Does the understanding of complex dynamic events at 10 months predict vocabulary development?

Abstract

By the end of their first year, infants are able to interpret many different types of complex dynamic visual events, such as caused-motion, chasing, and goal-directed action. The present work examined whether there are meaningful individual differences in infants' ability to represent dynamic causal events in visual scenes and whether these differences influence vocabulary development. As part of the longitudinal Language 0-5 Project, 78 10-month-old infants were tested on their ability to interpret three dynamic motion events, involving (a) caused-motion, (b) chasing behaviour, and (c) goal-directed movement. The infants showed evidence of understanding the first two event types, but not the third. Looking behaviour in each task was not meaningfully related to vocabulary development, nor were there any correlations between the tasks. The results of exploratory analyses and simulations further suggested that the infants' understanding of each event may not be predictive of their vocabulary development, and that looking times in these tasks may not be reliably capturing any meaningful individual differences in their knowledge. This raises questions about how to convert experimental group designs to individual differences measures, and how to interpret infant looking time behaviour.

On the Structure and Source of Individual Differences in Toddlers' Comprehension of Transitive Sentences

“…This is increasingly becoming a concern in language acquisition research (Kidd et al, 2018a ; Donnelly and Kidd, 2020 ). For example, in a recent study aimed at examining whether the comprehension of dynamic motion events by 10-month-old children was related to their vocabulary development, Durrant et al ( 2020 ) found that looking times did not reliably capture individual differences. They point out that little is known about the drivers of the attention of children on these sorts of tasks; it may be that the comprehension of children is non-linearly related to looking time.…”