| In recent years,Internet games have appeared in the mainstream market as a convenient and fast entertainment method.Long-term indulge in Internet games will bring many negative effects on personal life,study and work,even lead to the addiction of Internet games.Internet game disorder(IGD)refers to an individual’s repeated and uncontrolled addiction to Internet games that results in his or her mental or physical disorder.Previous studies have explored the characteristics of risk decision making and emotional response of IGD by using sequential risk decision task.In this task,the subjects earn as much gold coins as possible by choosing to open the box or stop opening the box.There may be gold coins or ghost in each box.If subjects choose to open the box and hit the ghost,they will lose all the coins(loss result).If subjects choose to stop opening the box,then collect the gold earned in this round(all the gold before getting the ghost will be deemed as the optimal result,and the rest will be deemed as non-optimal result).The study found that IGD took more risks than healthy people.In the face of non-optimal results,IGD are even less relieved.In addition,the change of risk situation will not only directly affect individual’s risk decision-making,but also affect individual’s regret emotion.However,few research has been conducted to investigate the difference in risk decision making emotional response between IGD and healthy people in different risk situations.This study will use sequential risk taking task in different risk situations,combined with functional magnetic resonance imaging(fMRI),in the sequential risk decision-making task,we manipulated the high and low risk situations by changing the value of gold coins in the box,and investigated the characteristics of emotional response to risk decision-making and related brain activities of IGD in different risk situations.In addition,the resting-state fMRI was also used to investigate whether there were abnormalities in brain functional connectivity(rs FC)in the IGD.The results of this study are as follows:(1)Behavioral results showed that,IGD group showed significantly higher levels of craving for Internet game compared to healthy control(HC)group;In the aspect of risk decision-making,IGD group was more risky;In terms of emotional response,when faced with a non-optimal outcome,IGD group was less relieved than HC group,and was less willing to miss the opportunities.(2)The results of the task-fMRI showed that when faced the non-optimal outcomes,the dorsolateral prefrontal cortex activation was lower in IGD group compared to HC group.In the gain situation,by using parametric analysis,we found that the activation of striatum,orbitofrontal cortex and anterior cingulate gyrus increased as the outcome got better.In addition,as the emotional score was higher and higher,the individual’s striatum was more activated.In the loss situation,the activation of anterior cingulate gyrus in the low-risk condition was stronger than that in the high-risk condition.Besides,the activation of anterior cingulate gyrus was significantly positively correlated with the emotional scores in the low-risk condition,while this correlation wasn’t found in the high-risk situation.(3)Resting-state fMRI study found that,compared with HC group,IGD group showed significantly increased rs FC between the superior frontal gyrus and thalamus.In HC group,the rs FC between the superior frontal gyrus and thalamus was positively correlated with the scores of Internet game craving scale.In summary,combined with behavioral results,task state fMRI and resting state fMRI,this study explored the characteristics of emotional response to risk-making and related brain activities of IGD under different risk situations.We found that IGD was more likely to take risks and less likely to miss opportunities.When faced the non-optimal outcomes,the dorsolateral prefrontal cortex of IGD was abnormally activated,this may be due to the impaired inhibitory control ability.In addition,the rs FC between the superior frontal gyrus and thalamus was abnormally enhanced,and related to the degree of Internet game craving,of IGD,these results reflected the abnormalities of the reward processing system related to superior frontal gyrus and thalamus in the brain of IGD.The results of this study are helpful to further understand the decision-making behavior and brain activity characteristics of the IGD in the sequential risk decision-making task under different risk situations,so as to provide some new ideas for the intervention and withdrawal of IGD. |
