Connecting the tots: Strong looking-pointing correlations in preschoolers' word learning and implications for continuity in language development.

How does one assess developmental change when the measures themselves change with development? Most developmental studies of word learning use either looking (infants) or pointing (preschoolers and older). With little empirical evidence of the relationship between the two measures, developmental change is difficult to assess. This paper analyzes 914 pointing, looking children (451 female, varied ethnicities, 2.5-6.5 years, dates: 2009-2019) in 36 word- or sound-learning experiments with two-alternative test trials. Looking proportions and pointing accuracy correlated strongly (r = .7). Counter to the "looks first" hypothesis, looks were not sensitive to incipient knowledge that pointing missed: when pointing is at chance, looking proportions are also. Results suggest one possible path forward for assessing continuous developmental change. Methodological best practices are discussed.