The social self: Categorisation of family members examined through the self-bias effect in new mothers

Self-concept is the basis for many cognitive and behavioural processes, such as the processing of self-related information (e.g. one’s own face, one’s own name) and the categorisation of people into various social groups (e.g. self vs. other, family vs. non-family). Previous research suggests that one’s self-concept is not only construed from individual characteristics but also from one’s social experiences and group memberships. Thus, important life experiences such as childbirth and becoming a parent have significant impacts on one’s self-concept and subsequently influence the categorisation of information regarding the self and others. In two experiments, women who gave birth within the last 2 years were recruited and tested on a series of categorisation tasks using names (Experiment 1) or faces (Experiment 2) as stimuli. Results consistently revealed faster reaction times in response to the self regardless of stimulus type (name or face) and response category (self vs. other, family vs. non-family, familiar vs. non-familiar). A family bias for one’s own baby name and one’s own mother name over friend was observed in the family versus non-family but not in the familiar versus non-familiar categorisation tasks. These findings indicate that information regarding the self and one’s family members receives preferential processing in social categorisation. These findings contribute to current understandings of the evolving self-concept through social experiences and its influence on group membership categorisations and response behaviour. © Experimental Psychology Society 2025.