Perceived Stress, Cortical GABA, and Functional Connectivity Correlates: A Hypothesis-Generating Preliminary Study.

Area of Science:

• Neuroscience
• Psychiatry
• Neuroimaging

Background:

• Stress and its dysregulation are linked to mood, anxiety, and cognitive disorders.
• Perceived stress, an individual's appraisal of stress and coping ability, affects resting-state brain networks.
• GABAergic system alterations may underlie stress-related network dysfunction, but this link is unexplored.

Purpose of the Study:

• To investigate the association between perceived stress (using the Perceived Stress Scale - PSS) and prefrontal GABA levels.
• To examine the relationship between perceived stress and resting-state functional connectivity (RSFC).

Main Methods:

• Magnetic Resonance (MR) spectroscopy measured GABA levels in the anterior cingulate cortex (ACC), left dorsolateral prefrontal cortex (DLPFC), and ventromedial prefrontal cortex (VMPFC).
• Resting-state functional scans (3 Tesla) assessed RSFC within and between the default mode (DMN), salience (SN), and central executive networks (CEN), hippocampus, and amygdala.

Main Results:

• A significant negative correlation was found between total PSS scores and left DLPFC GABA levels (r = -0.62, p = 0.023).
• No significant correlations were observed between PSS scores and RSFC measures (all p > 0.148).

Conclusions:

• Preliminary findings suggest a link between perceived stress and GABAergic function in the DLPFC, a critical component of the CEN.
• These results support the role of the CEN in perceived stress and may guide treatments for stress-related conditions.