Brain connectivity aberrations in anabolic-androgenic steroid users

Area of Science:

• Neuroscience
• Endocrinology
• Psychiatry

Background:

• Sustained anabolic-androgenic steroid (AAS) use is associated with adverse behavioral outcomes like aggression and impulsivity.
• Potential mechanisms involve disruptions in brain networks rich in androgen receptors, crucial for emotional and cognitive control.

Purpose of the Study:

• To investigate the effects of AAS on resting-state functional brain connectivity in a large cohort of male AAS users.
• To correlate observed connectivity changes with AAS dependency, lifetime exposure, and cycle state.

Main Methods:

• Collected resting-state functional magnetic resonance imaging (fMRI) data from 151 males (50 current AAS users, 16 former users, 59 controls).
• Utilized Independent Component Analysis (ICA) and dual regression to estimate brain network nodes and time-series.
• Defined functional connectivity matrices via partial correlations between estimated network nodes.

Main Results:

• Current AAS users showed reduced functional connectivity between key emotional and cognitive regulation nodes.
• Specifically, decreased connectivity was observed between the amygdala and the default-mode network (DMN).
• Reduced connectivity was also found between the dorsal attention network (DAN) and a frontal node (SFG/IFG/ACC), correlating with dependency and usage intensity.

Conclusions:

• Anabolic-androgenic steroid use is linked to significant alterations in resting-state functional brain connectivity.
• These disruptions, particularly in emotion and attention networks, may underlie the observed behavioral consequences of AAS use.
• Connectivity changes are modulated by the extent of AAS dependency, lifetime exposure, and current usage status (on/off cycle).