A new study shows that there might be a link between how much time children spend in front of screens (like phones, computers and television) and problems with their attention and their feelings. However, it’s possible that the genes children inherit from their parents could be influencing this link.
The study, carried out as part of the Adolescent Brain Cognitive Development (ABCD) Project, focused on children aged 9 to 11, of genetically assigned European ancestry, across 21 sites in the United States.
Screen Time and Mental Health: A Complicated Link
Previous studies indicated that excessive screen time may be associated with attention and internalising problems in children. However, this new study reveals that the connection is more intricate than previously thought. Even after accounting for factors such as age, sex, and sociodemographic variables, the study confirmed that more screen time is linked to an increase in attention and internalising problems in children. “Internalising” refers to the act or process of directing emotions, thoughts, or psychological symptoms inward, rather than expressing them outwardly through behaviour. It typically involves internal emotional struggles and distress.
Genetic Factors at Play
One of the most significant findings of this study is the role of genetic factors in this connection. To examine the impact of genetics, the researchers used polygenic risk scores (PRSs) for specific traits such as television time, attention-deficit/hyperactivity disorder (ADHD), and depression. A “polygenic risk score” is one way by which people can learn about their risk of developing a disease.
They discovered that these PRSs were not only associated with screen time but also with mental health problems in children.
‘Genetic Confounding’
The study discovered that genetics may be influencing both screen time and mental health. This factor can create a distorted perception of the relationship between the two. In essence, genetics could be a hidden variable affecting both screen time and children’s mental health, complicating the interpretation of their association. Genetic confounding is a phenomenon in epidemiology and genetics that occurs when the relationship between an exposure (such as a risk factor) and an outcome (such as a disease) is influenced or obscured by the presence of genetic factors.
The research assessed the extent of genetic confounding using various heritability estimates. Results showed that genetic confounding accounted for a significant portion of the link between screen time and attention problems. It also partially explained the association between screen time and internalising problems. In some scenarios, genetic confounding completely explained these associations.
The presence of genetic confounding in this relationship may affect the effectiveness of interventions designed to reduce screen time. Genetics play a pivotal role in the association between screen time and children’s mental health. By integrating genetic information and recognizing genetic confounding, researchers can achieve a more precise understanding of this complex relationship, ultimately benefiting youth mental health studies and interventions.
