Submitted:
16 December 2025
Posted:
17 December 2025
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Abstract
Keywords:
1. Introduction
2. Background on Internet Gaming Disorder
2.1. Definition and Diagnostic Criteria
2.2. Epidemiology and Prevalence
2.3. Etiological Models
2.4. Current Treatments and Limitations
3. Background on Large Language Models
3.1. What Are Large Language Models?
3.2. Mechanisms and Capabilities
3.3. LLMs in Mental Health Applications
3.4. Advantages and Limitations in Mental Health
4. Integrating LLMs with Internet Gaming Disorder
4.1. Diagnostic and Screening Applications
4.2. Therapeutic Interventions
4.3. Monitoring and Relapse Prevention
4.4. Research and Data Analysis
4.5. Case Studies and Preliminary Evidence
5. Challenges and Ethical Considerations
5.1. Ethical Concerns
5.2. Technical Challenges
5.3. Clinical Limitations
6. Future Directions
6.1. Hybrid Human-AI Therapeutic Models
6.2. Multimodal and Immersive Integrations
6.3. Longitudinal Research and Validation
6.4. Ethical Frameworks and Policy Development
6.5. Preventive and Public Health Applications
6.6. Limitations of This Review
7. Conclusion
Funding
Conflicts of Interest
Abbreviations
| ADHD | Attention-Deficit/Hyperactivity Disorder |
| AI | Artificial Intelligence |
| ALFF | Amplitude of low-frequency fluctuation |
| APA | American Psychiatric Association |
| AUD | Alcohol Use Disorder |
| BLEU | Bilingual Evaluation Understudy (MT metric) |
| CBT | Cognitive Behavioral Therapy |
| COVID-19 | Coronavirus Disease 2019 |
| DPIA(s) | Data Protection Impact Assessment(s) |
| DSM-5 | Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition |
| EHR | Electronic Health Record |
| EU | European Union |
| FUTURE-AI | International consensus guideline for trustworthy, deployable AI |
| fNIRS | Functional near-infrared spectroscopy |
| GDPR | General Data Protection Regulation |
| GPT-4 | Generative Pre-trained Transformer 4 |
| ICD-11 | International Classification of Diseases, 11th Revision |
| IGD | Internet Gaming Disorder |
| IGDS9-SF | Internet Gaming Disorder Scale–Short Form (9-item) |
| IGDT-10 | Ten-Item Internet Gaming Disorder Test |
| LLM(s) | Large Language Model(s) |
| LMM(s) | Large Multimodal Model(s) |
| NLP | Natural Language Processing |
| PRISMA | Preferred Reporting Items for Systematic Reviews and Meta-Analyses |
| RCT(s) | Randomized Controlled Trial(s) |
| ReHo | Regional Homogeneity |
| RLHF | Reinforcement Learning from Human Feedback |
| SFT | Supervised Fine-Tuning |
| SVM | Support Vector Machine |
| VBM | Voxel-Based Morphometry |
| VR/AR | Virtual Reality / Augmented Reality |
| WHO | World Health Organization |
Appendix A. Expanded Details for IGD-Specific AI/ML Studies
A1. Strojny et al., 2024 — Text/NLP Screening (JMIR Serious Games)
- Model/training: Transformer embeddings (HerBERT) + ridge regression; no task-specific fine-tuning.
- Dataset: n = 417 gamers after quality control; four open-ended responses + Gaming Disorder Test.
- Validation/performance: Pearson r = 0.476 using all four responses; single-item r = 0.274–0.406.
- Open vs closed: Used an open-source LM (HerBERT); code/data not publicly released.
- Limitations: Correlational (screening signal, not diagnosis); self-report criterion; no external validation.
A2. Cho et al., 2024 — School Digital Phenotyping (JMIR Mental Health)
- Model/training: Multiple regression with bootstrapping + MANOVA; interpretability prioritized over prediction.
- Dataset: n = 168 adolescents (85 IGD, 83 non-IGD); tablet sensor metrics during classes.
- Validation/performance: Five digital markers explained 23% of IGDS variance; group differences ~Cohen’s d ≈ 0.40 (moderate).
- Open vs closed: Methods published; no public dataset/model.
- Limitations: Screening (not confirmatory diagnosis); single-school context; no ML classifier.
A3. Lee et al., 2024 — EEG + Neuropsychology Classification (Comprehensive Psychiatry)
- Model/training: L1-SVM, Random Forest, and L1-logistic regression; unimodal EEG, unimodal neuropsych, and multimodal feature sets.
- Dataset: IGD n = 67, AUD n = 58, HC n = 66; resting-state EEG + psychometrics.
- Validation/performance: Best model (logistic regression, multimodal) for IGD vs AUD: accuracy = 71.2%; salient delta/beta source connectivity + demographics.
- Open vs closed: Open-access article; code/data not released.
- Limitations: Case–control; no external validation; limited clinical utility metrics (e.g., AUC, calibration).
A4. Wang et al., 2023 — fNIRS Deep Learning (Biomedizinische Technik/Biomedical Engineering)
- Model/training: Prefrontal fNIRS during stop-signal task; seven ML/DL algorithms compared; 2D-CNN performed best.
- Dataset: n = 40 (24 IGD, 16 HC).
- Validation/performance: Hold-out accuracy = 87.5% (2D-CNN), outperforming traditional ML.
- Open vs closed: Methods described; code/data not public.
- Limitations: Small sample; single site; hold-out split (no cross-site external validation).
A5. Song et al., 2021 — Resting-State fMRI Connectome SVM (Addiction Biology)
- Model/training: Modified connectome-based predictive modeling (CPM) with SVM; classification + regression.
- Dataset: IGD n = 72, HC n = 41; resting-state fMRI.
- Validation/performance: DMN-based model accuracy = 78.76% (balanced accuracy = 75.46%; sensitivity = 63.41%; specificity = 87.5%); DMN features also predicted CIAS severity (r = 0.44).
- Open vs closed: Data available on request; MATLAB scripts mentioned; no public repo.
- Limitations: Predominantly young adult males; no external replication; cultural/generalizability considerations.
A6. Ye et al., 2022 — MVPA Predicting IGD Severity (Journal of Affective Disorders)
- Model/training: MVPA on resting-state fMRI features (ReHo, ALFF) to predict continuous IGD severity.
- Dataset: n = 402 participants spanning the IGD severity continuum.
- Validation/performance: Neural patterns significantly predicted severity; high-weighted regions then probed by graph/causality analyses.
- Open vs closed: No public code/data noted.
- Limitations: Cross-sectional; thresholds for clinical decision-making not established; potential site/scan heterogeneity.
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| Study (Year) | AI Method & Training | Sample & Data | Performance Metrics | Model Open-Source? |
|---|---|---|---|---|
| Strojny et al., 2024 | NLP (Transformer + Ridge Regression) – Supervised learning on open-ended text. Pretrained HerBERT transformer encoder for embeddings (no fine-tuning). | 417 gamers (online survey) – 4 free-text responses + IGD scale. | Correlation: Predicted vs. actual IGD scores r = 0.476 (multi-response model). | Yes (Partially) – Used open pretrained transformer (HerBERT); model code for research only (not a deployed tool). |
| Cho et al., 2024 | Digital phenotyping (Regression) – Multivariate linear models with cross-validation. No ML fine-tuning (focused on interpretability). | 168 students (53% female, age 13–14) – Tablet sensor metrics during classes. | Variance explained: 23% of IGD score by 5 digital markers; significant group differences (avg. Cohen’s d ≈ 0.4). | No – Developed as part of proprietary school system (Dr. Simon). |
| Lee et al., 2024 | Multimodal ML (EEG + Surveys) – Supervised classifiers (Logistic Reg., SVM, Random Forest) on neural and clinical features. Models trained with L1 regularization (feature selection). | 191 adults (67 IGD, 58 AUD, 66 healthy) – Resting EEG signals + psychometric data. | Accuracy: 71.2% for IGD vs. AUD classification (best model); salient features: abnormal beta/delta EEG connectivity in IGD. | No – Research-only model (open-access publication, but no released software). |
| Song et al., 2021 | Connectome SVM (fMRI) – Modified CPM algorithm using Support Vector Machine. Supervised learning on brain network matrices. | 113 young adults (72 IGD, 41 healthy) – Resting-state fMRI connectivity data. | Accuracy: 78.76% (balanced accuracy = 75.46%; sensitivity = 63.41%; specificity = 87.5%); DMN features also predicted CIAS severity (r = 0.44). | No – Not open-source (analysis code not public; no deployment). |
| Wang et al., 2023 | Deep Neural Network (2D-CNN) – Supervised convolutional network trained on fNIRS time-series images. Compared against other ML/DL algorithms. | 40 subjects (24 IGD, 16 healthy) – Prefrontal fNIRS signals during stop-signal inhibition task. | Accuracy: 87.5% (IGD vs. healthy, with 2D-CNN – highest among models); outperformed traditional ML classifiers. | No – Custom experimental model (not released; closed-source prototype). |
| Ye et al., 2022 | MVPA (Multi-voxel Pattern Analysis) – Supervised pattern recognition on fMRI features. Trained to predict continuous IGD severity (regression). | 402 individuals (mixed gaming habits; spectrum of IGD severity) – Resting fMRI metrics (ReHo, ALFF). | Outcome: Brain patterns significantly predicted IGD severity (p < 0.001); identified key regions (prefrontal cortex) correlated with symptom level. | No – Research analysis only (no deployed model; code not publicly provided). |
| Care stage | LLM-enabled task | Primary risks | Safeguards / implementation notes | Implementation readiness |
|---|---|---|---|---|
| Screening / Early detection | Triage chat + short screener routing (e.g., IGDS9-SF prompts, risk-language detection) | False positives/negatives; misclassification of subthreshold cases | Validate against gold standards; calibrate thresholds; human review for positives | Medium |
| Diagnostic assessment & comorbidity review | Structured history; comorbidity prompts (ADHD/AUD/anxiety/depression) | Overconfidence; hallucinations; minority bias | Structured prompts; require citations; clinician-in-the-loop; bias testing | Low–Medium |
| Psychoeducation & motivational enhancement | Explain IGD mechanisms; goals; MI-style reflections | Inaccurate advice; uncalibrated empathy; “therapy” drift | Restrict scope; scripted safety language; clear AI disclosures | Medium |
| CBT skills coaching & relapse prevention | Homework adherence; cognitive restructuring; craving plans; play-time contracts | Over-reliance; poor escalation | Escalation trees; relapse signals reviewed by clinician; EHR integration | Low–Medium |
| Continuous monitoring | Summarize diaries/telemetry; flag risk phrases; weekly reports | Privacy leakage; false alarms; clinician burden | Minimize data; privacy-by-design; precision tuning; opt-in | Low |
| Crisis & safety (adjunct only) | Detect suicidality cues; present resources; encourage contacting humans | Unsafe responses; wrong numbers; delayed escalation | Location-aware hotlines; immediate human handoff; prohibit “how-to”; red-team tests | Low |
| Governance & compliance | Consent logging; model versioning; bias/robustness reports; DPIAs | Non-compliance; poor traceability | Follow WHO LMM guidance; EU AI Act staged timelines; audit trails; human accountability | Medium |
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