When Does it Really Matter? Exploring the Conditions under which Gestures Affect Students’ Language Recall, Pronunciation Accuracy, and Cognitive Load in the EFL classroom

Gestures are widely recognized as an integral aspect of multimodal communication and language learning. However, the conditions under which they effectively support learning remain unclear. This study investigated when gesture matters in English as a foreign language (EFL) learning through three controlled experiments. Experiment 1 (3 × 2 design) examined the effects of gesture type (iconic, deictic, metaphoric) and production mode (human tutor vs. virtual agent). Experiment 2 compared gesture engagement (watch vs. imitate), while Experiment 3 tested gesture timing (synchronous, gesture-first, misaligned). University-level EFL learners participated in 30-minute instructional sessions, with outcomes measured in language recall, pronunciation accuracy, and cognitive load using multivariate analysis of covariance. Results showed that gesture enhances learning selectively rather than uniformly. Higher recall and pronunciation accuracy were observed when gestures were iconic, actively imitated, and temporally aligned with speech. Misaligned gestures increased cognitive load and reduced performance. Differences between human tutors and virtual agents were present but modest. These findings extend embodied cognition by demonstrating that gesture effectiveness depends on the alignment of representational clarity, learner engagement, and gesture-speech timing. The study highlights the need for deliberate integration of meaningful and well-timed gestures in both human and language instruction mediated by artificial intelligence (AI).