Look at that: Spatial deixis reveals experience-related differences in prediction.

Prediction-based theories posit that interlocutors use prediction to process language efficiently and to coordinate dialogue. The present study evaluated whether listeners can use spatial deixis (i.e., this, that, these, and those) to predict the plurality and proximity of a speaker's upcoming referent. In two eye-tracking experiments with varying referential complexity (N = 168), native English-speaking adults, native English-learning 5-year-olds, and non-native English-learning adults viewed images while listening to sentences with or without informative deictic determiners, e.g., Look at the/this/that/these/those wonderful cookie(s). Results showed that all groups successfully exploited plurality information. However, they varied in using deixis to anticipate the proximity of the referent; specifically, L1 adults showed more robust prediction than L2 adults, and L1 children did not show evidence of prediction. By evaluating listeners with varied language experiences, this investigation helps refine proposed mechanisms of prediction, and suggests that linguistic experience is key to the development of such mechanisms.