Internet addiction (IA) is a major health problem and is associated with comorbidities like insomnia and depression. These consequences frequently confound neuroanatomical correlates of IA in those suffering from it. We enrolled a number of 123 healthy native German-speaking adults (53 male, mean age: 36.8 ± 18.86) from the Leipzig Study for Mind-Body-Emotion Interactions (LEMON) database, for whom diffusion MRI data, internet addiction test, brief self-control scale (SCS), coping orientations to problems experienced (COPE), and depression scores were available. DMRI connectometry was used to investigate white matter microstructural correlates of the severity of internet addiction identified through IAT, in a group of healty young individuals. A multiple regression model was adopted with age, gender, SCS total score, COPE total score, and BDI-sum as covariates to track white matter fibers in which connectivity was associated with IAT. The connectometry analysis identified a direct correlation between connectivity in the splenium of corpus callosum (CC), parts of bilateral corticospinal tracts (CST), and bilateral arcuate fasciculi (AF) (FDR = 0.0023001), and an inverse correlation of the connectivity in the genu of CC and right fornix (FDR = 0.047138), with the IAT score in healthy adults. We suggest connectivity in the CC and CST as well as fornix and AF to be considered as microstructural biomarkers of predisposition to IA in healthy population.
