All languages have demonstratives—grammatical words like ‘this' and ‘that' in English, which are a universal tool to establish joint attention on a referent. Demonstratives are acquired early, but their mature use has a protracted development, with recent studies showing that 10- and 11-year-old children do not yet use demonstratives like adults do. Here we investigated demonstrative use by teenagers (ages 12-17) and adults with a focus on two social parameters affecting demonstrative choice in Spanish: Listener Position and Listener Attention. The results of two experiments using an online demonstrative-choice task revealed that teenagers use Spanish demonstratives comparably to adults in most conditions. However, teenagers seem to still be adjusting the relative weight of the social parameters affecting demonstrative choice in Spanish, supporting the view that acquiring and regularly using demonstratives trains social cognition through communicative interaction.

In two eye-tracking pilots during reading, we investigated real-time processing of formality-register congruence and subject-verb morphosyntactic congruence, and their relation. Participants read, in German, two context sentences conveying a formal or informal situation, followed by a target sentence containing a high- or low-register verb (e.g., Engl. transl. "The policeman detained the activist" vs. "The policeman grabbed the activist") which matched or mismatched context formality. The second pilot additionally manipulated subject-verb morphosyntactic congruence (e.g., Engl. transl. "*The policeman detain the activist"; "*The policeman grabbed the activist"). We observed main effects of formality-register and morphosyntactic congruence on verb reading times, as well as an interaction effect at the post-verbal object noun. Higher degrees of context and target sentence formality resulted in longer reading times. Ongoing investigation will further clarify our pilot findings, which suggest some interference between formality-register and morphosyntactic congruence processing.