Timing pubertaire et adaptation psychosociale à l'adolescence : le rôle des relations interpersonnelles et des vulnérabilités individuelles

The objective of this dissertation was to evaluate the longitudinal links between pubertal timing and internalizing and externalizing problems during adolescence. Within a theoretical framework of biosocial interactions and the vulnerability-stress model, the moderating effect of social environments and preexisting individual vulnerabilities was examined. Two empirical studies investigated the links between pubertal timing and conduct problems and between pubertal timing and depressive symptoms. It was expected that early or off-time puberty would be associated with conduct problems and depressive symptoms, but that this link would be intensified in risky social and interpersonal contexts and if paired with prepubertal individual vulnerabilities. These hypotheses were tested using data from the National Longitudinal Survey of Children and Youth (NLSCY), a representative biennial survey of Canadian children and adolescents managed by Statistics Canada. Measures analyzed in this dissertation were collected at 10–11 years old, 12–13 years old, 14–15 years old and 16–17 years old through questionnaires and interviews with adolescents and their parents.   The goal of the first empirical article of this dissertation was to evaluate whether the interactions between pubertal timing and characteristics of peer context, namely deviant peer affiliation and romantic experience in early adolescence, predicted physically aggressive and non-physically aggressive conduct problems two years later. A significant interaction between pubertal timing and deviant peer affiliation was found, suggesting that early puberty was associated with higher frequencies of physically aggressive conduct problems only in the context of deviant peer affiliation. Therefore, among adolescents who affiliated with deviant peers in early adolescence, early maturing adolescents were more prone to report higher frequencies of physically aggressive conduct problems than on-time or late maturers. A significant interaction also emerged for girls’ non-physically aggressive conduct problems, as early pubertal timing was associated with non-physically aggressive conduct problems only in the context of romantic experience. Indeed, when adolescent girls reported romantic experience, early maturers showed more non-physically aggressive conduct problems than their peers.  The second article of this dissertation investigated the moderating role of individual vulnerabilities to depression (emotional problems in late childhood), peer factors (deviant peer affiliation, early romantic dating and perceived peer popularity) and parental factors (perceived parental rejection) in the association between pubertal timing and depressive symptoms in adolescence. For adolescent girls, early puberty was associated with more depressive symptoms only in girls who combined emotional problems in late childhood and early dating experience. For adolescent boys, early and late pubertal timing was related to depressive symptoms, but only in those who had previously experienced emotional problems in late childhood. Early pubertal timing was also linked to depressive symptoms in the context of deviant peer affiliation (boys) and in the presence of higher levels of perceived parental rejection (boys and girls).  In sum, the significant interactions found between pubertal timing, characteristics of social context, and individual vulnerabilities bring theoretical and practical considerations. Firstly, these results suggested that pubertal timing is not a risk factor per se of internalizing and externalizing problems in adolescence. These findings underscored the importance of taking into account the social environments and individual risk factors prior to puberty in order to better understand the impact of pubertal transition on adolescents’ psychosocial adjustment.

Keyphrases: Adolescence, Pubertal timing, Adolescent development, Conduct problems, Depression, Deviant peer affiliation, Romantic experience, Parent-adolescent relationships