Alterations in gray matter microstructure and functional connectivity after acute stress.

Area of Science:

• Neuroscience
• Neuroimaging
• Trauma Research

Background:

• Trauma exposure is linked to gray matter (GM) changes, but acute stress effects are unclear.
• Understanding neurobiological abnormalities after acute stress is crucial for intervention.

Purpose of the Study:

• Investigate structural and functional brain changes in acute stress (motor vehicle accident survivors).
• Assess sex differences in GM microstructure and functional connectivity.
• Explore associations between GM structure and anxiety symptoms.

Main Methods:

• Compared 32 MVA survivors and 31 controls using MRI (MD, FA, GMV).
• Examined medial orbitofrontal cortex (mOFC), amygdala, hippocampus, insula, and anterior cingulate cortex (ACC).
• Conducted functional connectivity (FC) and correlation analyses.

Main Results:

• MVA survivors showed lower fractional anisotropy (FA) in mOFC and ACC.
• Females in the MVA group had lower mean diffusivity (MD) in the right ACC.
• Reduced connectivity between right mOFC and left inferior OFC was observed in MVA survivors.

Conclusions:

• Motor vehicle accident survivors exhibit GM microstructure alterations soon after trauma.
• These changes may lead to functional consequences in brain networks.
• Findings support timely interventions for acute stress.