Abstract

Coyne’s (1976) Interpersonal Theory of Depression highlighted the idea that mildly dysphoric individuals exhibit behaviours which further increase their risk of becoming depressed. Keeping Coyne’s framework in mind, the three studies presented in this dissertation were designed to better understand the role of co-rumination and excessive reassurance seeking in the development of gender differences in depressed affect which are observed starting in adolescence (Wichstrom, 1999). These studies were done with a sample of 270 early adolescents who were assessed at five time points across a school year, although data from only the last two time points were used for this particular project. The goal of the first study was to examine the validity and reliability of newly developed peer-nomination items for the measurement of excessive reassurance seeking and co-rumination, to be used in the other two studies. While the two measures were found to be highly related, model fit indices were significantly better when both measures were kept separate. The aim of the second study was to examine the moderating role of excessive reassurance seeking and co-rumination on the longitudinal association between anxiety and depressed affect. Only excessive reassurance seeking was found to moderate that association, and it was found that when combined with high levels of anxiety, depressed affect was found to be higher 6 weeks later. Excessive reassurance seeking on its own, however, was found to predict lower levels of depressed affect. No significant results were found in terms of co-rumination. The aim of the third and last paper was to examine how co-rumination and excessive reassurance seeking moderated the association between depressed affect and both isolation and victimization. It was found that co-rumination moderated the association between depressed affect at T4 and later victimization and isolation. Excessive reassurance seeking, on the other hand, only moderated the association between depressed affect and victimization. Together, this series of studies illustrates the important role of co-rumination and excessive reassurance seeking in the depression cycle.