PET imaging reveals brain functional changes in internet gaming disorder.

Area of Science:

• Neuroscience
• Psychiatry
• Radiology

Background:

• Internet gaming disorder (IGD) poses a growing global challenge, causing significant academic, social, and occupational impairment.
• The underlying neurobiological mechanisms of IGD remain poorly understood.
• This study investigates brain dopamine D2 (D2) and Serotonin 2A (5-HT2A) receptor function and glucose metabolism in individuals with IGD.

Purpose of the Study:

• To assess brain D2/5-HT2A receptor function and glucose metabolism in the same subjects using positron emission tomography (PET).
• To explore the correlation between D2 receptor availability and brain glucose metabolism in IGD.
• To elucidate the neurobiological underpinnings of compulsive behavior in IGD.

Main Methods:

• PET imaging was used with (11)C-N-methylspiperone ((11)C-NMSP) to measure D2/5-HT2A receptor availability.
• PET imaging with (18)F-fluoro-D-glucose ((18)F-FDG) was employed to assess regional brain glucose metabolism.
• Imaging data were acquired from 12 drug-naive adult males with IGD and 14 matched controls under resting and gaming task conditions.

Main Results:

• Individuals with IGD exhibited significantly reduced glucose metabolism in the prefrontal, temporal, and limbic systems.
• D2 receptor dysregulation was observed in the striatum of IGD subjects, correlating with years of overuse.
• Lower striatal D2 receptor levels were significantly associated with decreased glucose metabolism in the orbitofrontal cortex.

Conclusions:

• This study provides the first evidence linking D2 receptor levels with glucose metabolism in individuals with IGD.
• D2/5-HT2A receptor-mediated dysregulation in the orbitofrontal cortex may contribute to the loss of control and compulsive behaviors characteristic of IGD.
• Understanding these neurobiological mechanisms is crucial for developing targeted interventions for internet gaming disorder.