Development of Social-Cognitive Abilities in the First Two Years of Life

Abstract

Infants develop important social cognitive abilities in the first year of life. Interaction changes from dyadic to triadic and infants start to understand goal-directed and communicative actions. However, different theories and findings exist about the emergence of early social cognitive abilities and to date there is little systematic comparison and longitudinal evidence. Some argue that action understanding and communicative understanding are present from birth and emerge early on in behavior (6-months-olds) as separate systems. In contrast, others suggest that infants develop an integrated understanding of humans as goal-directed and perceiving organisms through second-person interaction around their first birthday. While some paradigms assess infants as observers of social situations, other paradigms directly involve infants as interactants in social situations. The aim of this thesis is (1) to systematically compare social cognitive abilities in different situations and age groups (Study 1 & Study 2) and (2) to examine stable manifestations and developmental relations of action understanding and communicative understanding (Study 3). In Study 1 + Study 2, I used a cueing paradigm with a centrally presented person looking behind one of two barriers to test visual-perspective-taking (VPT) in communicative vs. non-communicative situations. To measure reflective VPT ability in contrast to reflexive spatial cueing, the cue was presented for a long time (3000ms). Infants looking time to the cued barrier revealing an empty box was used as indication for object expectation. Results of Study 1 revealed that 14-months-olds need communicative cues to represent what others can see. At the age of three years, VPT seems to be automatized to non-communicative cues similar to adults. In Study 2, only weak VPT was found for younger infants (8-months-olds). Results speak for the emergence of social cognitive abilities later in development. In Study 3, I measured action understanding and communicative understanding in interaction-based and eye-tracking paradigms using a longitudinal design. Results indicate an emergence of stable abilities at 11 months. Relations between action understanding and communicative understanding is in support of the hypothesis that they are part of one integrated understanding of humans. Method comparisons revealed earlier competencies in interaction-based measures than in eye-tracking, supporting the assumption that infants develop an understanding through second-person interaction. Together, results support the view that infants’ social cognitive skills emerge at the end of the first year of life, instead of a present competence from early on. This understanding emerges through and first reveals itself in communicative interactions. Future research should focus on social-interactional experiences as predictors of intraindividually stable, emerging social cognition at the end of the first year of life.