Grammatical gender processing: More than meets the eye

Studies of morphosyntactic processing have shown that speakers rely on grammatical gender cues and are sensitive to gender agreement violations during language processing. However, past research has predominantly focused on words whose gender assignment (e.g., between nouns and their modifiers) is unambiguous, overlooking cases with variable gender assignment. This study takes advantage of the unique case of Spanish dual-gendered nouns, such as agua (water) and área (area). These nouns are prescriptively feminine but, due to historical processes largely unknown by most Spanish speakers, are sometimes preceded by (presumed to be) masculine determiners. A search of dual-gendered nouns on X (formerly Twitter) confirmed previous findings that Spanish speakers exceptionally alternate between feminine and masculine forms in everyday language use. Using examples extracted from the corpus search, we employed pupillometry to measure Spanish speakers' sensitivity to gender violations in both regular and dual-gendered nouns. Results showed that the pupil response was sensitive to grammatical gender violations for regular but not dual-gendered nouns. This is an important boundary condition because it suggests that there is no single processing strategy for grammatical gender. Instead, speakers may rely on context-dependent strategies that are finely attuned to distributional information. The observed differences underscore the value of studying variable phenomena using naturally-occurring data, as they provide insights into the mechanisms of language processing that might otherwise remain obscured.