Daily ups and downs in adolescents' depressive symptoms: The role of daily self-criticism, dependency and basic psychological needs.

INTRODUCTION: Although associations between Blatt's personality dimensions of self-criticism and dependency and adolescents' depressive symptoms are well-established, only few studies have examined associations between these variables at the level of daily, within-person fluctuations. Moreover, our understanding of the mechanisms underlying this personality vulnerability to depressive symptoms is limited. Therefore, we studied (a) daily fluctuations in both personality and depressive symptoms over a 7-day period and (b) the possible interplay between daily variations in personality vulnerability, need-based experiences (as conceptualized in Self-Determination Theory), and depressive symptoms. This interplay was examined in terms of both a mediational and a moderating role of the need-based experiences. METHODS: Participants were 121 Belgian adolescents (Mage = 15.81; SDage = 1.50; 52 % male) who completed questionnaires tapping into daily self-criticism, dependency, need-based experiences, and depressive symptoms every evening during seven consecutive days. RESULTS & CONCLUSIONS: Multilevel analysis revealed that self-criticism and dependency fluctuated substantially on a daily basis. These daily fluctuations in personality were related to daily fluctuations in depressive symptoms, with daily variation in need-based experiences mediating these associations. We found no evidence for interactions between personality and the need-based experiences. The findings underscore the importance of considering daily fluctuations in individuals' personality vulnerability and point to the explanatory role of need-based experiences in the relation between personality and depressive symptoms on a daily basis.

Toward a Better Understanding of the Reciprocal Relations Between Adolescent Psychological Need Experiences and Sleep.

In two diary studies, we examined the reciprocal daily association between the satisfaction and frustration of adolescents' basic psychological needs and sleep, and the role of stress and fatigue in these associations. In Study 1 (N = 211; 52% female; Mage = 15.86 years, SD = 1.18 years), daily need experiences were unrelated to daily fluctuations in subjective sleep outcomes. However, shorter daily sleep quantity was related to higher daily fatigue, which in turn related to more daily need frustration and less need satisfaction. Study 2 (N = 51; 49% female; Mage = 15.88 years, SD = 2.88 years) extended these findings by demonstrating that daily need frustration related to shorter objective sleep quantity and longer wake after sleep onset, indirectly through higher symptoms of stress. Poor sleep quality also related to worse need experiences via higher daily fatigue. These findings underscore the dynamic interplay between daily need experiences and adolescent sleep.

A longitudinal examination of the interplay between personality vulnerability and need-based experiences in adolescents' depressive symptoms.

OBJECTIVE: This study aimed to examine the interplay between the personality vulnerability dimensions of self-criticism and dependency and experienced satisfaction or frustration of the basic psychological needs in relation to adolescents' depressive symptoms. In doing so, we investigated both indirect associations between personality and depressive symptoms (through need-based experiences) and interactions between personality and need-based experiences (i.e., moderation). METHOD: A total of 149 adolescents (52% female, Mage  = 15.20 years at initial assessment, SD = 3.09) participated in this three-wave longitudinal study with 6-month intervals. At each wave, adolescents reported on their personality, need-based experiences, and depressive symptoms. RESULTS: Multilevel analyses showed that dependency and self-criticism related to experiences of need frustration and depressive symptoms at both the between-person level (i.e., the level of interindividual differences) and the within-person level (i.e., the level of intraindividual change). In turn, need frustration was related to adolescents' depressive symptoms at both levels of analysis. Personality did not significantly moderate the associations between the psychological needs and depressive symptoms. CONCLUSION: The results suggest that self-criticism and dependency are related to experiences of psychological need frustration and depressive symptoms at the level of both interindividual differences and within person-change.