Light Therapy for Internet Gaming Disorder

Study Overview
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Brief Summary
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This project aims to investigate (1) the efficacy of light therapy on internet gaming disorder (IGD); (2) the underlying neural mechanisms of such efficacy

Official Title
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A Randomized Controlled Double-Blind Trial of Light Therapy for Internet Gaming Disorder

Conditions
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Internet Gaming Disorder, Light Therapy

Intervention / Treatment
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* Other: Light therapy
* Other: Light placebo therapy
* Other: Emotion Bias Modification Training


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: the 5th edition of Diagnostic and Statistical Manual of Mental Disorders (DSM-5 ) recommended diagnosis of Internet gaming disorder; the scores of the Young-Internet addiction Test ≥ 50; playing internet games ≥20 h/week for ≥1 year Exclusion Criteria: current or history of psychiatric or neurological illness; current or history of use of illegal substances and other addictions; current use of psychotropic medications ; any history of head trauma, presence of metal in the body or other contraindication to functional MRI scanning

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 28 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Light therapy<br>about 30 individuals with internet gaming disorder will be randomly assigned to the light therapy group | Other: Light therapy<br>* The light therapy will be administered by custom-made light boxes (LED) with adjustable brightness. The light intensity will be set at 5000 Lux. The intervention will consist of daily exposure for 30 minutes in the morning. The whole intervention includes 14±5 days.<br>|
| Placebo Comparator: Light placebo<br>about 30 individuals with internet gaming disorder will be randomly assigned to the light placebo group | Other: Light placebo therapy<br>* The light placebo intervention will be administered by custom-made light boxes (LED) with adjustable brightness. The light intensity will be set at less than 200 Lux. The intervention will consist of daily exposure for 30 minutes in the morning. The whole intervention includes 14±5 days.<br>|
| Other: EABM training group<br>about 30 individuals with internet gaming disorder will be randomly assigned to the EABM training group | Other: Emotion Bias Modification Training<br>* The training aims at associating gaming pictures with negative words and pictures of healthy activities with positive words. Gaming pictures are always presented with a pair of negative words. Pictures of healthy activities are always presented with a pair of positive words. Each picture is presented with a fixed pair of words. Participants will be instructed to select one word to get the most monetary reward. Specifically, in response to each gaming picture, selecting one word will have a 70% chance to get a monetary reward and the other word will have a 30% chance to get a monetary reward. A similar rationale applies to the pictures of healthy activities. The reward setting will help consolidate target associations.Each training session includes 300 times/trials of each type of association, presented in pseudorandom way. The whole training includes 14±5 days. Participants will receive one training session every day.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| changes in gaming-related compulsive thoughts | The scores of gaming-related compulsive thoughts will be assessed with the Yale-Brown Obsessive-Compulsive Scale modified for internet gaming disorder. | baseline and within 1 day after intervention | 
| changes in gaming-related compulsive behaviors | The scores of gaming-related compulsive behaviors will be assessed with the Yale-Brown Obsessive-Compulsive Scale modified for internet gaming disorder. | baseline and within 1 day after intervention | 
| changes in IGD severity | The scores of IGD severity will be assessed with the internet addiction test for internet gaming disorder. | baseline , within one day after intervention, and one month after intervention | 
| changes in withdrawal symptoms | The scores of withdrawal symptoms will be assessed with the mood and physical symptoms scale. | baseline and within 1 day after intervention | 
| changes in weekly gaming time | weekly gaming time will be recorded by Software. | baseline and within 1 day after intervention | 
| changes in craving | Craving will be assessed using a Visual Analog Scale during a cue-reactivity task. | baseline and within 1 day after intervention | 
| changes in inhibition | Go NoGo task | baseline and within 1 day after intervention | 
| change of BOLD signals | Task-based fMRI and resting state fMRI. | baseline and within 1 day after intervention | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| changes in risk-taking tendencies | The balloon analogue risk task (BART) | baseline and within 1 day after intervention | 
| changes in the quality and patterns of sleep | The scores of the quality and patterns of sleep will be assessed with the Pittsburgh Sleep Quality Index (PSQI). | baseline and within 1 day after intervention | 
| changes in the severity of depression | The scores of the severity of depression will be assessed with the Beck Depression Inventory（BDI） | baseline and within 1 day after intervention | 
| changes in the severity of anxiety | The scores of the severity of anxiety will be assessed with the Beck Anxiety Inventory (BAI) | baseline and within 1 day after intervention | 
| changes in the severity of two emotion regulation strategies, cognitive reappraisal and expressive suppression | The scores of emotion regulation strategies will be assessed with the Emotion Regulation Questionnaire (ERQ) | baseline and within 1 day after intervention |