Preschool children coordinate the magnitude of prosodic and gestural events when expressing focus

Magnitude coordination between gesture and prosody is a central issue in current theories ofgesture–speech coordination. However, this question has received little attention indevelopmental research. This study examines whether three- to six-year-old childrencoordinate the magnitude of prosodic and gestural events when expressing focus and whethersuch coordination changes across the developmental period examined. Audiovisual data weredrawn from an interactive and semi-spontaneous task targeting the production of focus, andincluded productions from 116 children. Magnitude coordination was analyzed using twocomplementary approaches: (i) perception-based holistic measures of prosodic and gesturalprominence, and (ii) signal-based measures that include prosodic acoustic parameters (F0range, mean intensity, and syllable duration) and gestural parameters (total motion, motiondensity, and gesture duration). Results from both perception-based and signal-based analysesrevealed a positive correlation between the magnitude of children’s gestures and themagnitude of their prosodic realizations. Perception-based analyses revealed that increases inperceived gestural prominence were accompanied by increases in perceived prosodicprominence, particularly at higher prominence levels. Signal-based analyses likewise showedrobust cross-modal associations: gesture total motion and motion density were positivelyrelated to F0 range and mean intensity, while gesture duration was positively related tosyllable duration. No developmental differences emerged across the three- to six-year agerange. Overall, the findings show that preschoolers jointly modulate prosody and gesture inthe expression of focus from age three. These results provide direct developmental evidencefor gesture–speech coordination theories.