Uncovering cognitive and metacognitive factors that influence onset of adolescent depression

Evidence from the World Health Organisation's World Mental Health surveys shows that about half of all lifetime mental illness starts by the time patients reach their mid-teens and three-quarters by the mid-20s (WHO, 2001; Kessler et al., 2008). During my research programme, I aim to explore the cognitive mechanisms underlying development of low self-esteem, which has been shown to predict onset of a depressive episode in prior longitudinal studies (Sowislo and Orth, 2013). My research proposal relies on two (perhaps not entirely distinct) constructs: metacognition, thinking about one's own thinking, and mentalising, thinking about others' thinking. These constructs are relevant to self-esteem because creating a concept of the self may rely on, firstly, abstractions from memory about previous reactions to and decisions about past events and experiences (utilising metacognition) and, secondly, appraisals about what others' think of us (utilising mentalising; Sebastian et al., 2008). I aim to investigate the development of these constructs using various cognitive tasks, utilizing longitudinal designs. I will also measure depressive symptoms, with a particular focus on measures of self-worth and self-esteem. With this, I aim to develop our understanding of how individual differences in metacognitive insight, mentalising and sensitivity to negative social feedback may predict onset of depression during adolescence.