Altered neural processing of negative stimuli in people with internet gaming disorder: fMRI evidence from the comparison with recreational game users

Neurophysiological characteristics of reward processing in individuals at different levels of gaming

Altered reward processing has been repeatedly reported in Internet gaming disorder (IGD). However, it remains unclear whether these changes are linked to the severity of addictive symptoms or the extent of gaming experience. This study examined the neurophysiological responses regarding reward anticipation and consummation in individuals at different levels of gaming (including 22 casual gamers, 31 regular gamers, and 27 individuals with IGD) through a monetary incentive delay task. Three event-related potential components during reward anticipation-cue-related P300 (Cue-P3), contingent negative variation, and stimulus-preceding negativity (SPN)-and two during reward consummation-feedback-related negativity and feedback-related P300 (FB-P3)-were measured. We found that IGD individuals exhibited greater Cue-P3 but lower SPN amplitude compared to casual gamers, while regular gamers fell between the two without significant differences. Regressions indicated that more extensive gaming experience, rather than the severity of the symptoms, primarily contributed to the increased Cue-P3 in IGD. No group differences were found during reward consummation. Our results highlight disrupted reward anticipation processing in IGD, characterized by increased attention bias toward reward cues (Cue-P3) but diminished cognitive resources for reward anticipation (SPN) and emphasize the role of gaming experience in increased attention bias in IGD.

Meta-analysis of structural and functional abnormalities in behavioral addictions

BACKGROUND

The incidence of behavioral addictions (BAs) associated with scientific and technological advances has been increasing steadily. Unfortunately, a large number of studies on the structural and functional abnormalities have shown poor reproducibility, and it remains unclear whether different addictive behaviors share common underlying abnormalities. Therefore, our objective was to conduct a quantitative meta-analysis of different behavioral addictions to provide evidence-based evidence of common structural and functional changes.

METHODS

We conducted systematic searches in PubMed, Web of Science and Scopus from January 2010 to December 2023, supplementing reference lists of high-quality relevant meta-analyses and reviews, to identify eligible voxel-based morphometry (VBM) and functional magnetic resonance imaging (fMRI) studies. Using anisotropic seed-based D-Mapping (AES-SDM) meta-analysis methods, we compared brain abnormalities between BAs and healthy controls (HCs).

RESULTS

There were 11 GMV studies (287 BAs and 292 HCs) and 26 fMRI studies (577 BAs and 545 HCs) that met inclusion criteria. Compared with HCs, BAs demonstrated significant reductions in gray matter volume (GMV) in (1) right anterior cingulate gyri extending into the adjacent superior frontal gyrus, as well as in the left inferior frontal gyrus and right striatum. (2) the bilateral precuneus, right supramarginal gyrus, and right fusiform gyrus were hyperfunction; (3) the left medial cingulate gyrus extended to the superior frontal gyrus, the left inferior frontal gyrus, and right middle temporal gyrus had hypofunction.

CONCLUSIONS

Our study identified structural and functional impairments in brain regions involved in executive control, cognitive function, visual memory, and reward-driven behavior in BAs. Notably, fronto-cingulate regions may serve as common biomarkers of BAs.

An Empirical Investigation of the Relationships Among Self-Esteem, Depression and Self-Serving Bias in People with Internet Gaming Disorder

Introduction

People are generally characterized by a self-serving bias which describes the tendency to ascribe positive outcomes or success to internal or personal causes (self-enhancement motivation) and ascribe negative outcomes or failure to external or situational causes (self-protection motivation). It has been found that the individuals with internet gaming disorder (IGD) who have low self-esteem and high depression exhibit an attenuated self-serving bias. However, the relationships among self-esteem, depression and self-serving bias are not clearly identified.

Methods

A sample of 138 IGD participants completed self-esteem and depression scales and a causal attribution task (Study 1) to examine the relationships among self-esteem, depression and self-serving bias (both self-enhancement and self-protection). In follow-up Study 2, 28 IGD participants were recruited to undertake self-affirmation intervention which can affirm one's sense of global self-view and bolster self-esteem to explore whether self-affirmation would trigger a reduction of depression and a raise of self-serving bias.

Results

The results of path analysis in Study 1 showed that the self-serving bias was predicted by self-esteem and depression, and the depression played a mediating role between self-esteem and self-serving bias. The results of Study 2 showed that the IGD participants reported higher self-esteem, lower depression and engaged in more self-protection motivation after affirming-self manipulation as compared with affirming-other manipulation.

Conclusion

These findings suggest that self-esteem predicts self-serving bias through depression and self-affirmation could trigger an increase of self-esteem, further decrease depression and improve self-serving bias for the individuals with IGD. The present article clearly identified the relationships among these factors and provided a new approach to promote positive self-concept in individuals with IGD. Future research is warranted to explore the lasting benefits of self-affirmation on domains of education, relationships and gaming withdrawal for the individuals with IGD among different populations.

Functional connectivity alterations in individuals with gaming disorder assessed by functional magnetic resonance imaging: a systematic review

Neuroimaging has continually advanced, playing a crucial role in the accurate diagnosis of various brain pathologies and disorders. This integrative review aimed to identify the main changes in brain connections found in fMRI scans of individuals with Internet Gaming Disorder (IGD). The data collection method involved searching for the terms "Magnetic Resonance Imaging", "Psychological Dependence" and "Internet Addiction Disorder" in the PubMed and Embase databases. Studies published between 2020 and January 2023 were included and manually analyzed through the virtual environment created in the "Rayyan" software, compiling a total of 18 scientific studies. The main findings reveal changes such as significant increases or decreases in functional connectivity in certain regions of the brain. Some potential negative impacts on the uncontrolled use of technologies among the young population were evaluated, such as the loss of inhibitory control in decision-making, transforming leisure into dependence, and although the IGD understands the associated risks and harms, it faces difficulties in resisting the desire to stop playing. This situation emphasizes the need for more long-term studies that can be comparative between different age groups. Conclusion, the brain regions with the most significant changes in functional connectivity in individuals with IGD symptoms are the prefrontal cortex, fronto-parietal regions, frontal gyrus, insula lobe, cingulate cortex and striatum. The lack of comprehensive knowledge about the effects of video game addiction across different age groups is a significant concern. Therefore, it is essential to carry out research that evaluates the impact of these technologies on different stages of human development.

The severity of addiction mediates loneliness and cortical volume in internet gaming disorder

Internet gaming disorder (IGD) subjects reported higher loneliness scores than healthy controls. However, the neural correlates underlying the association between loneliness and IGD remain unclear. Thus, the aim of this study was to explore the relationship between loneliness, online gaming addiction and brain structure. In the current study, structural MRI data were acquired from 84 IGD subjects and 103 matched recreational game users (RGUs). We assessed and compared their addiction severity, loneliness scores, and cortical volumes and analyzed the correlations among these values. Significant correlations were found between loneliness scores and brain volumes in the postcentral cortex, the medial orbitofrontal cortex, the rostral anterior cingulate cortex, and the temporal cortex. In addition, the addiction severity scores partly mediated the relationship between loneliness score and cortical volume in IGD. The results showed that participants with extreme loneliness had significant correlations with brain regions responsible for executive control, social threat surveillance and avoidance. More importantly, the severity of addiction mediates loneliness and cortical volume. The findings shed new insight into the neural mechanisms of loneliness and IGD and have implications for potential treatment.

Emotion dysregulation and Internet gaming disorder in young people: Mediating effects of negative affect and metacognitions

BACKGROUND

Recent studies have found that emotion dysregulation, negative affect, and metacognitions about online gaming are risk factors for Internet gaming disorder (IGD). However, few studies investigated the mechanisms underlying these interactions. The present study aimed to explore the relationships between emotion dysregulation and IGD, and the mediating effects of negative affect and metacognitions about online gaming.

METHODS

An online survey was conducted with young people (aged 10-24 years) who played video games. 1768 participants were included in this study. Observed variables, including emotion dysregulation, IGD, depression, anxiety, and metacognitions, were measured with self-report scales. Structural equation modeling (SEM) was used to analyze the relationships among the variables.

RESULTS

The results showed that emotion dysregulation positively predicted IGD through a fully mediated model which included the independent mediating effects of negative affect and metacognitions about online gaming and their sequential mediating effect. The model explained 76.1 % of the variance in IGD.

LIMITATIONS

This was a cross-sectional study which could not infer causality.

CONCLUSIONS

This study emphasizes that negative affect and metacognitions about online gaming mediate the effect of emotion dysregulation on IGD; moreover, metacognition may be a proximal factor of IGD. Thus, improving emotional regulation and modifying maladaptive metacognitions in young people may improve the prevention and treatment of IGD.

Neuroimaging the effects of smartphone (over-)use on brain function and structure-a review on the current state of MRI-based findings and a roadmap for future research

The smartphone represents a transformative device that dramatically changed our daily lives, including how we communicate, work, entertain ourselves, and navigate through unknown territory. Given its ubiquitous availability and impact on nearly every aspect of our lives, debates on the potential impact of smartphone (over-)use on the brain and whether smartphone use can be "addictive" have increased over the last years. Several studies have used magnetic resonance imaging to characterize associations between individual differences in excessive smartphone use and variations in brain structure or function. Therefore, it is an opportune time to summarize and critically reflect on the available studies. Following this overview, we present a roadmap for future research to improve our understanding of how excessive smartphone use can affect the brain, mental health, and cognitive and affective functions.

The unbalanced behavioral activation and inhibition system sensitivity in internet gaming disorder: Evidence from resting-state Granger causal connectivity analysis

BACKGROUND

Patients with behavioral or substance addiction show an unbalanced behavioral activation system (BAS) and behavioral inhibition system (BIS) sensitivity. However, the relationship between internet gaming disorder (IGD) and BAS/BIS is obscure and the neurobiological mechanism underlying this relationship remains unclear.

METHODS

We recruited 154 IGDs and 229 recreational game users (RGUs) in the current study. First, we explored the relationship between BAS/BIS and IGD. Second, subjects were subdivided into subgroups by BAS/BIS sensitivity. Third, whole-brain Granger causal connectivity (GCC) of striatum and amygdala subdivisions was estimated for the subgroup. Fourth, mediation analysis was performed to explore the role of connectivity in the relationship between IGD and BAS/BIS sensitivity.

RESULTS

We found the IGD group scored higher than the RGU on BIS and BASf (fun-seeking) sensitivity. Then, we identified 4 (2*2) subgroups: low/high risk of IGD with low/high BAS/BIS sensitivity groups. Two-way ANCOVA main results of interaction effects showed that in the high BAS/BIS group, the RGU exhibited increased strength in the GCC from the left putamen to the right cuneus, and the IGD exhibited decreased strength in the GCC from the right medial frontal gyrus to the caudate, from the left superior frontal gyrus to the centromedial amygdala, and from the right superior parietal lobule to the left laterobasal amygdala. Moreover, the GCC from the centromedial amygdala to the middle frontal gyrus mediated the directional relationship between BIS and IAT (Young's internet addiction test) scores.

CONCLUSIONS

The IGD individuals exhibited higher BIS and BAS-fun seeking sensitivity. Moreover, IGD with unbalanced BAS/BIS sensitivity exhibited alternative connectivity patterns involving amygdala and striatum subdivisions. These findings suggest a neurobiological mechanism for an alternation between IGD and RGU with different BAS/BIS sensitivity.

Neural activations to loss anticipation mediates the association between difficulties in emotion regulation and screen media activities among early adolescent youth: A moderating role for depression

BACKGROUND

Screen media activities (SMAs; e.g., watching videos, playing videogames) have become increasingly prevalent among youth as ways to alleviate or escape from negative emotional states. However, neural mechanisms underlying these processes in youth are incompletely understood.

METHOD

Seventy-nine youth aged 11-15 years completed a monetary incentive delay task during fMRI scanning. Neural correlates of reward/loss processing and their associations with SMAs were explored. Next, brain activations during reward/loss processing in regions implicated in the processing of emotions were examined as potential mediating factors between difficulties in emotion regulation (DER) and engagement in SMAs. Finally, a moderated mediation model tested the effects of depressive symptoms in such relationships.

RESULT

The emotional components associated with SMAs in reward/loss processing included activations in the left anterior insula (AI) and right dorsolateral prefrontal cortex (DLPFC) during anticipation of working to avoid losses. Activations in both the AI and DLPFC mediated the relationship between DER and SMAs. Moreover, depressive symptoms moderated the relationship between AI activation in response to loss anticipation and SMAs.

CONCLUSION

The current findings suggest that DER link to SMAs through loss-related brain activations implicated in the processing of emotions and motivational avoidance, particularly in youth with greater levels of depressive symptoms. The findings suggest the importance of enhancing emotion-regulation tendencies/abilities in youth and, in particular, their regulatory responses to negative emotional situations in order to guide moderate engagement in SMAs.

Enhanced resting-state EEG source functional connectivity within the default mode and reward-salience networks in internet gaming disorder

BACKGROUND

The two key mechanisms affected by internet gaming disorder (IGD) are cognitive and reward processing. Despite their significance, little is known about neurophysiological features as determined using resting-state electroencephalography (EEG) source functional connectivity (FC).

METHODS

We compared resting-state EEG source FC within the default mode network (DMN) and reward/salience network (RSN) between patients with IGD and healthy controls (HCs) to identify neurophysiological markers associated with cognitive and reward processing. A total of 158 young male adults (79 patients with IGD and 79 HCs) were included, and the source FC of the DMN and RSN in five spectral bands (delta, theta, alpha, beta, and gamma) were assessed.

RESULTS

Patients with IGD showed increased theta, alpha, and beta connectivity within the DMN between the orbitofrontal cortex and parietal regions compared with HCs. In terms of RSN, patients with IGD exhibited elevated alpha and beta connectivity between the anterior cingulate gyrus and temporal regions compared with HCs. Furthermore, patients with IGD showed negative correlations between the severity of IGD symptoms and/or weekly gaming time and theta and alpha connectivity within the DMN and theta, alpha, and beta connectivity within the RSN. However, the duration of IGD was not associated with EEG source FC.

CONCLUSIONS

Hyper-connectivities within the DMN and RSN may be considered potential state markers associated with symptom severity and gaming time in IGD.

Cortical surface variation in individuals with excessive smartphone use

Excessive smartphone use has been repeatedly related to adverse effects on mental health and psychological well-being in young adults. The continued investigation of the neurobiological mechanism underlying excessive smartphone use - sometimes also referred to as "smartphone addiction" (SPA) - is considered a top priority in system neuroscience research. Despite progress in the past years, cortical morphology associated with SPA is still poorly understood. Here, we used structural magnetic resonance imaging (MRI) at 3 T to investigate two cortical surface markers of distinct neurodevelopmental origin such as the complexity of cortical folding (CCF) and cortical thickness (CTh) in individuals with excessive smartphone use (n = 19) compared to individuals not fulfilling SPA criteria (n-SPA; n = 22). SPA was assessed using the Smartphone Addiction Inventory (SPAI). CCF and CTh were investigated using the Computational Anatomy Toolbox (CAT12). SPA individuals showed lower CCF in the right superior frontal gyrus as well as in the right caudal (cACC) and rostral anterior cingulate cortex (rACC) compared to n-SPA individuals (TFCE, uncorrected at p < 0.001). Following a dimensional approach, across the entire sample CCF of the right cACC was significantly associated with SPAI total score, as well as with distinct SPAI subdimensions, particularly time spent with the device, compulsivity, and sleep interference in all participants (n = 41; p < 0.05, FDR-corrected). Collectively, these findings suggest that SPA is associated with aberrant structural maturation of regions important for cognitive control and emotional regulation. This article is protected by copyright. All rights reserved.

Altered neural responses to missed chance contribute to the risk-taking behaviour in individuals with Internet gaming disorder

Missed chance is a powerful factor in shaping risk-taking behaviour. The abnormal risk-taking behaviour is an obvious feature of individuals with Internet gaming disorder (IGD). However, the relationship between the neural responses to missed chance and risk-taking behaviour in IGD individuals remains unclear. In the current fMRI study, 28 IGD subjects (12 female, 23.04 ± 2.43 years old) and 26 healthy control (HC) subjects (13 female, 23.58 ± 2.67 years old) participated in fMRI scanning during performance of a sequential risk-taking task. The general linear model and the psycho-physiological interaction analyses were conducted to explore the difference in neural responses between the two groups. The results showed that IGD subjects reported more regret for the large missed chance and took more risk than HC subjects. Moreover, compared with HC subjects, IGD subjects exhibited greater activations in brain regions like ventral striatum (VS) and superior frontal gyrus (SFG), and stronger VS-thalamus functional connectivity for the large missed chance. Additionally, among IGD subjects, the SFG activation for the large missed chance was positively correlated with the risk-taking behaviour. Together, the results revealed the altered neural responses to missed chance contributed to the risk-taking behaviour in IGD individuals. The findings could help to clearly understand why IGD individuals continue playing online games despite the risks of widely known and could provide a new perspective for the intervention of IGD.

Extended classifier system with continuous real-coded variables for feature extraction of instantaneous pulse-rate variability and respiration of individuals with gaming disorder

Background

Individuals with gaming disorder (GD) exhibit autonomic nervous system responses that indicate dysfunctional emotion regulation. Pulse rate variability (PRV) is a valuable biomarker for investigating the autonomic function of patients with mental disorders. Because individuals with GD dynamically regulate emotions during gaming, the PRV response relating to GD is not well understood. To investigate the dynamic PRV responses of individuals with GD, this study proposed the indexes of instantaneous PRV (iPRV) and instantaneous respiratory frequency (IF_resp) of arterial blood pressure signals using empirical mode decomposition and normalized direct-quadrature algorithms. iPRV consists of low-frequency (LF), high-frequency (HF), and very high-frequency (VHF) bands. Moreover, a novel method of extended classifier system with continuous real-coded variables (XCSR) was used to detect GD and extract GD-related iPRV features using iPRV and IF_resp as input data.

Results

A total of 32 college students without depressive and anxiety symptoms or cardiovascular diseases were recruited in this study. Participants were grouped into the high-risk GD and low-risk GD using both Chen Internet Addiction Scale and Internet Gaming Disorder Questionnaire. Their arterial blood pressures signals were measured while they watched gameplay videos with negative or positive emotional stimuli. Seven participants with high-risk GD exhibited significantly increased normalized VHF (nVHF) PRV and IF_resp readings and significantly decreased normalized LF (nLF) PRV readings and LF/HF PRV ratios (from baseline) during negative or positive gameplay videos stimuli. These participants also exhibited higher nVHF PRV and lower nLF PRV readings and LF/HF PRV ratios when they experienced negative gameplay video stimuli relative to 17 participants with low-risk GD. The classification accuracy of the XCSR reached 90% for both negative and positive video stimuli, and nVHF PRV was most frequently used to detect GD risk.

Conclusions

iPRV and IF_resp can be used to detect GD and analyze the autonomic mechanism of individuals with GD.

Gaming to relieve tension or anxiety and associations with health functioning, substance use and physical violence in high school students

Gaming is popular among youth and gaming disorders have been introduced recently into psychiatric nomenclature systems. Motivations underlying gaming may include involvement to reduce negative emotional states and thus may link to psychiatric and overall health. Thus, the extent to which adolescents engage in gaming to relieve anxiety warrants additional investigation. Data from 2005 Connecticut high-school students were used to examine how adolescents who reported gaming to relieve tension or anxiety differed from those who reported gaming but not to relieve tension or anxiety on measures of demographics, academic performance, general health, extracurricular activities, dysphoria/depression symptoms, substance use, and aggressive or violent behaviors. Chi-square analyses and binomial and multinomial logistic regression models were conducted. Gaming to relieve anxiety was more prevalent in boys and Hispanic and Asian adolescents and associated with less extracurricular involvement, poorer academic performance, increased cigarette and other drug use, problematic internet use, and depression. Participants with gaming to relieve tension or anxiety were also more likely to report weapon-carrying, missing school because they felt unsafe, having been threatened with a weapon, having engaged in physical fights, and having experienced injuries from fights. As gaming to relieve anxiety was related to mental-health- and functioning-related measures, additional research is needed to examine the precise natures of these relationships and to translate the information into improved intervention strategies.

Dorsal and ventral striatal functional connectivity shifts play a potential role in internet gaming disorder

Animal models suggest transitions from non-addictive to addictive behavioral engagement are associated with ventral-to-dorsal striatal shifts. However, few studies have examined such features in humans, especially in internet gaming disorder (IGD), a proposed behavioral addiction. We recruited 418 subjects (174 with IGD; 244 with recreational game use (RGU)). Resting-state fMRI data were collected and functional connectivity analyses were performed based on ventral and dorsal striatal seeds. Correlations and follow-up spectrum dynamic causal model (spDCM) analyses were performed to examine relationships between the ventral/dorsal striatum and middle frontal gyrus (MFG). Longitudinal data were also analysed to investigate changes over time. IGD relative to RGU subjects showed lower ventral-striatum-to-MFG (mostly involving supplementary motor area (SMA)) and higher dorsal-striatum-to-MFG functional connectivity. spDCM revealed that left dorsal-striatum-to-MFG connectivity was correlated with IGD severity. Longitudinal data within IGD and RGU groups found greater dorsal striatal connectivity with the MFG in IGD versus RGU subjects. These findings suggest similar ventral-to-dorsal striatal shifts may operate in IGD and traditional addictions.

In order to shed light on the underlying neural mechanisms of internet gaming disorder (IGD), Dong et al collected longitudinal resting-state fMRI data from participants with IGD or those who partake in recreational game use. They demonstrated that, consistent with animal models of addiction, dorsal and ventral striatal functional connectivity shifts appeared to play a potential mechanistic role in IGD.

Large-scale network dysfunction in youths with Internet gaming disorder: a meta-analysis of resting-state functional connectivity studies

Internet gaming disorder (IGD) has been defined as a specific behavioral disorder, associated with abnormal interactions among large-scale brain networks. Researchers have sought to identify the network dysfunction in IGD using resting-state functional connectivity (rsFC). However, results across studies have not reached an agreement yet and the mechanism remains unclear. The present research aimed to investigate network dysfunction in IGD through a meta-analysis of rsFC studies. Twenty-two seed-based voxel-wise rsFC studies from 25 publications (594 individuals with IGD and 496 healthy controls) were included. By categorizing seeds into seed-networks based on their location within a prior functional network parcellations, we performed a Multilevel kernel density analysis (MKDA) within each seed-network to identify which brain systems showed abnormal interaction with particular seed-network in individuals with IGD. Compared to healthy control groups, individuals with IGD exhibited significant hypoconnectivity within the default mode network, and enhanced connectivity between the default mode network and insula within the ventral attention network. IGD was also associated with increased connectivity between the ventral attention network and somatomotor regions. Furthermore, the IGD groups showed hyperconnectivity between the limbic network and regions of the frontoparietal network. The results suggest that individuals with IGD show large-scale functional network alteration which underpins their core symptoms including poor emotional competence, cue-reactivity and craving, habitual addictive behaviors and impaired executive control. Whether the compensation mechanism exists in IGD is discussed, and further research is needed. The findings provide a neurocognitive network model of IGD, which may serve as functional biomarkers for IGD and have potentials for development of effective diagnosis and therapeutic interventions.

Reduced frontostriatal functional connectivity and associations with severity of Internet gaming disorder

Cognitive, functional, and structural brain factors involving frontal executive and striatal reward networks have been implicated in Internet gaming disorder (IGD). However, frontostriatal network connectivity and its association with addiction severity are poorly understood in IGD. Resting-state fMRI data from 337 subjects (130 with IGD, 207 with recreational game use [RGU]) were collected. Striatal-cortical communications were measured with resting-state functional connectivity (FC) using coherent spontaneous fluctuations in the blood-oxygenation-level-dependent fMRI signal. Correlations were calculated between FC measures and IGD-related assessments (addiction severity and craving scores). Decreased FC was predominantly observed in IGD subjects, with IGD subjects showing decreased FC between the putamen and superior frontal gyrus (SFG), middle frontal gyrus (MFG), and inferior frontal gyrus (IFG) and the ventral striatum and IFG, superior temporal gyrus, and MFG. Disorder severity and craving scores were negatively correlated with FC between striatal and frontal brain regions. Associations between diminished FC in corticostriatal circuitry and clinical features (IGD craving, severity) suggest potential therapeutic targets for neuromodulation treatments. The extent to which frontostriatal circuits involving executive control over reward processes may be altered to treat IGD warrants additional study.

Internet gaming disorder impacts gray matter structural covariance organization in the default mode network

INTRODUCTION

Although previous studies have revealed that dysfunctional brain organization is associated with internet gamingdisorder (IGD), the neuroanatomical basis that underlies IGD remains elusive. In this work, we aimed to investigate gray matter (GM) volume alterations and structural covariance patterns in relation to IGD severity.

METHODS

Structural magnetic resonance imaging data were acquired from two hundred and thirty young adults encompassing a wide range of IGD severity. Voxel-based morphometry (VBM) analysis was applied to examine GM volume changes associated with IGD severity. Furthermore, the organization of whole-brain structural covariance network (SCN) was analyzed using the regions identified as seeds from VBM analysis.

RESULTS

Individuals with greater IGD severity had increased GM volumes in the midline components of the default mode network (DMN), namely, the right medial prefrontal cortex (mPFC) and precuneus. More importantly, the SCN results revealed impaired patterns of structural covariance between the DMN-related regions and areas associated with visuospatial attention and reward craving processing as the addiction severity of IGD worsened.

LIMITATIONS

Only young Chinese adults were enrolled in our study andthe extent to which findings generalize to samples in other age groups and diverse cultures is unclear.

CONCLUSIONS

These results showed volume expansion of the DMN components and its weakened structural association with visuospatial attention and motivational craving regions with increasing IGD severity. This study deepens our understanding of the underlying neuroanatomical correlates of IGD, which may help to explain why some individuals are more vulnerable to compulsive gaming usage than others.

The gray matter volume in superior frontal gyrus mediates the impact of reflection on emotion in Internet gaming addicts

Internet gaming disorder (IGD) is becoming a prevalent mental health concern around the world. However, the relationship among brain gray matter volume (GMV), emotion induced by decision-making and the level of reflection in IGD participants has not been fully elucidated to date. The current study aimed to explore this issue by combining a sequential decision task and voxel-based morphometry. Twenty-six IGD participants and 28 demographically matched healthy controls were recruited. After collecting Rumination-Reflection questionnaire data and high-resolution T1-weighted MRI data, participants were asked to complete a sequential decision task. The results demonstrated that compared to healthy controls, IGD participants exhibited significantly decreased GMV in the superior frontal gyrus (SFG). Moreover, GMV in the SFG of IGD participants fully mediated the impact of reflection level on the emotion of loss outcome during the sequential decision task. These results indicate that IGD is associated with reduced GMV in the SFG, and this structural change in IGD contributes to a particular relationship between the level of reflection and regret emotion for loss outcome in the sequential decision task.

The imbalance between goal-directed and habitual systems in internet gaming disorder: Results from the disturbed thalamocortical communications

BACKGROUND

Converging evidence has identified the imbalance between goal-directed systems and habitual systems in the addiction process. The thalamocortical loop plays an important role in the habitual/goal-directed system. However, little is known about the role of the thalamus in goal-directed and habitual systems in Internet gaming disorder (IGD) patients. This study investigated whether thalamocortical circuit was disrupted and how they affected goal-directed and habitual behaviors in IGD patients.

METHODS

This is a functional magnetic resonance imaging (fMRI) study. Twenty-five IGD patients and 25 matched recreational game users (RGUs) were scanned when they were in a resting state and were performing an instrumental learning task to obtain behavioral data related to habitual/goal-directed behavior. We used the whole-brain seed-based functional connectivity (FC) of the four thalamic nuclei (bilateral) and correlation analyses to examine the thalamocortical loop difference and relationship with habitual/goal-directed performance.

RESULTS

Compared with RGUs, IGD patients demonstrated significantly increased FC between the left midline nucleus (MN) and the right postcentral gyrus (PCG), and between the pulvinar and medial frontal gyrus (MFG). Correlation results showed that within the IGD group, the correct response rates of the participants to inconsistent stimulus-result pairs were positively correlated with the FC between the pulvinar and MFG. Inhibition-control scores were negatively correlated with the FC between the left MN and the PCG.

CONCLUSIONS

IGD patients showed disrupted thalamocortical communication that could further result in an imbalance between the goal-directed and habitual systems in IGD patients. These findings provide more information about the involvement of the thalamus in the pathophysiology of IGD, and as potential circuit-level biomarkers of IGD patients, these circuit alterations may be useful in treatment development and in monitoring treatment outcomes.

Problematic internet gaming in adolescents, and its relationship with emotional regulation and perceived social support

Technological developments and the increased use of the internet have created some risks for adolescents, including problematic internet gaming (PIG). The aim of this study is to investigate the role of age, gender, emotional dysregulation and perceived social support in PIG. The study was conducted with 1,291 adolescents. Participants completed the game addiction scale (GAS), difficulties in emotion regulation scale (DERS), and multidimensional scale of perceived social support (MSPSS) under the observation of their teachers. According to the results of the GAS, participants were divided into two groups: those with PIG and those without PIG. The effect of age, gender, DERS scores, and MSPSS scores on PIG was investigated using stepwise logistic regression analysis. The mean age of participants was 14.7 years and the frequency of PIG was 13.5% (n = 144). The frequency of PIG was significantly higher in males than in females. The results showed that male gender, high emotional dysregulation and low perceived social support were significantly associated with PIG. The present study indicate that PIG is highly observed in adolescents, especially in males, and as in other behavioral addictions, emotional dysregulation and perceived social support can play an important role in PIG.

Attenuated self-serving bias in people with internet gaming disorder is related to altered neural activity in subcortical-cortical midline structures

BACKGROUND

To protect and maintain the positivity of self-concept, normal people usually show a self-serving bias (internal attribution of positive events and external attribution of negative events) by the motives of self-enhancement and self-protection. Additionally, self-serving assessments predominantly activate the subcortical-cortical midline structures (CMS) in healthy individuals. However, little is known about self-serving bias and its underlying neural correlates among individuals with Internet gaming disorder (IGD).

METHODS

Twenty-four participants with IGD and 25 recreational Internet gaming users (RGUs) were scanned while attributing the causes of positive/negative self- and other-related events that could occur in both the game-world and real-world contexts. Region-of-interest (within CMS regions) and parametric analysis were performed to investigate the neural correlates of self-serving bias in IGD.

RESULTS

Behaviorally, the IGD participants attributed more negative and fewer positive events to themselves than RGU participants in both contexts. Neurally, during the attributions of negative events, the IGD participants exhibited increased ventromedial prefrontal cortex (vmPFC) activation in both contexts compared with RGU participants. Higher vmPFC activation was associated with weaker self-protective motivation in the IGD group. Meanwhile, during the attributions of positive events, the IGD participants exhibited decreased precuneus/posterior cingulate cortex activation in the real world compared with RGU participants. Parametric analysis showed a reduced positive correlation between precuneus activation and self-attribution ratings of positive events in the real world in the IGD group relative to the RGU group.

CONCLUSION

These results suggest that individuals with IGD show an attenuated self-serving bias and altered brain activity within CMS regions involved in self-attribution, providing evidence for the negative self-concept and weakened abilities in both self-enhancement and self-protection in IGD.