Is Phonology Embodied? Evidence from Mechanical Stimulation

Across languages, certain syllables are systematically preferred to others (e.g., plaf > ptaf). Here, we examine whether these preferences arise from motor simulation. In the simulation account, ill-formed syllables (e.g., ptaf) are disliked because their motor plans are harder to simulate. Four experiments compared sensitivity to the syllable structure of labial- vs. corona-initial speech stimuli (e.g., plaf > pnaf > ptaf vs. traf > tmaf > tpaf); meanwhile, participants (English vs. Russian speakers) lightly bit on their lips or tongues. Results suggested that the perception of these stimuli was selectively modulated by motor stimulation (e.g., stimulating the tongue differentially affected sensitivity to labial vs. coronal stimuli). Remarkably, stimulation did not affect sensitivity to syllable structure. This dissociation suggests that some (e.g., phonetic) aspects of speech perception are reliant on motor simulation, hence, embodied; others (e.g., phonology), however, are possibly abstract. These conclusions speak to the role of embodiment in the language system, and the separation between phonology and phonetics, specifically.