Dimensional neuroimaging: (Internet) Gaming Disorder symptoms according to the WHO and APA frameworks associate with lower striatal volume

Growing concerns about the addictive nature of internet and computer games led to the endorsement of Internet Gaming Disorder (IGD) as an emerging disorder by the American Psychological Association (APA) in 2013 and the recognition of Gaming Disorder (GD) as a new diagnosis by the World Health Organization (WHO) in 2019. While the definition of clear diagnostic criteria for IGD is beneficial for clinicians and those in need of treatment, it may also stigmatize normal behavior. Furthermore, the neurobiological mechanisms underlying IGD symptoms, and whether they resemble those of other addictive disorders remains highly debated. To this end the present study employed a dimensional imaging approach to determine associations between IGD symptom-load according to the APA and WHO diagnostic frameworks and brain structure in a comparably large sample of healthy subjects. It was found that higher symptom-load on psychometric tests assessing the APA and WHO diagnostic frameworks convergently associated with lower volumes of the striatum. The present results suggest for the first time a neurobiological foundation of the proposed diagnostic criteria for IGD according to both diagnostic classification systems, further indicating that the transition from non-disordered to disordered gaming is accompanied by progressive neuroplastic changes in the striatum, thus resembling progressive changes in other addictive disorders.