Connectome-based prediction of craving for gaming in internet gaming disorder.

BACKGROUND: Craving-related brain responses have been associated with the emergence and maintenance of addictions. However, little is known about brain network organizations underlying cravings in internet gaming disorder (IGD). METHODS: Sixty-six IGD subjects and 61 matched individuals with recreational game use (RGU) were scanned while performing a cue-craving task. A recently developed whole-brain analysis approach, connectome-based predictive modelling (CPM) with leave-one-out cross-validation was conducted to identify networks that predicted craving responses in IGD. Then, the craving network was tested in different brain states (cue-craving under deprivation) to investigate replicability. RESULTS: CPM identified an IGD craving network, as indicated by a significant correspondence between predicted and actual craving values (r = 0.49, p < 0.001), characterized by within-network default mode (DMN) connectivity and connectivity between canonical networks implicated in executive/cognitive control (frontoparietal, medial frontal, DMN) and reward responsiveness (subcortical, motor/sensory). Network strength in the cue-craving task during gaming deprivation also predicted IGD craving scores (r = 0.43, p = 0.017), indicating network replication across brain states. CONCLUSIONS: The CPM results demonstrate that individual differences in cognitive, attention, and control network function can predict craving intensities in IGD subjects. These networks may be targets for potential interventions using brain modulation.

Imbalanced sensitivities to primary and secondary rewards in internet gaming disorder.

BACKGROUND: Internet gaming disorder (IGD) is a type of behavioral addiction characterized by poorly controlled and interfering patterns of game playing. Studies have suggested that the IGD is usually accompanied by increased desire or craving for gaming, suggesting that secondary rewards related to gaming may become more salient than those for primary rewards like food. However, this hypothesis has not been formally tested and potential neural mechanisms remain unclear. METHODS: This is a functional magnetic resonance imaging (fMRI) study. Twenty-one IGD subjects and 23 matched individuals with recreational game use (RGU) were scanned when exposed to gaming (secondary rewards), food (primary rewards) and neutral cues. Group-by-cue-type interaction analyses and subsequent within-group analyses for fMRI data were performed and seed-based functional connectivity (FC) analyses explored further potential neural features. RESULTS: IGD subjects' subjective craving responses to gaming cues were higher than to food cues, while the opposite was observed in RGU subjects. Group-by-cue interaction effects implicated the precuneus and precuneus-caudate FC. Simple effect analysis showed that for IGD subjects, gaming-related cues elicited higher FC in precuneus-caudate relationships than did food-related cues. In the RGU subjects, the opposite was observed. Significant correlations were found between brain features and craving scores. CONCLUSIONS: These results support the hypothesis regarding imbalances in sensitivities to different types of reward in IGD, and suggest neural mechanisms by which craving for gaming may make secondary rewards more salient than primary ones, thus promoting participation in addictive patterns of gaming.

Altered modular segregation of brain networks during the cue-craving task contributes to the disrupted executive functions in internet gaming disorder.

BACKGROUND: Previous studies have shown that gaming-related cues could induce gaming cravings and bring about changes in brain activities in subjects with Internet gaming disorder (IGD). However, little is known about the brain network organizations in IGD subjects during a cue-craving task and the relationship between this network organization and IGD severity. METHODS: Sixty-one IGD subjects and 61 matched recreational game users (RGUs) were scanned while performing a cue-craving task. We calculated and compared the participation coefficient (PC) among brain network modules between IGD subjects and RGUs. Based on the results, further group comparison analyses were performed to explain the PC changes and to explore the relationship between PCs and IGD severity. RESULTS: While performing a cue-craving task, compared with RGUs, IGD subjects showed significantly decreased PCs in the default-mode network (DMN) and the frontal-parietal network (FPN). Specifically, the number of connections between nodes in the ventromedial prefrontal cortex, anterior cingulate cortex, posterior cingulate cortex and other nodes in the DMN of IGD subjects was much larger than that in RGUs. Correlation results showed that the number of DMN intra-modular connections was positively correlated with addiction severity and craving degree. CONCLUSIONS: These results provide neural evidence that can explain why cognitive control, emotion, attention and other functions are impaired in IGD subjects in the face of gaming cues, which leads to compulsive behavior toward games. These findings extend our understanding of the neural mechanism of IGD and have important implications for developing effective interventions to treat IGD subjects.