Enhance Pavlovian-to-Instrumental Transfer In Internet Gaming Disorder

Objective:In recent years,Internet Gaming Disorder(IGD)had been included as a formal addictive mental disorder.And it is one of the main problems currently threatening the physical and mental health of people and the happiness of their families.Neutral cues(e.g.,yellow light)that were incentive salient after repeatedly Pavlovian exposure could influence one’s instrumental behavior(e.g.,response rate),a phenomenon called the Pavlovian-toinstrumental transfer effect(PIT).Enhanced PIT effects were found in several substance and behavioral addictions,such as alcohol dependence,tobacco use disorder,and gambling disorder.Addict-related cues not only increase the rate of addict-related behavior(specific PIT effect)but also may change other rewarding(such as monetary rewards)-driven behavior(general PIT effect).The PIT effects may help to better explain the clinical phenomena,such as the outof-control drinking of alcohol-dependent patients,and the excessive attention of gambling disorders to gambling clues.However,it is not clear whether IGD will show similar PIT effects as other addictive disorders.The study aimed to explore PIT effects in individuals with IGD.Study 1 examined whether IGD had abnormal specific PIT effects and the correlation between PIT effects and the severity of addiction.Study 2 investigated whether IGD had abnormal general PIT effect and its clinical relevance.Methods:Study 1 administrated a full transfer PIT task to IGD individuals(n=40)and health controls(n=50),and compared the amount of specific PIT effects between the two groups.The severity of the IGD symptoms was assessed by two self-reported questionnaires,the Chinese version 9-item dichotomous Internet Gaming Disorder Scale(IGDS),and the Internet Addiction Test(IAT).Study 2 administered a single-lever PIT task to IGD individuals(n=30)and health controls(n=31),and compared the general PIT effects between the two groups.The severity of the IGD symptoms was assessed by two self-reported questionnaires as study 1.Results:Study 1 found that:1)Compared with the healthy controls,the IGD showed enhanced game-specific PIT effects,and the Pavlovian clues related to the game led to increased game-related behavioral responses;2)In the IGD group,the specific PIT effects were positively correlated with IAT score(r=0.32,p=0.047).Study 2 found that:1)Compared with the healthy controls,the IGD showed enhanced general PIT effects,with the change of the background Pavlov condition cue value,the instrumental behavior of IGD changed stronger;2)Game pictures will reduce the correct rate of IGD(the correct behavior of getting monetary rewards).However,correlation analysis did not find significant correlations between the general PIT effects of the IGD group and the severity of IGD symptoms(including the DGT,craving level,start age of game-play,scores of IGDS,and scores of IAT).Conclusion:Similar to other addictions,IGD individuals showed enhanced specific and general PIT effects related to HC,indicating that IGD individuals were significantly more motivated to gaming clues than healthy controls.More importantly,this incentive salience can not only significantly affect the gamingrelated behavior of IGD individuals,but also significantly affect other rewarddriven behaviors.The specific PIT effects were related to the severity of addictive symptoms.But this study did not find correlations between the general PIT effects and clinical variables,indicating that the general PIT effects may have components other than incentive salience,which is worth further exploration.