Video gaming: observational, genetic, and causal associations with cognition and health
Background: We present an overview of phenotypical and genetic correlates of gaming behavior, illuminating the nature of the relationship between gaming and key health outcomes. Previous research has mostly focused on the potentially harmful effects of gaming. Given that lots of people play videogames, it is crucial to understand individual differences in gaming and causal mechanisms underlying links with negative, but also positive outcomes.
Methods: We investigate how gaming relates to demographics, health behavior, socioeconomic stratification, cognition, and, ultimately, health outcomes using a large population-based sample (UK Biobank, maximum N= 455,445). In addition, we identify genetic risk factors for gaming behavior using genome-wide association analyses (GWAS, N= 537,042). We leverage the GWAS results to explore (biological) overlap with other traits (genetic correlation) and to test putatively causal associations with health outcomes (Mendelian randomization, a form of instrumental variable analysis that relies on genetic variants as instruments).
Results: We found many positive associations between gaming behavior and physical health, exercise, smoking, and sedentary behavior. There was also a positive association with intelligence and income. We identified genetic variants that were associated with gaming behavior, with all combined explaining 7% of the variance. Genetic predisposition for gaming strongly overlapped with genetic predisposition for cognitive, socioeconomic, mental health, substance use, personality, neurological, and physical health traits. Mendelian randomization analyses provided support for a causal interpretation of some of these associations. We found evidence that gaming causally contributed to ADHD, autism, and BMI. Potentially beneficial causal effects of gaming included a positive effect on IQ and a negative effect on schizophrenia risk. In the other direction, we found evidence that ADHD, smoking, and a higher IQ increased gaming behavior.
Conclusions: We conclude that gaming is a complex trait that is associated both with positive and negative outcomes. Our research is in line with the cautiousness with which gaming has been portrayed in science and media, although our findings emphasize the importance of health behavior, rather than aggressiveness or loneliness as likely deleterious outcomes. Also, the potential of gaming to increase cognitive functioning and decrease schizophrenia risk form exciting avenues for more research. Hardly any interventions are available that have such effects, and it is paramount to investigate under what circumstances these crucial benefits might be reaped, while decreasing the potential harmful effects on other health outcomes.
