Supplementary Material for: Altered Neural Activity in the Anterior and Posterior Insula in Individuals with Problematic Internet Use

2015-05-28T00:00:00Z (GMT) by Yoon H. Kim S.A. Ahn H.M. Kim S.H.
<b><i>Background:</i></b> Individuals with problematic Internet use (PIU) are known to experience increased craving for immediate monetary reward despite long-term negative consequences. What remains unclear is whether their sensitivity to monetary loss is altered. We investigated neural alterations in brain regions involved in the anticipation of a monetary reward and loss avoidance in order to advance our understanding of the characteristics of PIU. <b><i>Methods:</i></b> A total of 11 adults with PIU and 22 age-matched controls participated in this functional magnetic resonance imaging study. Inside the scanner, participants performed a monetary incentive learning task during which they chose one of two fractal stimuli associated with monetary gain (reward trials) or avoidance of monetary loss (avoidance trials). <b><i>Results:</i></b> We found that, relative to controls, activity in the posterior insula during reward anticipation was greater in participants with PIU, whereas its activity during avoidance anticipation was reduced. No group differences in activation were found during reception phases. <b><i>Conclusions:</i></b> Given the roles of the posterior insula in the cortical representation of somatosensory arousal, our results suggest that individuals with PIU may experience more elaborate somatosensory arousal during the anticipation of monetary reward and yet experience less elaborate somatosensory arousal during the anticipation of loss avoidance compared with typical controls.