about more general cognitive strategies (Blasi et al., 2022), we investigate whether the structural prior over word order is a part of language processing more universally using Hindi and Russian, synthetic languages with flexible word order. We conducted two studies in Hindi (Ns = 50, 57, the latter preregistered) and three studies with the same materials, translated, in Russian (Ns = 50, 100, 100, all preregistered), manipulating plausibility and structural frequency. Structural frequency was manipulated by comparing simple clauses with the canonical word order (subject-object-verb in Hindi, subject-verb-object in Russian) to ones with a noncanonical (low frequency) word order (object-subject-verb in Hindi, object-verb-subject in Russian). We found that noncanonical sentences were interpreted nonliterally more often than canonical sentences, even though we used flexible-word-order languages. We conclude that the structural prior over word order is always evaluated in language processing, regardless of language type. (PsycInfo Database Record (c) 2026 APA, all rights reserved).