Dysfunctional Prefrontal Function Is Associated with Impulsivity in People with Internet Gaming Disorder during a Delay Discounting Task.

Guangheng Dong,Xiaoxia Du,Jiaojing Xu,Hongli Zhou,Yifan Wang,Xiao Lin,Yanbo Hu

doi:10.3389/fpsyt.2017.00287

Abstract

Internet gaming disorder (IGD), defined as the persistent use of online games with ignorance of adverse consequences, has increasingly raised widespread public concerns. This study aimed at elucidating the precise mechanisms underlying IGD by comparing intertemporal decision-making process between 18 IGD participants and 21 matched healthy controls (HCs). Both behavioral and fMRI data were recorded from a delay discounting task. At the behavioral level, the IGD showed a higher discount rate k than HC; and in IGD group, both the reaction time (delay − immediate) and the discount rate k were significantly positively correlated with the severity of IGD. At the neural level, the IGD exhibited reduced brain activations in the dorsolateral prefrontal cortex and bilateral inferior frontal gyrus compared to HC during performing delay trials relative to immediate ones. Taken together, the results suggested that IGD showed deficits in making decisions and tended to pursuit immediate satisfaction. The underlying mechanism arises from the deficient ability in evaluating between delayed reward and immediate satisfaction, and the impaired ability in impulse inhibition, which may be associated with the dysfunction of the prefrontal activation. These might be the reason why IGD continue playing online games in spite of facing severe negative consequences.

Highlights

Internet gaming disorder (IGD) has increasingly raised widespread public concerns
Group comparison suggested that the IGD showed smaller blood oxygen level dependence (BOLD) signal differences, between delayed and immediate choice, over the left dorsolateral prefrontal cortex (DLPFC) and bilateral inferior frontal gyrus (IFG) than healthy controls (HCs) (Figure 4 and Table 2), which was consistent with our hypothesis
The IGD did not show any greater BOLD signals in the whole brain compared to HC

Summary

Introduction

Internet gaming disorder (IGD) has increasingly raised widespread public concerns. Studies using DDT have found that delayed rewards tend to be more steeply discounted in substance addicts in relation to alcohol [12], heroin [13], cocaine [14], methamphetamine [15], and pathological gamblers [16] when compared to healthy controls (HCs). There is evidence that individuals with IGD are more impulsive than recreational Internet gaming users and HC [17,18,19,20] These findings raise the possibility that the IGD, in accordance with drug and gambling addicts, show myopia for the future, i.e., preference for short-term rewards (e.g., Internet games) and ignorance for long-term losses (e.g., social relationship)

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Conclusion