Broadening Views on Adolescents’ Personalities: Investigating Construct Clarity, Intertwined Developments, and (Mal)adjustment

Abstract

Adolescence is characterized by profound biological, psychological, and social changes that come with increased opportunities for personal growth but also potential vulnerabilities. Against this backdrop, different personality characteristics and their developments may provide valuable insights into how adolescents differ in their adjustment to these changes. People’s personalities—the entirety of characteristics that make up someone’s style of thinking, feeling, and behaving—have long been recognized as a key factor in understanding human development and functioning. Over the years, most researchers have adopted a dynamic perspective, viewing personality as a complex, evolving system that is not only influenced by genetic and environmental influences but is also inherently shaped by interactions among its components. This perspective raises important questions about how personality is organized, how different personality characteristics develop compared to and in relation to one another, and how they might complement each other in contributing to people’s psychosocial (mal)adjustment. Given that adolescence is a central period of personality (re-)organization, it provides a unique developmental context to investigate these questions. Building on theoretical considerations from the fields of developmental, personality, and clinical psychology and integrating them under three overarching principles from lifespan psychology, this dissertation aimed to explore how the simultaneous consideration of different personality characteristics informs three global research aims: First, to increase our understanding of less established personality characteristics by localizing them in the nomological network of other, more widely studied characteristics (multidimensionality). Second, to investigate the developments of different personality characteristics on their own and in relation to each other (multidirectionality). And third, to assess how personality characteristics might complement each other in their predictive effects on psychosocial (mal)adjustment across different life domains (multifunctionality). To address these aims, this cumulative dissertation comprises three preregistered studies, drawing on data from four adolescent samples (individuals aged between 14 and the early twenties) that provide insights into the development of three groups of personality characteristics and different indicators of psychosocial (mal)adjustment. All studies focused on one of the following personality characteristics or a combination of them: The Big Five personality traits, general self-esteem, or multidimensional perfectionism. Aiming for construct clarity of a newly proposed conceptualization of perfectionistic strivings, Study I focused on the nomological networks of striving toward perfection vs. excellence in adolescence. Using structural equation modeling, this study investigated differential cross-sectional associations of striving toward perfection vs. excellence with the Big Five traits and self-esteem. Study II focused on the intertwined developments among personality characteristics, specifically between each Big Five trait and self-esteem, while also examining their respective interindividual stabilities. I used continuous time modeling to investigate rank-order stabilities and the developmental interplay between each Big Five trait with self-esteem in a time-sensitive manner. Further, this study extended rater-perspectives and compared results from adolescents’ personality self-reports to results derived from other-reports. Finally, Study III adopted a longitudinal perspective on striving toward perfection vs. excellence, using latent-growth curve modeling and cross-lagged panel modeling, to examine stability and change of the different strivings and investigate their longitudinal interplays with indicators of psychosocial maladjustment across three central life domains (i.e., school, social relationships, and mental health). Moreover, this study aimed to investigate potential mediating processes within these interplays by considering the role of perfectionistic concerns. Together, the three studies offer nuanced insights into the development and functioning of adolescents’ personalities. The findings support the conceptual distinction between striving toward perfection and striving toward excellence and demonstrate their differential associations with the Big Five and self-esteem. Further, personality characteristics exhibit moderate to high rank-order stability during adolescence, yet also change and interact in meaningful, temporally sensitive ways. Specifically, reciprocal associations were found between certain Big Five traits and adolescents’ self-esteem, underscoring the dynamic interplay of different personality characteristics during this time of life. Finally, no longitudinal effects of striving toward perfection or excellence across different indicators of psychosocial maladjustment were observed. Theoretically, the key findings from this dissertation extend the multidimensional, multidirectional, and multifunctional principles of lifespan psychology by specifying how specific personality characteristics develop and function during adolescence. This dissertation further emphasizes the need to incorporate (developmental) timing and the intertwinement of personality characteristics to broaden our understanding of personality in adolescent (mal)adjustment. Methodologically, the use of continuous time modeling and multi-informant data highlights the value of fine-grained, temporally sensitive, and cross-perspective approaches. Future research should integrate multiscale, person-centered designs to explore how short-term personality dynamics accumulate into long-term developmental outcomes.