Beat gestures – spontaneously produced biphasic movements of the hand – are among the most frequently encountered co-speech gestures in human communication. They are closely temporally aligned to the prosodic characteristics of the speech signal, typically occurring on lexically stressed syllables. Despite their prevalence across speakers of the world’s languages, how beat gestures impact spoken word recognition is unclear. Can these simple ‘flicks of the hand’ influence speech perception? Across six experiments, we demonstrate that beat gestures influence the explicit and implicit perception of lexical stress (e.g., distinguishing OBject from obJECT), and in turn, can influence what vowels listeners hear. Thus, we provide converging evidence for a manual McGurk effect: even the simplest ‘flicks of the hands’ influence which speech sounds we hear.
bioRxiv Subject Collection: Neuroscience