Perceived stress modulates the activity between the amygdala and the cortex.

Area of Science:

• Neuroscience
• Psychiatry
• Functional Neuroimaging

Background:

• Stress significantly impacts brain function and is linked to psychiatric disorders.
• Previous research shows a correlation between perceived stress and amygdala volume in healthy individuals.
• The functional mechanisms underlying this association remain unclear.

Purpose of the Study:

• To investigate the functional connectivity alterations associated with perceived stress.
• To explore the relationship between perceived stress and dynamic brain connectivity patterns.
• To understand how perceived stress affects amygdala connectivity with other brain regions.

Main Methods:

• Utilized resting-state functional magnetic resonance imaging (fMRI) data from 252 healthy subjects.
• Performed seed-based amygdala connectivity analysis (static connectivity).
• Employed a whole-brain, data-driven approach to analyze dynamic connectivity and phase interactions.

Main Results:

• Increased perceived stress correlated with heightened amygdala connectivity to frontal cortical regions.
• This heightened connectivity was associated with a decreased occurrence of anti-correlated activity between the amygdala and hippocampus.
• Dynamic connectivity analysis revealed altered phase synchrony patterns.

Conclusions:

• Reinforces the detrimental impact of in-phase synchrony between subcortical and cortical brain areas under stress.
• Highlights the protective role of counterbalanced (phase-shifted) activity between brain subsystems.
• Suggests dynamic connectivity analysis offers insights missed by traditional correlation-based methods.