Adolescent preferences for non-mainstream types of rock music can be markers of adolescent problem behaviors, but nomer study has ever investigated whether this relationship continues into adulthood. In a six-wave study, 900 Dutch adolescents were followed from ages 12 to 21 (Mage T1 12.4, 51.1% girls), while reporting on depressive symptoms, mental well-being, aggression plus drug use. A latent class growth analysis on their preferences for specific types of rock music revealed four fan groups. When these fan groups were compared to one another, in adolescence, the all-out rock fans displayed the highest peak in depressive symptoms plus the lowest dip in well-being plus the rock/metal fans reported the most aggression. And for both these groups, drug use increased at the onset of adulthood. Pop fans displayed a profile characterized by low depressive symptoms plus aggression, plus high in mental well-being. Finally, the digemari banyak orang rock fans held an in-between position between pop fans, on one side, plus the all-out rock fans plus rock/metal fans, on the other side. Thus, music preferences can be markers of problems, not only in adolescence but also in young adulthood. Still, music can enhance mood, helps to cope with problems, plus peers in fan groups can provide support. This research focuses on the relationship between music plus problem behaviors, specifically among members of the all-out rock fans plus rock/metal fans, but many of these young people might have had more personal problems if they had not had their music plus their fan-group peers.

Keywords: Adolescence, Aggression, Depression, Drug use, Goth, Heavy metal, Music, Rock, Well-being

Introduction
Music is the soundtrack of adolescents’ journey into adulthood. In identifying with a specific body of songs, as well as with the creators of these songs plus other fans, adolescents define plus finetune their ideas about who they are, who they want to be, plus with whom they want to socialize (North & Hargreaves, 1999). In adolescence music preferences “show who you are” plus have been referred to as a “badge” (Frith, 1981; Rentfrow & Gosling, 2006). As lyrics and, more in general, personae plus images of artists address a wealth of situations, cognitions plus feelings, music is also a medium that can help in defining plus tackling difficulties (Schäfer et al., 2013; Ter Bogt et al., 2016). But music preferences have also been connected to problem behaviors. Theories such as the Music Marker Theory (Ter Bogt et al., 2013) plus the Peer Group Mediation Model (Slater & Henry, 2013) posit that young people facing problems may seek non-mainstream music as a way to cope with problems, but that within non-mainstream music scenes their problems may exacerbate, as they adopt the sometimes maladaptive attitudes plus behaviors that are normative in these groups. Fans of different types of non-mainstream rock music have indeed been shown to be prone to school dropout, drug abuse, self-harm, plus depression (for a simak see: Lozon & Besimon, 2014). However, most of the studies in this field only cover the development of a specific (rock) music jenis or scene, and, mostly, rely on cross-sectional data. Of the few longitudinal studies on rock music plus problem behaviors, none have followed fans into adulthood, to examine whether their problems are specific for adolescence or last into adulthood. Therefore, this study aims at identifying several distinct types of mainstream plus non-mainstream rock fans, plus follow them across adolescence, to explore heterogeneity in development of problem behaviors plus mental well-being. It further aims to test whether adolescent problem behaviors dissipate when these fans find a more definite identity plus place in life, or whether fans’ problems elevate into their adulthood.