Individual differences in adolescents' behavioral and emotional problems: a person centered approach

Adolescence is a period characterized by many developmental demands, changes and tasks to be achieved (Steinberg & Morris, 2001; Zahn-Waxler et al, 2000). During this period adolescents may experience increase in internalizing (e.g., social withdrawal, psychosomatic reactions, anxiety, or depression) and externalizing problems (e.g., aggressive and rule breaking behavior;Zahn- Waxler, Shirtcliff, & Marceau, 2008). In particular, internalizing problems, such as anxiety or depression, tend to be frequently experienced across adolescence and young adulthood, to co-occur, and overall tend to jeopardize adolescents’ development overtime, because they are often associated with several mental health problems (e.g., Chavira et al., 2004; Cummings et al 2014; Weissman et al., 1999; Zahn-Waxler et al., 2000). . A large body of research support the role of personality individual differences (temperamental characteristics and personality traits) in predicting emotional and behavioral problems (e.g., Krueger & Tackett, 2003; Tackett, 2006; Maher & Maher, 1994; Castellani et al., 2014; Thartori et al., 2018; Klimstra et al., 2010). One of the models that gained more consensus for explaining those associations is the Vulnerability model (Tackett, 2006), suggesting that specific temperamental or personality characteristics may increase or decrease individual’s vulnerability to incur in specific psychopathological tendencies, and affect the severity and the maintenance of psychopathological problems. In this dissertation, we conceived personality and temperamental characteristic as two facets (interconnected) of individual differences (McCrae et al., 2000; Caspi, Roberts & Shiner, 2005; Matthews, 2009). As reported by Rothbart & Bates, temperament represents the affective, activational, and attentional core of personality, whereas personality includes thoughts, skills, habits, values, morals, beliefs, etc. (Rothbart & Bates, 2006). Personality traits represent specific patterns of “thoughts, emotion, and behavior that show consistency across situations and stability overtime”, whereas temperamental traits are “limited to basic processes of reactivity and self-regulation, and do not include the specific content of thought” (Rothbart & Bates, 2006; p. 100). An holistic approach to the study of adolescents’ individual differences and maladjustment. In the present dissertation, we addressed global functioning and individual differences development according to the Person-centered approach (Magnusson, 2003; Bergman, Magnusson, & El-Khouri, 2002). This approach emphasized a holistic- interactionistic view of developmental processes, and underline the importance of “classify” individual patterns of functioning into several, finite, number of specific patterns, in order to understand the overall structure of personality or temperament (Caspi, Roberts, & Shiner, 2005; Asendorpf, 2006; 2013). Previous findings supported the role of personality in predicting adolescents’ emotional and behavioral problems (Klimstra, Akse, Hale, Raaijmakers, & Meeus, 2010). In the last 30 years, within a person-centered approach, adopting the Big Five model (McCrae & Costa, 1995), many researchers found a structure of personality profiles characterized by three profiles (e.g.; Asendorpf & Van Aken, 1999; Meeus et al., 2011; Robins et al., 1996): the Resilient profile, characterized by high levels of all the personality traits (i.e., Extraversion, Agreeableness, Conscientiousness, Emotional Stability, and Openness); the Overcontrolled profile, characterized by low levels of Extraversion and Emotional Stability and high levels of Conscientiousness; and the Undercontrolled profile, characterized by low levels of Emotional Stability and Conscientiousness, and high levels of Extraversion. These personality profiles showed specific associations with maladjustment: in particular, Resilient is generally a well-adapted profile; in contrast, Undercontrollers tend to manifest aggressive and transgressive behaviors, whereas Overcontrollers tend to experience anxious and depressive feelings (e.g., Asendorpf & Van Aken, 1999; Akse et al., 2004; 2007). With regard to temperament, a large body of research focused on how some temperamental factors, such as negative emotionality and self-regulation, can predict maladjustment. In particular, the combined predictive value of negative emotionality and self-regulation in the development of internalizing problems was confirmed (e.g., Eisenberg & Morris, 2002; Rothbart & Bates, 2006; Zhou et al. 2007; Eisenberg et al., 2009; Laible et al, 2014, Eisenberg & Fabes 1992 e 2006): high negative emotionality associated to low self-regulation predicted later higher internalizing problems, whereas high negative emotionality associated to average levels of self-regulation predicted later average levels of internalizing problems in children and adolescents. Those findings highlighted the importance to consider, beyond the unique predictive value of temperamental factors in the development of internalizing problems, also how they interact each other (e.g., Rettew et al., 2008; Vervoort et al., 2011). However, to our knowledge, there are no studies focused specifically on adolescents’ temperamental profiles (including negative emotionality and self-regulation) and on their relations with anxious and depressive trajectories during the transition from early to middle adolescence. Most of the existing studies focused on young childhood (e.g., Laible et al., 2010), or they focused on temperamental dimensions more related to biological and cognitive systems (i.e., like novelty seeking, harm avoidance, persistence, reward dependence; Rettew et al., 2008).