Authors:Guang-Heng Dong, Min Wang, Jialin Zhang, Xiaoxia Du, and Marc N. Potenza
Background and aims
Although studies have suggested that individuals with Internet gaming disorder (IGD) may have impairments in cognitive functioning, the nature of the relationship is unclear given that the information is typically derived from cross-sectional studies.
Individuals with active IGD (n = 154) and those individuals no longer meeting criteria (n = 29) after 1 year were examined longitudinally using functional magnetic resonance imaging during performance of cue-craving tasks. Subjective responses and neural correlates were contrasted at study onset and at 1 year.
Subjects’ craving responses to gaming cues decreased significantly at 1 year relative to study onset. Decreased brain responses in the anterior cingulate cortex (ACC) and lentiform nucleus were observed at 1 year relative to onset. Significant positive correlations were observed between changes in brain activities in the lentiform nucleus and changes in self-reported cravings. Dynamic causal modeling analysis showed increased ACC–lentiform connectivity at 1 year relative to study onset.
After recovery from IGD, individuals appear less sensitive to gaming cues. This recovery may involve increased ACC-related control over lentiform-related motivations in the control over cravings. The extent to which cortical control over subcortical motivations may be targeted in treatments for IGD should be examined further.
Authors:Guangheng Dong, Hui Zheng, Xiaoyue Liu, Yifan Wang, Xiaoxia Du, and Marc N. Potenza
Online gaming has become a popular leisure activity, in which males more frequently develop Internet gaming disorder (IGD) compared to females. However, gender-related neurocognitive differences have largely not been systematically investigated in IGD.
Cue-elicited-craving tasks were performed before game playing and immediately after deprivation operationalized as a forced break from gaming when the Internet was disconnected. Ninety-nine subjects with IGD (27 males and 22 females) or recreational game use (RGU; 27 males and 23 females) provided functional MRI and subjective data. Analyses investigating effects of group (IGD and RGU) × gender (male and female) at different times (pre-gaming, post-gaming, and post–pre) on cue-elicited craving and brain responses were performed. Correlations between brain responses and subjective measures were calculated.
In pre-, post-, and post–pre tests, significant gender-by-group interactions (p < .001, cluster size > 15 voxels) were observed in the left dorsolateral prefrontal cortex (DLPFC). Further analyses of the DLPFC cluster showed that in post–pre comparisons, results were related to less engagement of the DLPFC in IGD, especially in females. In addition, at post-test, significant interactions were observed in the caudate, as females with IGD showed greater activation as compared to those with RGU.
The results raise the possibility that women with RGU may show better executive control than men when facing gaming cues, which may provide resiliency against developing IGD; however, once they develop IGD, their gaming may impair their executive control and enhance their cravings for gaming, which may make it more difficult to quit gaming.
Authors:Min Wang, Haohao Dong, Hui Zheng, Xiaoxia Du, and Guang-Heng Dong
Background and aims
Individuals with addictive disorders are usually characterized by impaired executive control, persistent craving and excessive reward-seeking. However, it is unclear whether there is a deviation in the connection pattern among the neural systems implicated in these problem behaviors.
One hundred thirty-six online gaming players were recruited in the current study (68 Internet gaming disorder (IGD) subjects and 68 recreational game users (RGUs) who served as controls matched on age, sex, years of education, and years of gaming). Dynamic interactions among the reward system (striatum), control system (prefrontal cortex), and the interoceptive awareness system (insula) were calculated and compared when subjects were facing gaming cues.
The results revealed that RGUs showed a significant positive correlation in the putamen-middle frontal gyrus (MFG)-insula neural pathway when facing gaming cues, which was missing in the IGD subjects. Additionally, dynamic causal modeling (DCM) analysis revealed that the MFG region was more inhibited by the putamen in the IGD subjects relative to the RGUs.
These findings suggest that the inhibitory neuromodulation of the putamen to the prefrontal cortex in IGD individuals undermines the balance among the tripartite systems. Our findings provide novel neurobiological evidence for understanding the internal connection bias of the addicted individual’s neural system and how the addictive disorder impairs executive control; consequently, the pathway from the striatum to the prefrontal cortex may serve as a potential biomarker to predict the risk of developing an addiction.
Authors:Ziliang Wang, Haohao Dong, Xiaoxia Du, Jin-Tao Zhang, and Guang-Heng Dong
Understanding the neural mechanisms underlying Internet gaming disorder (IGD) is essential for the condition's diagnosis and treatment. Nevertheless, the pathological mechanisms of IGD remain elusive at present. Hence, we employed multi-voxel pattern analysis (MVPA) and spectral dynamic causal modeling (spDCM) to explore this issue.
Resting-state fMRI data were collected from 103 IGD subjects (male = 57) and 99 well-matched recreational game users (RGUs, male = 51). Regional homogeneity was calculated as the feature for MVPA based on the support vector machine (SVM) with leave-one- out cross-validation. Mean time series data extracted from the brain regions in accordance with the MVPA results were used for further spDCM analysis.
Results display a high accuracy of 82.67% (sensitivity of 83.50% and specificity of 81.82%) in the classification of the two groups. The most discriminative brain regions that contributed to the classification were the bilateral parahippocampal gyrus (PG), right anterior cingulate cortex (ACC), and middle frontal gyrus (MFG). Significant correlations were found between addiction severity (IAT and DSM scores) and the ReHo values of the brain regions that contributed to the classification. Moreover, the results of spDCM showed that compared with RGU, IGD showed decreased effective connectivity from the left PG to the right MFG and from the right PG to the ACC and decreased self-connection in the right PG.
These results show that the weakening of the PG and its connection with the prefrontal cortex, including the ACC and MFG, may be an underlying mechanism of IGD.