Table 2.
Task related functional magnetic resonance imaging studies on internet addiction disorder
| Ref. | Design and aims | Participants | Diagnostic criteria and evaluation scales | Task and behavioral results | fMRI methods | fMRI results |
| Ko et al[17] | Task related fMRI study | n = 20; Males 100% | DCIA-C | Task used: Cue-reactivity paradigm. | Scanner: 3 T | Between group significant effects: IGD > NC in: R OFC, R basal ganglia (caudatum and accumbens), bilateral ACC, bilateral MFG, R DLPFC |
| Aim: To identify the neural substrates of IGD by means of a cue-reactivity paradigm | Medication free 100% | MINI | Task design: Videogame viewing | fMRI scan duration: 4.8 min | ||
| Right-handed 100% | CIAS | Behavioral results: Gaming craving: IGD > NC | Acquisition method: Block design | |||
| Normal neurological examination 100% | Software used: SPM2 | |||||
| No comorbid psychiatric disorders or substance use | AUDIT | Signal analyzed: BOLD | ||||
| Groups: | FTND | Whole brain and ROI based analysis | ||||
| IGD n = 10 | Gaming craving scale | |||||
| Mean age: 22 ± 1.5 yr | For IGD: Addiction to World of Warcraft | |||||
| NC n = 10 | Playing > 30 h/wk | |||||
| Mean age: 22.7 ± 1.3 yr | ||||||
| Han et al[19] | Six-week open label pharmacological study with task related fMRI acquisition | n = 19; Males 100% | SCID | Task used: Cue-reactivity paradigm. | Scanner: 1.5 T | Between group significant effects: |
| Aim: To evaluate the efficacy of bupropion SR in reducing game craving and influencing brain activity in IGD | Medication free (at study enter) 100% | BDI < 17 | Task design: Videogame viewing | fMRI scan duration: 7.5 min | At baseline: | |
| Normal neurological examination 100% | 7 point Gaming Craving VAS | Behavioral results: Gaming craving: IGD > NC | Acquisition method: Block design | (1) IGD > NC in: L occipital lobe, cuneus, L DLPFC, L PH | ||
| No comorbid psychiatric disorders or substance use disorders | For IGD: YIAT > 50 | Bupropion effects in the IGD group: Significant decreases of: Craving (23.6%, P = 0.04) | Software used: Brain voyager | After 6 wk of Bupropion treatment on IGD: | ||
| Groups: IGD n = 11 | Playing > 4 h/d and 30 h/wk | Playing game time (35.4%, P = 0.01) | Signal analyzed: BOLD | (2) Significant decreased activation in L DLPFC | ||
| Mean age: 21.5 ± 5.6 yr | Addiction to star craft | YIAT scores (15.4%, P = 0.01) | Acquisition time: | |||
| Study treatment: Bupropion SR for 6 wk | (1) At study enter (baseline); | |||||
| NC n = 8 | (2) After 6 wk of Bupropion treatment | |||||
| Mean age: 20.3 ± 4.1 yr | Whole brain analysis | |||||
| Dong et al[20] | Task related fMRI study | n = 27; Males 100% | MINI | Task used: Guessing task | Scanner: 3 T | Between group significant effects: |
| Aim: To investigate reward and punishment processing in IGD during a guessing task | Medication free 100% | For IGD: YIAT > 80 | Task design: Two-choices gain or loss guessing task | fMRI scan duration: 16.3 min | In WIN condition: IGD > NC in L OFC (BA 11) | |
| Right-handed 100% | C-IAT criteria | Behavioral results: No between group significant differences in accuracy and reaction times | Acquisition method: Block design | In LOSS condition: NC > IGD in ACC | ||
| Normal neurological examination 100% | Spending most of their time playing online Internet games | Software used: SPM5 | ||||
| No comorbid psychiatric disorders or substance use disorders | For NC: YIAT < 20 | Signal analyzed: BOLD | ||||
| Groups: IGD n = 14 | Whole brain analysis | |||||
| Mean age: 23.4 ± 3.3 yr | ||||||
| NC n = 13 | ||||||
| Mean age: 24.1 ± 3.2 yr | ||||||
| Dong et al[22] | Task related fMRI study | n = 24; Males 100% | For all participants: BDI < 13 | Task used: Cognitive control task | Scanner: 3 T | Between group significant effects: |
| Aim: To identify the neural correlates of response inhibition in individuals with and without IGD | Medication free 100% | For IGD: YIAT > 80 | Task design: Three-choices color-word Stroop task | fMRI scan duration: 12 min | During Stroop effect: IGD > HC in: ACC, PCC, L insula, MiFG, MFG, L thalamus, R IFG, R SFG | |
| Right-handed 100% | C-IAT criteria | Behavioral results: No between group significant differences | Acquisition method: Event-related design | |||
| No comorbid psychiatric disorders or substance use disorders | Spending most of their time playing online Internet games | Software used: SPM5 | ||||
| Non smokers 100% | YIAT < 20 | Signal analyzed: BOLD | ||||
| Groups: IGD n = 12 | Whole brain analysis | |||||
| Mean age: 23.6 ± 3.5 yr | ||||||
| NC n = 12 | ||||||
| Mean age: 24.2 ± 3.1 yr | ||||||
| Lorenz et al[23] | Task related fMRI study | n = 17; Males 100% | World of warcraft addiction inventory | Task used: Attentional bias/cue reactivity task | Scanner: 3 T | Between group significant effects |
| Aim: To assess neural correlates of attentional bias and cue reactivity in IGD | Groups: IGD n = 8 | CSVK | Task design: Two-choice dot probe paradigm during SP and LP trials | fMRI scan duration: 30 min | During SP trials | |
| Mean age: 25 ± 7.4 yr | Vocabulary test (WST-IQ) | Stimulus class: | Acquisition method: Block design | IGD > NC in bilateral ACC, R MPFC, L OFC, L PH, MTG, precuneus, cerebellum, R amygdala | ||
| NC n = 9 | Test of attention | (1) IAPS based emotional images (neutral and positive valences) | Software used: SPM8b | During LP trials IGD > NC in: R IFG, R Hippocampus, bilateral lingual gyrus and R calcarine gyrus | ||
| Mean age: 24.8 ± 6.9 yr | Social interaction anxiety scale | (2) Computer generated stimuli (neutral images and World of Warcraft based images) | Signal analyzed: BOLD | PPI results: IGD > NC in connectivity between R IFG and: | ||
| STAI | Behavioral results: | Whole brain analysis | IFG, orbital gyrus, MFG, MTG, MOG, STG, ITG, Angular gyrus, precuneus, basal ganglia | |||
| BDI | In SP trials: IGD: RT congruent < RT incongruent | Connectivity analysis: Post hoc PPI, using R IFG as seed region | ||||
| BIS 11 | ||||||
| Iowa Gambling test | ||||||
| For IGD: ≥ 3 Grüsser and Thalemann’s criteria for computer game addiction | ||||||
| Dong et al[24] | Task related fMRI study | n = 30; Males 100% | MINI | Task used: Cognitive control task | Scanner: 3 T | Between group significant effects |
| Aim: To investigate error-monitoring ability in IGD | Medication free 100% | For IGD | Task design: Three-choices color-word Stroop task | fMRI scan duration: 12 min | During correct responses: | |
| Right-handed 100% | YIAT > 80 | Focus: Error monitoring | Acquisition method: Event-related design | IGD < NC in OFC and ACC | ||
| Non smokers 100% | Spending > 80% of their time online playing games | Behavioral results: No significant between | Software used: SPM8 | During incorrect responses: IGD > NC in ACC | ||
| No comorbid psychiatric disorders or substance use disorders | For NC: YIAT < 30 | group effects | Signal analyzed: BOLD | |||
| Groups: IGD n = 15 | Whole brain analysis | |||||
| Mean age: 23.8 ± 3.7 yr | ||||||
| NC n = 15 | ||||||
| Mean age: 24.1 ± 3.3 yr | ||||||
| Dong et al[25] | Task related fMRI study | n = 31; Males 100% | MINI | Task used: Guessing task | Scanner: 3 T | Between group significant effects |
| Aim: To investigate brain correlates of decision-making in IAD | Medication free 100% | BDI < 5 | Task design: Two-choices gain or loss guessing task | fMRI scan duration: 21 min | In WIN condition: IAD > NC in: ACC, insula and IFG | |
| Right-handed 100% | For IAD: YIAT > 80 | Behavioral results: | Acquisition method: Block design | IAD < NC in: PCC and caudatum | ||
| No comorbid psychiatric disorders or substance use disorders | For NC: YIAT < 30 | In LOSS condition: RT | Software used: SPM5 | In LOSS condition: IAD > NC in: Inferior CG | ||
| Groups: IAD n = 16 | IAD > NC | Signal analyzed: BOLD | IAD < NC in: PCC | |||
| Mean age 21.4 ± 3.1 yr | Whole brain analysis | |||||
| NC n = 15 | ||||||
| Mean age: 22.1 ± 3.6 yr | ||||||
| Dong et al[26] | Task related fMRI study | n = 31; Males 100% | MINI | Task used: Guessing task | Scanner: 3 T | Between group significant effects |
| Aim: To investigate reward/punishment sensitivities in IGD during a guessing task | Medication free 100% | BDI < 5 | Task design: Two-choices gain or loss guessing task | fMRI scan duration: 21 min | In WIN condition: IGD > NC in L SFG | |
| Right-handed 100% | For IGD: YIAT > 80 | No behavioral response was required | Acquisition method: Block design | In LOSS condition: IGD > NC in L SFG | ||
| No comorbid psychiatric disorders or substance use disorders | Spending > 80% of their time online playing games | Post scanning self-report questionnaire | Software used: SPM5 | IGD < NC in bilateral PCC | ||
| Groups: IGD n = 16 | For NC: YIAT < 30 | (1) On subjective experiences | Signal analyzed: BOLD | In WIN-LOSS contrast condition | ||
| Mean age 21.4 ± 3.1 yr | During LOSS condition: | Whole brain analysis | IGD > NC in L SFG | |||
| NC n = 15 | IGD < NC in reporting negative emotions | |||||
| Mean age: 22.1 ± 3.6 yr | (2) On craving for win: | |||||
| IGD > NC in both WIN and LOSS conditions | ||||||
| Dong et al[27] | Task related fMRI study | n = 30; Males 100% | MINI | Task used: Cognitive control task | Scanner: 3 T | Between group significant effects |
| Aim: To explore cognitive flexibility in IGD during a color-word Stroop task | Medication free 100% | BDI < 5 | Task design: Three-choices color-word Stroop task | fMRI scan duration: 16 min | Task switching | |
| Right-handed 100% | For IGD: YIAT > 80 | Focus: Cognitive flexibility during task switching (from easy to difficult condition and viceversa) | Acquisition method: Event-related design | (1) From difficult to easy condition | ||
| No comorbid psychiatric disorders or substance use disorders | Spending > 80% of their time online playing games | Behavioral results: No significant between group differences | Software used: SPM5 | IGD > NC in: Bilateral insula, R STG | ||
| Groups: IGD n = 15 | For NC: YIAT < 30 | Signal analyzed: BOLD | (2) From easy to difficult condition: IGD > NC in: Bilateral precuneus, L STG, L angular gyrus | |||
| Mean age 21.2 ± 3.2 yr | Whole brain analysis | |||||
| NC n = 15 | ||||||
| Mean age: 22.1 ± 3.6 yr | ||||||
| Ko et al[28] | Task related fMRI study | n = 49; Males 100% | MINI | Task used: Cognitive control task | Scanner: 3 T | Between group significant effects |
| Aim: To evaluate impulsivity and brain correlates of response inhibition and error processing in IGD | Medication free 100% | CIAS | Task design: Go/No-go Task | fMRI scan duration: 15.5 min | During response inhibition | |
| Right-handed 100% | BIS-11 | Behavioral results: No significant between group differences | Acquisition method: event-related design | IGD > NC in bilateral caudate and L OFG (BA 47) | ||
| No comorbid psychiatric disorders or substance use disorders | Dickman’s impulsivity scale | Software used: SPM5 | During error processing | |||
| Groups: IGD n = 26 | For IGD: Fulfilling DCIA criteria | Signal analyzed: BOLD | IGD < NC in R insula | |||
| Mean age 24.6 ± 3.2 | Addiction to online gaming | Whole brain and ROI based analysis | ||||
| NC n = 23 | ||||||
| Mean age: 24.4 ± 2.1 yr | ||||||
| Liu et al[29] | Task related fMRI study | n = 22; Males 100% | DCIA-C | Task used: Cognitive control task | Scanner: 3 T | Between group significant effects |
| Aim: To investigate brain correlates of response inhibition under gaming cue distraction in IGD | Medication free 100% | MINI | Task design: Modified Go/no-go Task with gaming cue distracters | fMRI scan duration: 8.5 min | During no gaming distracting condition | |
| Right-handed 100% | CIAS | Behavioral results: During gaming distracting condition | Acquisition method: Block design | IGD > NC in R SPL | ||
| No comorbid psychiatric disorders or substance use disorders | FTND < 5 | Commission errors IGD > NC | Software used: SPM5 | During gaming distracting condition | ||
| Groups: IGD n = 11 | Signal analyzed: BOLD | NC > IGD in R DLPFC, R SPL and cerebellum | ||||
| Mean age 23.4 ± 2.3 yr | Whole brain and ROI based analysis | ROI based analysis results | ||||
| NC n = 11 | In IGD | |||||
| Mean age: 22.4 ± 1.7 yr | R DLPFC and R SPL activations were positively associated to commission errors during gaming distracting condition | |||||
| Chen et al[30] | Task related fMRI study | n = 30; Males 100% | MINI | Task used: Cognitive control task | Scanner: 3 T | Between group significant effects |
| Aim: To evaluate neural correlates of response inhibition among subjects with IGD | Medication free 100% | CIAS | Task design: Go/no-go Task | fMRI scan duration: 6 min | During response inhibition | |
| Right-handed 100% | Behavioral results: No significant between group differences | Acquisition method: Block design | NC > IGD in R SMA/pre-SMA | |||
| No comorbid psychiatric disorders or substance use disorders | BIS-11 | Software used: SPM5 | ||||
| Groups: IGD n = 15 | For IGD: Fulfilling DCIA criteria | Signal analyzed: BOLD | ||||
| Mean age 24.7 ± 3.1 yr | Addiction to World of Warcraft | ROI based analysis | ||||
| NC n = 15 | ||||||
| Mean age: 24.5 ± 2.8 yr | ||||||
| 1Dong et al[31] | Resting-state and task related fMRI | All participants: n = 71 age 22.35 | IGD: YIAT ≥ 50 | Task used: Cognitive control task | Scanner: 3 T | Between group significant effects |
| Aim: To examine the Fc of ECN during both resting state and Stroop task performing | Participants who performed the fMRI Stroop task: n = 35 | > 80% of the online time was spent playing videogames | Task design: Three-choices color-word Stroop task | fMRI scan duration: 15 min | During incongruent trials: IGD > NC in bilateral SFG | |
| Males 100% | BDI < 5 | Behavioral results: No significant between group differences | Acquisition method: Event-related design | IGD < NC in L | ||
| Medication free 100% | MINI: No Axis I psychiatric disorders | Software used: SPM8 | DLPFC, ACC and left OFC | |||
| Right-handed 100% | IAD | Signal analyzed: BOLD | ||||
| No DSM 5 psychiatric disorders | Whole brain and ROI based analysis | |||||
| Groups performing fMRI Stroop task: | ||||||
| IGD n = 16 | ||||||
| NC n = 15 | ||||||
| Liu et al[33] | Task related fMRI study | n = 38; Males 58% | HAM-A | Task used: Cue-reactivity paradigm. | Scanner: 3 T | Between group significant effects |
| Aim: To investigate brain function in IGD individuals during a cue-reactivity paradigm | Medication free 100% | BDI | Task design: Videogame viewing | fMRI scan duration: 7.5 min | IGD > NC in: R SPL, R precuneus, R insula, R CG, R STG, L brain stem | |
| Right-handed 100% | For IGD: Beard's DQIA "5 + 1 criteria" plus any one of: ≥ 6 h/d for 3 mo; Decline in academic performance; Unable to maintain normal school learning | No behavioral response was required | Acquisition method: Block design | |||
| No comorbid psychiatric disorders or substance use disorders | Software used: Brain Voyager | |||||
| Groups: IGD n = 19 | Signal analyzed: BOLD | |||||
| Males n = 11 (58%) | Whole brain analysis | |||||
| Mean age 21.4 ± 1.0 yr | ||||||
| NC n = 19 | ||||||
| Mean age: 20.1 ± 1.1 yr | ||||||
| Males n = 11 (58%) |
1
Only task related fMRI results are showed. IAD: Internet addiction disorder; IGD: Internet gaming disorder; NC: Normal controls; AUDIT: Alcohol use disorder identification test; BDI: Beck depression inventory; BIS-11: Barratt impulsiveness scale-version 11; CIAS: Chen internet addiction scale; C-IAT: Chinese internet addiction test; CSVK: Pathological computer gaming scale; DCIA-C: Diagnostic criteria of Internet addiction for college students; FTND: Fagerstrom test for nicotine dependence; HAM-A: Hamilton anxiety scale; IAPS: International affective picture system; MINI: Mini international neuropsychiatric interview; RT: reaction times; SCID: Structured clinical interview for DSM-IV; VAS: Visual analogue scale; YIAT: Young’s internet addiction test; R: Right; L: Left; ACC: Anterior cingulate cortex; CG: Cingulate gyrus; DLPFC: Dorsolateral prefrontal cortex; IFG: Inferior frontal gyrus; IPL: Inferior parietal lobule; ITG: Inferior temporal gyrus; MFG: Medial frontal gyrus; MPFC: Medial prefrontal cortex; MiFG: Middle frontal gyrus; MOG: Middle occipital gyrus; MTG: Middle temporal gyrus; OFC: Orbitofrontal cortex; PCC: Posterior cingulate cortex; PH: Parahippocampus; SMA: Supplementary motor area; SFG: Superior frontal gyrus; SPM: Statistical parametric mapping; SPL: Superior parietal lobe; STG: Superior temporal gyrus; SP: Short presentation; LP: Long presentation.