Social and individual factors modulate parent-infant interactions: Lessons from free play sessions in an Argentine sample

•SES positively contribute to coordinated joint engagement.•SES negatively contribute to infant passive observation.•Negative emotionality correlated with increased duration of unengaged behavior.•Higher SES positively associated with surgency. In this study, we aimed to explore the associations between socioeconomic status (SES) (i.e., parents’ education and occupation, quality of the home and overcrowding), temperament styles (i.e., surgency, negative emotionality and regulatory capacity) and early dyadic and triadic nonverbal communication behaviors. We recruited 60 mother-infant dyads (mean age: 10.89 months, range: 9–13 months) low-to-mid SES, and assessed the duration of their communication behaviors using the Bakeman and Adamson (1984); SES was measured using INDEC Scale (2001), and temperament was assessed using the Infant Behavior Questionnaire-Revised Very Short Form (IBQ-R VSF, Putnam et al., 2014). Results showed that SES and their subdimensions were positively associated with passive, coordinated joint engagement (coordinated attention to person and object) and surgency, and negative with infant passive observation. Also, there were positive correlations between negative emotionality and unengaged attention behavior. We conclude that SES contributed to parent-infant interactions and temperament style from early months of life. We interpret these findings in relation to early intervention approaches aimed at promoting cognitive and social development.