10th June 2020
Adolescence (the stage between 10 and 24 years) is a period of life characterised by heightened sensitivity to social stimuli and the increased need for peer interaction. The physical distancing measures mandated globally to contain the spread of COVID-19 are radically reducing adolescents' opportunities to engage in face-to-face social contact outside their household. In this interdisciplinary Viewpoint, we describe literature from a variety of domains that highlight how social deprivation in adolescence might have far-reaching consequences. Human studies have shown the importance of peer acceptance and peer influence in adolescence. Animal research has shown that social deprivation and isolation have unique effects on brain and behaviour in adolescence compared with other stages of life. However, the decrease in adolescent face-to-face contact might be less detrimental due to widespread access to digital forms of social interaction through technologies such as social media. The findings reviewed highlight how physical distancing might have a disproportionate effect on an age group for whom peer interaction is a vital aspect of development.
Social interactions are proposed to be a basic human need, analogous to other fundamental needs such as food consumption or sleep. Indeed, feeling insufficiently connected to others is associated with profound and lasting negative consequences on physical and mental health, even leading to increased mortality. Current efforts to contain the spread of COVID-19 have required sudden and commonly mandated physical distancing, removing many regular sources of social connection from people's lives. Such measures are likely to have a substantial effect, not only on the economy and society, but also on individuals' mental health and wellbeing through factors such as reduced contact with other people. It is possible that the effects of such deprivation of social contact will extend beyond the period of physical distancing and might affect the population for years to come.
The negative effects of physical distancing and social deprivation might be particularly profound for adolescents (aged 10–24 years). Adolescence represents a sensitive period for social interaction.In this Viewpoint, we discuss evidence that human adolescents are hypersensitive to social stimuli and to the negative effects of social exclusion.
We review animal models that show extreme forms of social deprivation, including complete social isolation during adolescence, which have damaging effects on brain and behavioural development. This global crisis has, however, struck at a time when many adolescents are well positioned to mitigate some of these social shortfalls using digital means of connection. This Viewpoint therefore synthesises interdisciplinary scientific findings relating to adolescent social processing, social isolation, and digital social behaviours. We also highlight how adolescents might be particularly affected by social deprivation, especially the reduction of peer contact, and how this must be taken into account when considering the long-term consequences of global COVID-19 prevention measures.
Adolescence is a sensitive period of social development
In parallel with the hormonal and biological changes associated with puberty, adolescence is a time of profound psychological and social transformation. During adolescence, the social world and the peer interactions it enables become increasingly important. Compared with children (aged <10 years), adolescents spend more time with peers than with their family and form more complex peer relationships. The importance of obtaining peer social approval increases and peer influence is heightened in adolescence. Indeed, adolescents are markedly more sensitive to peer acceptance, rejection, and approval than are children or adults. This reorientation towards peers facilitates young people's development into independent adults, enabling them to foster a more complete sense of social self-identity, at the same time as building stronger affiliations with their peer group. Simultaneously, cognitive abilities such as self-referential processing, executive control, and mentalising, improve across adolescence, enabling young people to better understand other people's minds and take others' perspectives. The development of high-level cognitive processes provides adolescents with the mental machinery to reflect on themselves and other people and to navigate social networks that start out as unstable and less reciprocal and gradually become more refined and reciprocal throughout adolescence.
Physical distancing measures to contain the spread of COVID-19 have removed many sources of face-to-face social connection from people's lives, which might affect people's mental health, particularly in adolescence, a period of life characterised by a heightened need for peer interaction
Animal research suggests there are unique effects of social isolation and social deprivation on brain and behaviour in adolescence; although the isolation in these studies is more extreme than the reduced social interaction associated with physical distancing, this literature suggests that adolescents might be particularly affected by deprivation of their social needs
Adolescents' use of digital technologies and social media might mitigate some of the negative effects of physical distancing
We call for an increased sensitivity during the COVID-19 response to the needs of adolescents, for whom peer interaction is a vital aspect of development
Indeed, adolescence can be considered a sensitive period for social development, which might be partly dependent on the development of the social brain: the network of brain areas involved in social perception and cognition that allows us to understand others. As with most regions within the human cortex, the structure of the social brain develops substantially throughout adolescence. Multiple longitudinal MRI studies have shown that, across the cortex, the volume of grey matter, mostly consisting of cell bodies and synapses, declines from late childhood to the mid twenties, whereas the volume of white matter, consisting of myelinated axons, gradually increases. These macrostructural changes are thought to correspond to neurodevelopmental mechanisms at the microstructural level, including the myelination and growth of axons and synaptic reorganisation, which are partly dependent on environmental input and represent mechanisms of developmental neuroplasticity. Thus, the heightened neuroplasticity that characterises early development is proposed to continue into adolescence. For healthy development, parental and caregiver input is a crucial component, especially during early development, whereas later in development the influence of peers becomes an additional important element of the social environment.
Adolescence is also a period of heightened vulnerability to mental health problems, with 75% of adults who have ever had a mental health condition reporting that they first experienced symptoms before the age of 24. There is evidence that problems with peer relationships, peer rejection, bullying, and loneliness are risk factors for the development of affective conditions such as depression in adolescence. Conversely, high quality peer relationships appear to protect against mental health problems and strengthen adolescent resilience. It follows then that widespread changes in the social environment, such as enforced physical distancing and reduced face-to-face social contact with peers, might have a substantial effect on brain and behavioural development during adolescence.
It is important to note, however, that physical distancing might not affect all adolescents in the same way. For example, adolescents who are living with high functioning families and who have positive relationships with parents or caregivers and siblings might be less affected by physical distancing than adolescents who do not have positive family relationships or who are living alone. Furthermore, as physical distancing rules vary by country, region, and across time, some face-to-face contact with non-household members might be permitted for certain adolescents. Nevertheless, many young people around the world currently have substantially fewer opportunities to interact face-to-face with peers in their social network, putting their social needs at risk of not being met at a crucial time of social development.
With physical distancing being enforced by governments around the world, society is at the start of a period of intense and widespread reduction of face-to-face social contact. This Viewpoint highlights the urgent need to consider the wellbeing and development of adolescents. Adolescents are at a unique period in their lives when the social environment is important for crucial functions in brain development, self-concept construction, and mental health. Rodent studies show substantial and potentially long-term effects of social deprivation and isolation in adolescence on neurochemistry, structural brain development, and behaviours associated with mental health problems. Research on social isolation has almost entirely been carried out in animal models and little is known about how social deprivation affects human development. This Viewpoint considers the potential of social media and other digital technologies to mitigate the severity of social deprivation effects on human adolescents, but more research focused on this precise question is needed.
There are many questions that remain unanswered. It is unknown how long the physical distancing measures will be in place and whether or how they will affect development and mental health in the longer term.
Even if physical distancing measures are temporary, several months of physical distancing represents a large proportion of a young person's life during a sensitive period of development, so it is possible that the effects will be more potent than for adults. Furthermore, there is little understanding on how the consequences of physical distancing compare with other stressors experienced by adolescents during the COVID-19 crisis, including economic pressures, uncertainty, and loss of public events marking key life stages and rites of passage. Adolescent physical distancing should therefore be given urgent consideration by policymakers and the opening of schools and other social environments should be a priority once physical distancing measures can be eased. There needs to be more information provided about the potential merits (and harms) of digital connection and governments need to address the digital divide by supporting access to digital connection in families irrespective of income or location. Finally, there is an urgent need to understand the short-term and long-term effects of social deprivation and physical distancing, reduced face-to-face social interaction, and increased use of digital means of connection, on human adolescent development and mental health.