Infants expect friends, but not rivals, to be happy for each other when they succeed

Abstract

Emotions arise not just from people’s own circumstances, but also from the experiences of friends and rivals. Here we asked if human infants have expectations about vicarious emotions, and if they expect those emotions to be guided by social relationships. Ten- and 11-month-old infants (N=154) expected an observer to be happy rather than sad when the observer watched a friend successfully jump over a wall. In contrast, infants did not expect the observer to be happy when the friend failed, nor when a different, rival jumper succeeded. Infants are thus able to integrate information about desires and outcomes with knowledge of social relationships to infer others’ vicarious emotional responses. Biased concern for friends but not adversaries is not just a descriptive feature of human relationships, but an expectation about the social world present from early in development.

Preverbal infants’ understanding of social norms

“…Infants discriminate positive and negative facial expressions towards the end of their second year of life 45 . Likewise, previous studies demonstrated that actions of moving towards each other 13 as well as facial expressions 46 are also differentiated by infants (and elicit meaningful effects on measures of pupil dilation 25 ) for geometrically shaped characters. In addition, while former studies used explicit verbal expressions of praise and admonishment 47 here we created novel sounds to support the characters approval or disapproval.…”

Dyads in networks: We (dis)like our partners' partners based on their anticipated indirect effects on us

“…Rivals hinder our access to resources, including partners and status (Buss et al, 2000;Duntley & Buss, 2011;Hilbe et al, 2018). Correspondingly, people's attitudes toward others appear to match the probable effects that others will have on their welfare: People value and like those who have a stake in their welfare or that of their kin (Lewis et al, 2015;Smith-Flores et al, 2024;Sznycer et al, 2019); people disvalue and dislike competitors, rivals, and enemies (Adams, 2005;Holt, 1989;Wiseman & Duck, 1995). But people's dyadic interactions with their associates-friends, spouses, rivals-do not take place in a social vacuum.…”