Adolescents may be particularly vulnerable to depression. Yet Public health nurses working with large groups of adolescents are often unable to recognize depressed youths due to the lack of simple, reliable screening tools. This exploratory study was undertaken in order to gain information that could be used to develop such a tool. Specifically, the following question was posed: 'Are there modes of relating interpersonally that can be used to distinguish the highly and moderately depressed adolescent from the non-depressed adolescent?' The answer was sought from information obtained from adolescent self-reports on Beck's Depression Inventory and an adapted and pre-tested form of McNair and Lorr's Interpersonal Behavior Inventory. These inventories were administered to twenty-five adolescents who attended a treatment centre for adolescents with emotional problems and seventy seven randomly selected adolescents who attended four Catholic high schools in Greater Vancouver. Adolescents were classified as non-depressed, moderately depressed and highly depressed on the basis of their scores on Beck's Depression Inventory. An analysis of variance was carried out to discover if there was a significant difference in interpersonal behavior scores of non-depressed, moderately depressed and highly depressed adolescents. A simple regression analysis and a multiple step-wise regression analysis was done to see if there was a significant correlation between any interpersonal behavior categories that could distinguish between the non-depressed, moderately depressed, and highly depressed adolescent. The findings supported the overall conclusion: adolescents who exhibit mistrust, competition and detachment most of the time or all of the time and exhibit dominance only some of the time or not all all, may be moderately or highly depressed adolescents. The findings did not support the generally held thesis that suppressed hostility is an important factor in the depressed person. / Applied Science, Faculty of / Nursing, School of / Graduate

Background: Attachment theory [Bowlby, J. 1969, 1973, 1980 Attachment & Loss, Volumes I-III, London: Hogarth Press] proposes that a person’s experiences of care in infancy and childhood lay the foundations for their internal working models of themselves and others. Inconsistent, unpredictable or hostile caregiving can lead individuals to hold negative internal working models which can impact on their mental health later in life. Many looked after and accommodated young people have experienced this type of neglectful or abusive parenting. These experiences of parenting may lead looked after young people to have internal working models of themselves as ineffective and of others as powerful, thus leading them to develop a learned helplessness and a more external locus of control. Objectives: A systematic review was carried out in order to explore the mechanisms by which the relationship between attachment and depression functions in adolescence. An empirical study aimed to investigate whether young people with negative attachment experiences, those who are looked after and accommodated, have higher levels of depression or a more external locus of control than other young people of the same age and the role these play in their future thinking. Method: Nineteen papers investigating mediators and moderators of the attachmentdepression relationship in adolescence were reviewed. In the empirical study, a group of looked after and a group of non-looked after young people aged 15-18 were asked about their approach and avoidance goals for the future and were asked to rate beliefs in their control over, and likelihood of, achieving these goals. Results: Evidence was found for a number of mediators of the relationship between attachment and adolescent depression. There were also found to be significant differences between the two groups with differing care histories with regards to levels of depression and locus of control, with looked after young people having higher levels of depression and a more external locus of control. A mediation analysis found that locus of control mediated the relationship between looked after status and future thinking. Conclusions: A person’s attachment history and experiences of care in early childhood can impact on their levels of depression and locus of control. There are a number of factors which mediate or moderate the attachment-depression relationship, most of which can be attributed to an individual’s internal working model of either themselves or others. Locus of control plays a critical role in young people’s future thinking and professionals working with accommodated adolescents should facilitate these young people to have experiences which will help to increase the internality of their locus of control. Objective: Attachment security has been found to be a significant predictor of depression in adolescence. This review aimed to examine the pathways by which this relationship functions by reviewing studies which have investigated potential mediating or moderating factors. Method: Studies were included if they investigated mediation and/or moderation of the relationship between attachment and adolescent depression. Results: A number of cognitive and social factors were found to mediate the attachmentdepression relationship. Age was found to be a significant moderator of the relationship but the findings on gender were inconsistent. The findings should be treated with caution, however, as many of the studies reviewed were potentially underpowered. Conclusions: A model is proposed in which mediating factors were linked to the internal working models of self and others. The need for future research to be carried out in clinical adolescent populations with sample sizes large enough to ensure adequate power was identified.

In contemporary society, online Social Networking Sites (SNS) such as Facebook provide increasingly popular contexts within which late adolescent peer interactions and accompanying identity experiments can occur. Consequently, of increasing interest is exploring the impact of SNS use on psychological functioning in this age group. There is some evidence suggestive of a relationship between greater SNS use and increased depressive symptoms. However, findings are inconsistent, with a large body of literature also indicative of possible beneficial effects of SNS use on adolescent social and emotional adjustment. Therefore, as a means to address this divergence, the present study aims to investigate whether it is the quantity of use, including use of the site to connect with existing or new contacts, or the quality of Facebook interactions that might relate to depressive symptoms. Moreover, the present research attempts to identify for which late adolescents these associations are more likely to be a risk, drawing on constructs implicated in offline self-definition and identity development. One hundred and sixty-nine late adolescents (mean age 18.6 years) participated in this quantitative, cross-sectional study. Participants completed an online survey comprising self-report questionnaires validated by previous research assessing depressive symptoms, the intensity of Facebook use, strategy used to connect with peers on Facebook, self-reported quality of interactions on Facebook, and self-definition and identity variables; self-concept clarity (SCC), separation-individuation, and ego-identity commitment. Consistent with previous research, no relationship was found between the intensity of Facebook use, including number of Facebook friends, time spent on the site each day, perceived integration of the platform into daily life, and connection strategy and depressive symptoms. There was, however, evidence suggestive of a relationship between reports of feeling down following interactions on Facebook and increased depressive symptoms. Self-definition and identity variables were not found to moderate this relationship.

Adolescent depression is a major public health problem, which is associated with educational problems, long-term psychiatric illness and suicide. One major source of stress during adolescence is peer rejection. In this thesis, I investigate the nature of the relationship between peer rejection and adolescent depression. In a review of longitudinal and experimental studies, I describe a bi-directional relationship between peer rejection and depressive symptoms. I then outline how genetic, cognitive and neural vulnerability may modify the effects of peer rejection on adolescent depression. Finally, I introduce five empirical chapters which test these hypotheses using different methodological approaches. The first study is a molecular genetic analysis of a sample of adolescents with and without a diagnosis of mood disorder. I report an interaction between diagnostic group, environmental stress (though not peer rejection specifically) and 5HTTLPR genotype on symptoms of anxiety, which supports the role of genetic factors in modifying the relationship between environmental stress and adolescent mood disorder. The second study is a behavioural study of negative attention biases in a typically developing sample of adolescents. I report a negative attention bias in adolescents with low (versus high) self-esteem. Although the data do not support a causal role for attention biases in adolescent depression, such biased cognitions could also moderate responses to peer rejection, maintaining affective symptoms. A final set of three fMRI datasets investigates how neural circuitry may influence depressed adolescents’ responses to peer rejection at three distinct stages: i) expectation of peer feedback, ii) the receipt of peer rejection, iii) emotion regulation of peer rejection. Data show distinct behavioural and neural differences between depressed patients and healthy controls during expectation and reappraisal of peer rejection, although heightened emotional reactivity immediately following the receipt of peer rejection did not differentiate behavioural or neural responses in adolescents with and without depression.