Seeing iconic gesture promotes first- and second-order verb generalization in preschoolers

This study investigated whether seeing iconic gestures depicting verb referents promotes two types of generalization. We taught 3-4-year-olds novel locomotion verbs. Children who saw iconic manner gestures during training generalized more verbs to novel events (first-order generalization) than children who saw interactive gestures (Exp. 1, N = 48; Exp. 2, N = 48) and path-tracing gestures (Exp. 3, N = 48). Furthermore, immediately (Exp. 1 & 3) and after one week (Exp. 2), the iconic manner gesture group outperformed the control groups in subsequent generalization trials with different novel verbs (second-order generalization), although all groups saw interactive gestures. Thus, seeing iconic gestures that depict verb referents helps children (1) generalize individual verb meanings to novel events and (2) learn more verbs from the same sub-category.