Diffusion tensor imaging of the structural integrity of white matter correlates with impulsivity in adolescents with internet gaming disorder

Gaming disorder: Neural mechanisms and ongoing debates

Background and aims

The inclusion of gaming disorder as a new diagnosis in the 11th revision of the International Statistical Classification of Diseases (ICD-11) has caused ongoing debate. This review aimed to summarise the potential neural mechanisms of gaming disorder and provide additional evidence for this debate.

Methods

We conducted a comprehensive literature review of gaming disorder, focusing on studies that investigated its clinical characteristics and neurobiological mechanisms. Based on this evidence, we further discuss gaming disorder as a psychiatric disorder.

Results

The present review demonstrated that the brain regions involved in gaming disorder are related to executive functioning (e.g., anterior cingulate cortex and dorsolateral prefrontal cortex), reward systems (e.g., striatum and orbitofrontal cortex), and emotional regulation (e.g., insula and amygdala). Despite the inclusion of gaming disorder in the ICD-11, the debate remains on the benefits and harms of classifying it as a mental health disorder. Opponents argue that the current manifestations that support gaming disorder as a psychiatric disorder remain inadequate, it could cause moral panic among healthy gamers, and that the label of gaming disorder is stigmatising.

Discussion

Evidence suggests that gaming disorder shares similar neurobiological alterations with other types of behavioural and substance-related addictions, which further supports gaming disorder as a behavioural addiction. Ongoing debates on whether gaming disorder is a psychiatric disorder push for further exploring the nature of gaming disorder and resolving this dilemma in the field.

White matter microstructural changes in internet addiction disorder: A systematic review of diffusion tensor imaging studies

Diffusion tensor imaging (DTI) is a kind of magnetic resonance imaging (MRI) modality that helps designate tracts with brain microstructural changes. Internet gaming disorder (IGD) is an internet addiction that can cause many social and personality problems, such as problems in social communication, anxiety, and depression. There are several pieces of evidence showing the impact of this condition on brain regions, and many studies have investigated DTI measurements in these individuals. Therefore, we decided to systematically review the studies that have reported DTI parameters in IGD individuals. We searched the PubMed and Scopus databases to find relevant articles. Two reviewers separately screened the studies, and finally, 14 articles, including diffusion and network studies, were found eligible for our systematic review. Most of the studies reported findings on FA, showing an increase in the thalamus, anterior thalamic radiation, corticospinal tract, and inferior longitudinal fasciculus (ILF), while other regions mentioned in the studies demonstrated inconsistent findings. Moreover, in network studies, IGD individuals showed a decrease in nodal and global efficiencies. In conclusion, our study illuminates the neuropsychological basis of this condition and suggests that internet gaming can correlate with microstructural abnormalities in the central nervous system. Some correlate with the characteristics of online gaming, the addiction state, and the illness's duration.

Neuroimaging findings in adolescent gaming disorder: a systematic review

OBJECTIVES

Gaming disorder is a growing concern affecting adolescents, exacerbated by the impact of recent COVID-19 restrictions. The World Health Organization has recently included gaming disorder in the 11th International Classification of Diseases (ICD-11). However, there is still an ongoing debate about the validity and reliability of the proposed clinical criteria, despite growing neurobiological evidence in this cohort. Systematic reviews in this area have focused mainly on adults or mixed adult/adolescent populations. Therefore, this systematic review explored the neuroimaging literature in adolescents (under 18 years old) with gaming disorder.

METHODS

Using PRISMA 2020 guidelines, 3288 primary studies were identified from PubMed, CINAHL Plus, PsycINFO and Web of Science. After applying inclusion and exclusion criteria (appropriate title, abstract, comparison group used within study, English-language, neuroimaging and mean age under 18), 24 studies were included in this review.

RESULTS

Functional and structural brain alterations in adolescent gaming disorder were noted across several imaging modalities, including electroencephalogram (EEG), functional magnetic resonance imaging (fMRI) and structural magnetic resonance imaging (MRI). Compared with healthy controls, adolescents with gaming disorder demonstrated neurological changes comparable to substance addiction, namely impairments in emotional regulation, reward-seeking, inhibition and increased risky decision-making. Positive brain adaptations in the areas of visuospatial processing and memory were observed.

CONCLUSIONS

A number of key brain regions are affected in adolescent gaming disorder. These findings can help clinicians understand adolescent presentations with gaming disorder from a neurobiological perspective. Future studies should focus on forming a robust neurobiological and clinical framework for adolescent gaming disorder.

“Game (not) Over”: A Systematic Review of Video Game Disorder in Adolescents

This study aims to characterize video game use disorder in adolescents, identifying the particularities of those who present it, its effects at the brain level, related factors, and existing measurement instruments. A systematic review of the scientific publications available in Scopus was carried out, between the period 2014-2018 on video game use disorder in adolescents. Adolescents with this disorder are characterized by being mostly men, spending more time daily and weekly playing than adolescents without this disorder, showing diverse symptoms in the behavioral, affective, and cognitive areas. At brain level, it is referred that in this disorder there is an increase and decrease in the activation of specific areas of the brain. Likewise, the presence of some psychological disorder and impulsivity are considered factors that increase the risk of suffering from it. However, there are protective factors as school commitment and parental supervision, among others. How to cite: Rojas-Jara, C., Polanco-Carrasco, R., Navarro-Castillo, R., Faúndez-Castillo, F., & Chamorro-Gallardo, M. (2022). “Game (not) Over”: A Systematic Review of Video Game Disorder in Adolescents. Revista Colombiana de Psicología, 31(2), 45-64. https://doi.org/10.15446/rcp.v31n2.90741

MRI-Based Radiomic Machine-Learning Model May Accurately Distinguish between Subjects with Internet Gaming Disorder and Healthy Controls

Purpose To identify cerebral radiomic features related to the diagnosis of Internet gaming disorder (IGD) and construct a radiomics-based machine-learning model for IGD diagnosis. Methods A total of 59 treatment-naïve subjects with IGD and 69 age- and sex-matched healthy controls (HCs) were recruited and underwent anatomic and diffusion-tensor magnetic resonance imaging (MRI). The features of the morphometric properties of gray matter and diffusion properties of white matter were extracted for each participant. After excluding the noise feature with single-factor analysis of variance, the remaining 179 features were included in an all-relevant feature selection procedure within cross-validation loops to identify features with significant discriminative power. Random forest classifiers were constructed and evaluated based on the identified features. Results No overall differences in the total brain volume (1,555,295.64 ± 152,316.31 mm3 vs. 154,491.19 ± 151,241.11 mm3), total gray (709,119.83 ± 59,534.46 mm3 vs. 751,018.21 ± 58,611.32 mm3) and white (465,054.49 ± 51,862.65 mm3 vs. 470,600.22 ± 47,006.67 mm3) matter volumes, and subcortical region volume (63,882.71 ± 5110.42 mm3 vs. 64,764.36 ± 4332.33 mm3) between the IGD and HC groups were observed. The mean classification accuracy was 73%. An altered cortical shape in the bilateral fusiform, left rostral middle frontal (rMFG), left cuneus, left parsopercularis (IFG), and regions around the right uncinate fasciculus (UF) and left internal capsule (IC) contributed significantly to group discrimination. Conclusions: Our study found the brain morphology alterations between IGD subjects and HCs through a radiomics-based machine-learning method, which may help revealing underlying IGD-related neurobiology mechanisms.

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.

Cerebral microstructural abnormalities in impulsivity: a magnetic resonance study

Studies that investigated neurobiological parameters subtended to impulsivity trait found their relationship with structural and functional brain alterations. No studies investigated the white matter microstructural attributes of impulsivity in a large sample of healthy subjects. In the present study 1007 subjects from Human Connectome Project public dataset were divided in two groups, impulsive and not impulsive, basing on Delay Discounting task score. For both groups brain morphometric and microstructural characteristics were investigated. A t-test (correct for multiple comparisons) was performed for each brain parcel and impulsivity measure. Magnetic resonance diffusion images were pre-processed and selected to perform a voxelwise analysis on the fractional anisotropy (FA) maps between impulsive and not impulsive groups. Group analysis showed significant differences in morphometric brain data mainly for temporal and frontal lobes. The impulsive group presented higher FA values in four regions: bilateral medial lemniscus and midbrain reticular formation, right superior longitudinal fasciculus, left forceps major, right corticospinal tract. Not impulsive group showed higher FA values in two significant regions: right and left anterior thalamus radiation. Concluding, macroscopic and microstructural brain alterations were assessed, identifying new neuroanatomical substrates for multidimensional impulsivity construct in a large sample of healthy subjects.

Impulsivity and Response Inhibition Related Brain Networks in Adolescents With Internet Gaming Disorder: A Preliminary Study Utilizing Resting-State fMRI

Background and Aims: Internet gaming disorder (IGD), as a relapse disease, has become a common mental health problem among Asian teenagers. Functional connections in the prefrontal lobo-striatum affect changes in impulsivity and inhibition. Therefore, exploration of the directional connections of the relevant brain regions in the prefrontal-striatal circuit and the synchronization level of the two hemispheres will help us to further understand the neural mechanism of IGD, which can provide guidance for the development of prevention and intervention strategies. Methods: Twenty-two adolescents with IGD, recruited through various channels, composed the IGD group. Twenty-six subjects, matching age, gender, and education level, were included in a recreational internet game users (RGUs) control group. Impulsivity and response inhibition were tested via general questionnaire, the Internet Addiction Test (IAT), the Barratt impulsivity scale-11 (BIS-11), and a Stroop color-word task. A Granger causality analysis (GCA) was used to calculate the directional connection between the prefrontal and striatum with the dorsolateral prefrontal cortex (DLPFC) as a region of interest (ROI). We chose voxel-mirrored homotopic connectivity (VMHC) to determine brain hemisphere functional connectivity in the prefrontal-striatal circuits. Results: We found significant differences in impulsivity between the IGD group and RGU group, with members of the IGD group exhibiting higher impulsivity. Additionally, the response inhibition of adolescents with IGD in the Stroop color-word task was impaired. There was a significant difference in the directed connection of the left DLPFC and dorsal striatum between the IGD group and the RGU group. Conclusions: This study confirmed the role of prefrontal-striatal circuits in the neural mechanism of IGD in adolescents. In the IGD group, bilateral cerebral medial orbitofrontal cortex (mOFC) synchronization was significantly reduced, which indicated that mOFC signal transmission in both hemispheres of the brain might be affected by impulse behavior and impaired response inhibition.

Investigation of structure-function correlation among the young offspring of patients with bipolar disorder

Bipolar disorder (BD) has been associated with impaired executive functioning and integrity of fronto-limbic white matter tracts. The evaluation of these factors in young offspring of patients with BD (BDoff) as a high-risk group offers an opportunity to investigate factors that could predict vulnerability to the disorder. This study aims to examine the correlation between neurocognition and neuroimaging findings to evaluate the potential for these findings as biomarkers for the early recognition of BD. We enrolled BDoff (n = 16) who were aged between 12 and 18. Participants were assessed using clinical and neurocognitive tests. In addition, structural brain magnetic resonance and diffusion tensor imaging data were obtained. Mean fractional anisotropy (FA) and mean diffusivity (MD) values of the superior longitudinal fasciculus (SLF) and cingulum were extracted and correlations with neuropsychological data were analyzed. FA values in the SLF were negatively correlated with Stroop interference, the Wisconsin Card Sorting Test, and the Trail Making Test (B-A) scores. MD values in the cingulum were inversely correlated with the Child and Youth Resilience Measure and positively correlated with higher scores on the Barratt Impulsiveness Scale-Attentional. These findings provide a link between features of the brain and cognitive dysfunction in BDoff.

Increase of orexin A in the peripheral blood of adolescents with Internet gaming disorder

BACKGROUND AND AIMS

Overindulgence in Internet gaming, which is related to rapid development of the online game industry, can cause a psychiatric disorder known as Internet gaming disorder (IGD). The number of adolescents with IGD is on the rise in countries with developed Internet technologies, such as South Korea. Therefore, it is important to develop biomarkers to detect patients at high risk of IGD. This study investigated expression levels of proteins in the blood of adolescents to provide insight into the development of biomarkers.

METHODS

We collected blood samples from 73 subjects [40 healthy adolescents (Internet gaming control, IGC) and 33 adolescents with IGD] between 13:00 and 15:00. We analyzed the expression levels of orexin A, oxytocin, cortisol, melatonin, BDNF, sICAM-1, RANTES, and NCAM using multiplex assay kits.

RESULTS

Orexin A was significantly (p = .016) elevated in the IGD group and the expression levels of melatonin tended to be higher (p = .055) in the IGD group. On the other hand, increased Internet gaming time in the IGD group was negatively correlated (p = .041) with expression of BDNF. On the contrary, sICAM-1 associated with inflammation exhibited the tendency of the positive correlation (p = .073) with Internet gaming time in the IGD group.

DISCUSSION AND CONCLUSIONS

We identified elevation of orexin A in the peripheral blood of adolescents with IGD and a negative correlation between Internet gaming time and BDNF in adolescents with IGD. Our results provide useful information to understand the pathophysiology of IGD in adolescents.

Microstructural changes and internet addiction behaviour: A preliminary diffusion MRI study

Internet addiction (IA) is a major health problem and is associated with comorbidities like insomnia and depression. These consequences frequently confound neuroanatomical correlates of IA in those suffering from it. We enrolled a number of 123 healthy native German-speaking adults (53 male, mean age: 36.8 ± 18.86) from the Leipzig Study for Mind-Body-Emotion Interactions (LEMON) database, for whom diffusion MRI data, internet addiction test, brief self-control scale (SCS), coping orientations to problems experienced (COPE), and depression scores were available. DMRI connectometry was used to investigate white matter microstructural correlates of the severity of internet addiction identified through IAT, in a group of healty young individuals. A multiple regression model was adopted with age, gender, SCS total score, COPE total score, and BDI-sum as covariates to track white matter fibers in which connectivity was associated with IAT. The connectometry analysis identified a direct correlation between connectivity in the splenium of corpus callosum (CC), parts of bilateral corticospinal tracts (CST), and bilateral arcuate fasciculi (AF) (FDR = 0.0023001), and an inverse correlation of the connectivity in the genu of CC and right fornix (FDR = 0.047138), with the IAT score in healthy adults. We suggest connectivity in the CC and CST as well as fornix and AF to be considered as microstructural biomarkers of predisposition to IA in healthy population.

White matter abnormalities in depression: A categorical and phenotypic diffusion MRI study

Mood depressive disorder is one of the most disabling chronic diseases with a high rate of everyday life disability that affects 350 million people around the world. Recent advances in neuroimaging have reported widespread structural abnormalities, suggesting a dysfunctional frontal-limbic circuit involved in the pathophysiological mechanisms of depression. However, a variety of different white matter regions has been implicated and is sought to suffer from lack of reproducibility of such categorical-based biomarkers. These inconsistent results might be attributed to various factors: actual categorical definition of depression as well as clinical phenotype variability. In this study, we 1/ examined WM changes in a large cohort (114 patients) compared to a healthy control group and 2/ sought to identify specific WM alterations in relation to specific depressive phenotypes such as anhedonia (i.e. lack of pleasure), anxiety and psychomotor retardation –three core symptoms involved in depression. Consistent with previous studies, reduced white matter was observed in the genu of the corpus callosum extending to the inferior fasciculus and posterior thalamic radiation, confirming a frontal-limbic circuit abnormality. Our analysis also reported other patterns of increased fractional anisotropy and axial diffusivity as well as decreased apparent diffusion coefficient and radial diffusivity in the splenium of the corpus callosum and posterior limb of the internal capsule. Moreover, a positive correlation between FA and anhedonia was found in the superior longitudinal fasciculus as well as a negative correlation in the cingulum. Then, the analysis of the anxiety and diffusion metric revealed that increased anxiety was associated with greater FA values in genu and splenium of corpus callosum, anterior corona radiata and posterior thalamic radiation. Finally, the motor retardation analysis showed a correlation between increased Widlöcher depressive retardation scale scores and reduced FA in the body and genu of the corpus callosum, fornix, and superior striatum. Through this twofold approach (categorical and phenotypic), this study has underlined the need to move forward to a symptom-based research area of biomarkers, which help to understand the pathophysiology of mood depressive disorders and to stratify precise phenotypes of depression with targeted therapeutic strategies.

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Mood depressive disorder is one of the most disabling chronic disease.

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Past studies of diffusion analysis had found inconsistent results.

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We analyzed white matter integrity in a large cohort of depressed patients.

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We conducted both categorical and dimensional approaches.

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In the future, these biomarkers could help to develop new therapeutic strategies.

Association Between Specific Internet Activities and Life Satisfaction: The Mediating Effects of Loneliness and Depression

The current study examined the associations between specific Internet activities (online shopping, pornography use, social networking site use, and Internet gaming), life satisfaction, and the mediating effects of loneliness and depression for these associations. Participants were 5,215 students (2,303 male participants, Mage = 16.20 years; ranging in age from 10 to 23 years) from various school types (546 elementary school students, 1710 junior high school students, 688 senior high school students, and 2271 university students) who provided self-report data on demographic variables, online shopping, pornography use, social networking site use, loneliness, depression, and life satisfaction. The results indicated that after controlling for demographic variables (gender and age) (a) loneliness and depression had fully positive mediating effects on the association between social networking site use and life satisfaction; (b) loneliness and depression played fully negative mediating effects on life satisfaction associations with online shopping, pornography use, and Internet gaming. Therefore, loneliness and depression were the underlying mechanisms that caused life satisfaction to be affected by online shopping, pornography use, social networking site use, and Internet gaming.

Diffusion tensor imaging of the structural integrity of white matter correlates with impulsivity in adolescents with internet gaming disorder

INTRODUCTION

Internet gaming disorder (IGD) is usually defined as the inability of an individual to control internet gaming resulting in serious negative consequences, and trait impulsivity has been viewed as a hallmark feature of IGD. Recent studies have suggested that the structural integrity of the white matter (WM) plays an important role in the neuromediation of an individual's impulsivity. However, no study has examined the association between WM integrity and impulsivity in IGD adolescents.

METHODS

In this study, 33 adolescents with IGD and 32 healthy controls (HCs) were recruited, and the intergroup differences in the relationships between impulsivity and fractional anisotropy (FA) values across the whole brain WM were investigated using voxel-wise correlation analyses.

RESULTS

Our results revealed significant intergroup differences in the correlations between impulsivity and the FA values of the right corticospinal tract (CST) and the right occipital WM. Region of interest-based tests revealed that the FA values of these clusters were positive or insignificantly correlated with impulsivity in the IGD adolescents contrasted to the significantly negative correlation in the HCs.

CONCLUSIONS

This altered correlations in the IGD adolescents might reflect potential WM microstructural changes which may be associated with the greater impulsivity of IGD adolescents and provide possible therapeutic targets for interventions in this population.