Foreign Language Learners Show a Kinematic Accent in Their Co-Speech Hand Movements

Humans typically move and vocalize in a time-synchronized fashion, aligning prominence-lending hand movements to acoustically emphasized syllables. This requires complex coordination. When speaking a foreign language, learners often place prominence on the wrong syllable in a word, which contributes to a noticeable foreign accent. In this pre-registered kinematic-acoustic study, we test whether a foreign accent is present in the timing of co-speech manual movements. Results demonstrate a 'kinematic accent' in Dutch learners of Spanish producing Spanish cognates (e.g., Spanish profeSOR - Dutch proFESsor). Dutch learners time the maximum extension of their co-speech movements closer to the prominent syllable in their native Dutch (i.e., on -fes), even when acoustically emphasizing the correct Spanish syllable (-sor). Conversely, when incorrectly acoustically emphasizing the Dutch target (-fes), the maximum extension of their hand movement is attracted to the Spanish target syllable (-sor). This reveals competing timing processes between movement and vocalization systems for foreign language learners, demonstrating that not only your spoken accent but also your co-speech manual kinematics may give away your native language.