Adolescence is a period of rapid physical, psychological and social development. Approximately 75% of mental illnesses emerge during this period [1] with many persisting into adulthood, producing significant long-term consequences for an individual’s social adjustment, physical health, overall functioning (e.g. sleep), and quality of life [2]. In the UK, 1 in 6 adolescents (aged 11-16) have been identified as having a probable mental illness – a figure which has steadily increased in the past decade [3]. While the exact reasons for this increase are still uncertain, its effects on adolescents and society are a major concern for practitioners, researchers, and policymakers alike [4].
Current attempts to support this population are largely designed to target specific conditions (e.g., depression [5]). However, 60% of adolescents with one diagnosable mental illness have one or more additional conditions [6]. Mental health comorbidity – the presence of two or more mental illnesses in an individual - is the rule rather than the exception and has been associated with greater clinical severity and a poorer overall quality of life [7]. As the prevalence of mental illness continues to rise, attention has turned toward addressing gaps in our understanding of ‘what works, for whom’ to mitigate risk factors for mental illness among adolescents and increased investment into effective early intervention and population-level mental health promotion [8] Scalable support, with a focus on prevention, has the potential to significantly improve outcomes for those most at risk of developing mental illness, reducing the severity and prevalence of disorders among adolescents [9]
A Transdiagnostic Approach to Adolescent Mental Health
Transdiagnostic interventions are designed to be directly effective across several mental illnesses, altering psychopathological processes common to multiple conditions (e.g. emotion regulation). They have the potential to offer broader, more effective support for adolescents struggling with their mental health[10]. Indeed, emerging evidence suggests the transdiagnostic approach is effective in targeting diverse psychopathologies in adolescents, and activates a range of related, beneficial developmental cascades, including improvement in social and academic outcomes, as well as improved sleep[11]. A transdiagnostic approach to treatment is also considered to be time- and cost-effective compared to disorder-specific strategies and may offer a more sustainable alternative to treatments currently available to this population[7]
Emotion Regulation – A Transdiagnostic Mechanism
Emotion regulation (ER) has received increased attention in recent years as a transdiagnostic mechanism and clinical target in psychological treatment [12]. Though the concept of ER remains unclear by definition, it can be broadly understood as a multidimensional process wherein an individual monitors, evaluates and shapes their emotions, when they have them, and how they internally experience or outwardly express them [12]. This process is typically thought to be goal-directed, helping individuals to meet the demands of their environment and achieve their ambitions (e.g. remaining calm to resolve a conflict) [13]. There have been several different conceptualisations of emotion regulation, but by far the most influential is the ‘Process model of Emotion Regulation’[14], which describes the sequence of an emotional experience as it unfolds, and the distinct processes employed by an individual to manage this. According to this model, an individual recognises an ER goal (e.g. to communicate to others; to modify behaviour), selects, and finally implements specific ER strategies[15]. Gross defined a set of five distinct ER processes occurring at different points in an emotional experience (see Fig. 1): situation selection, situation modification, attentional deployment, cognitive change, and response modulation [15]. Each of these strategies can be understood to influence an individual’s emotional response in a way that can be interpreted as adaptive (e.g., problem-solving, acceptance) or maladaptive (e.g., withdrawal, suppression [14]), depending on the context.
[Fig. 1 Process Model of Emotion Regulation – file too large (see separate document)]
Maladaptive patterns of emotional experience or expression are typically understood as emotion dysregulation and have physiological, cognitive, and social consequences[14, 15]. Emotion dysregulation can also be understood to represent problematic emotion dynamics: persistence, lability, and intensity of emotions[16]. Evidence demonstrates emotion dysregulation is present across a range of psychopathologies, including internalising (e.g., generalised anxiety disorder, major depressive disorder, dysthymia) and externalising disorders (e.g., attention-deficit/hyperactivity disorder [ADHD], conduct disorder, oppositional defiant disorder [17]). For example, generalised anxiety disorder has been associated with a lack of understanding of emotions and an increased reliance on ER strategies that could be understood as maladaptive, such as withdrawal[17]. Similarly, ADHD is characterised by individuals’ emotion regulation deficits and emotion reactivity [18] , whilst a core tenet of borderline personality disorder is the overreliance on strategies to regulate emotions, which can be thought of as maladaptive, but which provide relief (e.g. parasuicide, impulsive behaviour; [19]).
Though most evidence on the impact of emotion (dys-)regulation on psychopathology has been derived from adult populations [20], recent findings are beginning to show a close association between emotion (dys-)regulation and psychopathology in adolescence [21]. Evidence indicates a significant shift in ER between ages 13 and 15 (e.g., access to strategies, use of adaptive vs. maladaptive strategies), suggesting that adolescence is a particularly vulnerable period in the development of ER [22]. Therefore, interventions targeting ER as a transdiagnostic construct central to the development and maintenance of psychopathology may reduce the risk and severity of adolescent psychopathology.
Approaches to improving emotion regulation in adolescents
Existing psychological interventions adopt different approaches to improving emotional regulation. Some focus on reducing the use of ER strategies which may be understood as maladaptive, such as rumination (e.g., Rumination-focused cognitive behavioural therapy, RF-CBT [23]), while others focus on increasing the use of strategies which may be understood as adaptive, such as acceptance (e.g., Acceptance and Commitment Therapy, ACT [24]). Others move beyond modifying the use of specific strategies and instead focus on developing wider ER skills (e.g. identifying and labelling emotions, understanding the context in which emotions occur, applying distress tolerance techniques) (e.g., Dialectical Behaviour Therapy, DBT; [19]). The adult literature indicates that such interventions can improve ER and mediate decreases in psychopathological symptoms within certain diagnoses, such as anxiety [25]. However, the effectiveness of these interventions in improving multiple mental health and functional outcomes (e.g., academic achievement), rather than specific and individual symptom groups, is largely unknown [26]. As such, the potential utility of emotion dysregulation as a transdiagnostic treatment target for adolescents requires further investigation.
Much of the research to date has focused on the delivery of in person ER interventions, despite a growing number of digital solutions for adolescent ER and psychopathology [21]. Some attempts have been made to examine the effectiveness of digital interventions targeting ER in adolescents and emerging findings demonstrate that, in general, such interventions (e.g., digital games, virtual reality therapies) may be effective in improving ER [27]. Digital interventions have a greater capacity for innovation and engagement with adolescents[28] and the potential to extend effective care cost-effectively and sustainably[29], but more research is needed to determine how such interventions can be applied at scale to support this population.
Bridging the Gap: Self -directed Digital Technology for Adolescent Emotion Regulation
Current service provision for adolescents is almost universally described as overwhelmed, inadequately funded, and lacking the capacity to meet rising demand [9]. Specialised treatments that rely on specific roles for delivery (that cannot be easily scaled up) paradoxically risk compounding inequality of access to help, which is in and of itself accepted as a key social determinant of mental health among populations [9]. Improving adolescents’ access to evidence-based psychological therapies is a key focus of public health [8] prompting investment and research into more accessible, universal digital solutions for mental health.
An increasing number of innovative self-directed digital interventions (e.g., mobile apps) are being developed, which target emotion regulation and related processes (e.g. emotional self-awareness [28, 29]). Such interventions are led by the service user, with little to no support from anyone else (e.g., therapist, parent/carer), and aim to widen access to support for adolescents. Despite a growing number of self-directed digital interventions made available to adolescents, the effectiveness of interventions delivered in this self-directed and digital format for improving emotion regulation and psychopathology is, as yet, unclear. Further, more evidence is needed to determine the ‘active ingredients’ of self-directed digital interventions that most improve emotion regulation in adolescents [30]. As the prevalence of adolescent mental health problems increases, innovative digital solutions could help to ensure that a broad range of adolescents can access and engage in support for their mental health.
Review Objectives
Despite an increase in the number of available self-directed digital interventions for emotion regulation, evidence about their effectiveness among adolescent populations has yet to be synthesised. As such, this systematic review will investigate evidence on current self-directed digital interventions developed for adolescents (aged 11-18 years), and their effectiveness in addressing emotion (dys-)regulation, psychopathology, and functioning (e.g., academic achievement). This review provides an important extension to existing work which has thus far demonstrated the effectiveness of in-person or therapist-supported interventions available for young people (aged 6 – 24 years [17, 21]), as well as the utility of a broad spectrum of digital emotion regulation interventions for adolescents [27]. This review takes a more specific focus to develop evidence on a burgeoning number of self-directed, scalable, digital mental health interventions available to adolescents with or without diagnosed psychopathology. Specifically, we sought to answer the following research questions:
- Are current self-directed digital interventions that target ER effective in improving emotion (dys-)regulation in adolescents?
- What are the specific components (e.g. mood monitoring) of these interventions that most improve emotion (dys-)regulation in adolescents?
- Are these interventions effective treatments for psychopathology and for improving functional outcomes (e.g. academic achievement)?
- Are current self-directed digital interventions that target ER acceptable and feasible for use within an adolescent population?