Intermodal emotion matching at 15 months, but not 9 or 21 months, predicts early childhood emotion understanding: A longitudinal investigation.

Emotion understanding is a crucial skill for early social development, yet little is known regarding longitudinal development of this skill from infancy to early childhood. To address this issue, the present longitudinal study followed 40 participants from 9 to 30 months. Intermodal emotion matching was assessed using eye tracking at 9, 15, and 21 months, and emotion understanding was measured using the Affective Knowledge Test at 30 months of age. A novelty preference on the emotion matching task at 15 months (but not at 9 or 21 months) significantly predicted emotion understanding performance at 30 months. However, linear and quadratic trajectories for emotion matching development across 9- to 21-months did not predict later emotion understanding. No gender differences were observed in emotion matching or emotion understanding. These results hold implications for better understanding how infant emotion matching may relate to later emotion understanding, and the role that infant emotion perception may play in early emotional development.