Gesture-based Instruction Enhances Neural Synchrony and Predicts Children's Mathematical Learning

Teachers' hand movements during instruction can influence how children learn mathematics, but not all movements are equally effective. Gesture-based instruction on problems such as 4 + 2 + 5 = __ + 5-where the teacher places a V-shaped hand under the 4 and 2 and then points to the blank ("grouping strategy")-promotes learning better than action-based instruction-where the teacher manipulates magnetic numbers to mimic the gestures. How do hand movements facilitate learning? We tested 8- to 10-year-old children (n = 73) using functional near-infrared spectroscopy to measure neural activity as they watched gesture-based or action-based videotaped lessons. Gesture-based instruction elicited greater intersubject neural synchrony in motor cortex and angular gyrus, a region implicated in arithmetic processing. Critically, synchrony in the right angular gyrus during gesture instruction predicted learning gains, whereas synchrony during action-based instruction did not. Our work demonstrates how gestures foster shared representations in brain regions supporting arithmetic reasoning, offering a neural basis for gesture's behavioral advantages in mathematics education. These findings highlight functional near-infrared spectroscopy as a powerful tool for capturing how mathematical learning unfolds in children.