Does child-mother attachment predict and mediate language and cognitive outcomes? A series of meta-analyses

•Through meta-analyses of 125 studies (N = 9,213 children), this study shows medium-sized associations between child-mother attachment security and child cognition and language.•Additionally, using meta-analytical structural equation modeling, this study shows that both maternal sensitivity and child-mother attachment contribute to child cognitive and language outcomes.•This study helps shed light on the developmental processes by which parenting and early childhood relationships influence cognitive and language development in children. A programmatic set of meta-analyses by Groh et al. (e.g., Groh et al., 2017a) and Madigan et al. (e.g., Madigan et al., 2023) demonstrated that secure child-caregiver attachments are positively associated with children’s social and emotional development, with somewhat stronger associations identified in relation to social competence and (lower) externalizing behaviors than for (lower) internalizing symptoms (Groh et al., 2017a). The association of attachment security with children’s cognitive and language outcomes, however, is relatively less well established. Moreover, it is unknown whether attachment is associated with these outcomes through direct links, indirect links (i.e., as a mediator of the association between caregiver sensitivity and child cognition and language processes), or both. Empirical tests of these hypotheses have not yet been conducted. The current study had two main objectives: 1) provide a meta-analytic update for the association between attachment security and cognition and language (k = 125 studies [107 samples]; N = 9,213 children; 52.5% boys; 100% mothers; 93% from North America/Europe), and 2)test this association within a larger mediation model that accounts for the roles of sensitivity and attachment through a meta-analytic structural equation model (sensitivity → attachment → cognitive and language outcomes). Results showed that child-mother attachment security was significantly associated with child cognition (r = 0.17, 95% CI [0.14, 0.20]) and language outcomes (r = 0.16, 95% CI [0.12, 0.20]). The MASEM model revealed a small, but significant, indirect effect of sensitivity on cognitive and language outcomes through attachment security. The discussion considers the theoretical and practical implications of these findings.