Global organization of functional brain connectivity in methamphetamine abusers

Area of Science:

• Neuroscience
• Systems Neuroscience
• Brain Connectivity

Background:

• Chronic methamphetamine abuse is a significant public health concern.
• Understanding its neurobiological underpinnings is crucial for developing effective interventions.
• Previous research suggests alterations in brain function, but global network organization remains less understood.

Purpose of the Study:

• To investigate the effects of chronic methamphetamine abuse on the global organization of functional brain connectivity.
• To compare brain network topology between methamphetamine abusers and healthy controls.

Main Methods:

• Eyes-closed resting-state electroencephalography (EEG) was recorded from 36 methamphetamine abusers and 36 healthy controls.
• EEG data were analyzed using visibility graph similarity and coherence methods to construct network matrices.
• Small-World Network properties (clustering coefficient, mean path length) were computed and statistically compared between groups.

Main Results:

• Methamphetamine abusers exhibited significantly higher clustering coefficients, lower mean path lengths, and higher C/L ratios in the gamma band compared to controls (p < 0.005).
• An artificial neural network classifier achieved 82.8% accuracy in distinguishing between methamphetamine abusers and healthy subjects based on these network properties.

Conclusions:

• Chronic methamphetamine abuse leads to a disrupted topology of functional brain networks.
• These disruptions are characterized by a deviation from Small-Worldness, particularly evident in the gamma frequency band.
• This quasi-experimental study provides novel insights into the neurobiological consequences of methamphetamine abuse on brain network organization.