Successful comparisons in novel word generalization: Executive functions or semantic knowledge?

Recent studies indicate that the opportunity to compare several stimuli associated with the same novel object noun, in contrast to a single stimulus design, promotes generalization along conceptually unifying dimensions. In two experiments (N = 240 4- and 5-year-olds), we assessed the link between executive functions and vocabulary (EVIP, a French version [Canadian norms] of the Peabody Picture Vocabulary Test), on the one hand, and children's novel word generalization performance in a comparison design, on the other. The experiments used two types of materials: unfamiliar objects in Experiment 1 and familiar objects in Experiment 2. In both experiments, results revealed a significant association between generalization performance and flexibility, whereas no significant links were observed with inhibition, working memory, or vocabulary. For familiar objects, we anticipated that vocabulary would play a more significant role, which was not what was observed. We interpret these results in terms of children's capacity to shift to other dimensions or to re-describe stimuli. Working memory (i.e., keeping track of dimensions) and inhibition (e.g., inhibiting irrelevant salient dimensions) did not reach significance. We also discuss the absence of correlation between vocabulary and the generalization task.