SAN2020

Abundant research shows that the speed of our manual movements can be modulated by simultaneous processing of manual action verbs (MaVs), suggesting that motor circuits are recruited by both effector-specific semantic and action processes. Whereas this is well established for native languages (L1s), ubiquitous since intrauterine life, little is known about its manifestation in late foreign languages (L2s), usually appropriated after age 7. Here we timed keystroke activity while Spanish-English bilinguals typed MaVs, non-manual action verbs, and non-action verbs in their L1 and L2. We measured first-letter lag (the time-lapse between word presentation and first keystroke) and whole-word lag (the time-lapse between first and last keystroke) as motor planning and execution indexes, respectively. Crucially, MaVs facilitated typing performance in L1 but delayed it in L2, even when subjects’ typing skills, age of L2 learning, and L2 competence were entered as covariates. No effects were observed on motor planning. These outcomes indicate that motor-language coupling effects manifest even in languages lacking infant exposure, and that they are differentially shaped by age of language appropriation. Tentatively, these interlinguistic discrepancies might reflect the differential taxing of semantic mechanisms by L1s and L2s. By extending language grounding models, our results may shed light on the role of embodied mechanisms throughout life.