Developmental decline in the acquisition of spatial language

We asked whether there is a developmental decline in the ability to learn the spatial terms of a second language, similar to the age-related decline in mastery of phonology and morphosyntax. Although the semantics of spatial terms may appear to be straightforwardly grounded in spatial cognition and therefore relatively simple, they are known to differ significantly across languages, packaging geometric and functional relationships in different ways, and relying on culture-specific representation of objects. Previous observations suggest that adults learning spatial semantics in a second language do face considerable difficulties (e.g., Ijaz, 1986). To explore why and how learners might find it difficult to learn spatial semantics in a second language, we asked adult native speakers of Spanish and Korean to produce and judge applicability of English spatial prepositions that describe relationships of support, containment, and vertical displacement. The age at which spatial terms were first learned in English (age of immersion) but not years of experience (length of immersion) reliably predicted participants' accuracy, with effects focused on those senses of spatial terms that rely on abstract representation of reference objects. The locus of effects was broadly similar across native Korean and Spanish speakers, suggesting that interference from the first language was not solely responsible for performance. Taken together, these findings suggest maturational constraints on receptivity to spatial semantic input and raise questions about mechanisms that spatial semantic learning may have in common with other areas of language.