The aim of the study was to examine associations between life events and self-assessed loneliness in adolescence. We used data from a Norwegian population-based twin sample including seven birth cohorts (N = 2,879, 56% females). The participants completed self-report questionnaires three times throughout adolescence, with 2 years in between (i.e.,…

Loneliness becomes more prevalent as youth transition from childhood into adolescence. A key underlying process may be the puberty-related increase in biological stress reactivity, which can alter social behavior and elicit conflict or social withdrawal (fight-or-flight behaviors) in some youth, but increase prosocial (tend-and-befriend) responses…

Schools start early in the morning all over the world, contrasting with adolescents' late chronotype. Interestingly, lower academic performance (i.e. grades or qualifications) was associated with later chronotypes. However, it is unclear whether it is a direct effect of chronotype or because students attend school too early to perform at their…

This handbook offers comprehensive coverage of the topics that are relevant to the field of adolescent and young adult development. The "APA Handbook of Adolescent and Young Adult Development" reviews the many factors that impact youth development across varying themes including biological underpinnings, cognitive and emotive processes,…

Using alcohol, cigarettes, and marijuana during adolescence is associated with risks, yet there is no single cause for adolescent substance use. The etiology of substance use develops over time, across multiple levels of influence. Informed by developmental perspectives, in this review, we provide an overview of biological (e.g., genetic,…

This longitudinal, within-subjects study examined whether adolescents' biological sensitivity to socioeconomic status (SES) for emerging social difficulties varied day to day. Diverse adolescents (N = 315; ages 11-18; 57% female; 25% Asian, 18% Latinx, 11% Black) provided daily diaries and saliva samples for 4 days. We measured biological…

Cognitive science is an interdisciplinary field of researchers from psychology, neuroscience, linguistics, philosophy, computer science, and anthropology who seek to understand the mind. This paper considers findings from this field that are strong and clear enough to merit classroom application. Although many teachers and parents worry that high…

Growth, maturation, and development dominate the daily lives of children and adolescents for approximately the first 2 decades of life. Growth and maturation are biological processes, while development is largely a behavioral process. The 3 processes occur simultaneously and interact. They can be influenced by physical activity and also can…

Cognition, memory, safety, mental health, and weight are all affected by inadequate sleep. Biological studies indicate significant changes in sleep architecture during adolescence, such as changes in melatonin secretion, and a need for greater total sleep time. Yet, social contexts and cultural values impinge on these changing biological sleep…

Biology and the particular gun culture of the United States come together to explain the persistent and powerful attraction of American boys to both real guns and toy guns. The 1990s saw adults begin to conflate "the gun problem" with "the boy problem," sparking attempts (largely failed) to banish toy guns from homes and…

While both positive and negative peer interactions have long been a focus of scientific interest, much less attention has been given to children who tend to refrain from interacting with peers. This volume brings together leading authorities to review progress in understanding the development, causes, and consequences of shyness and social…

The authors review research on risk factors for eating disorders, restricting their focus to studies in which clear precedence of the hypothesized risk factor over onset of the disorder is established. They illustrate how studies of sociocultural risk factors and biological factors have progressed on parallel tracks and propose that major advances…

How children experience, express, and regulate distress has important implications for adjustment. Factors influencing individual differences in these aspects of affective behavior include temperament, context of situation, and parents, to name a few. Gender differences in the expression of affective behaviors have also been implicated in past…

Girls who are overweight tend to perform poorly in mild athletic activities. (CK)

Although boys engage in more delinquent and criminal acts than do girls, female delinquency is on the rise. In 1980, boys were four times as likely as girls to be arrested; today they are only twice as likely to be arrested. In this article, the author explores how the juvenile justice system is and should be responding to the adolescent female…