Linking brain structure to stress reactivity: cingulate surface area predicts acute cortisol responses

Area of Science:

• Neuroimaging
• Neuroendocrinology
• Psychophysiology

Background:

• Altered stress responses are linked to mental disorders.
• Brain structure's role in acute cortisol response to stress is underexplored in healthy individuals.
• Previous research focused on limited brain regions and functional measures.

Purpose of the Study:

• Investigate associations between brain structure and cortisol responses to psychosocial stress.
• Determine if hypothalamic-pituitary-adrenal axis reactivity can be predicted from brain morphology.
• Explore the predictive power of structural brain measures for stress-induced cortisol increases.

Main Methods:

• Included 291 healthy subjects (157 females, 18-62 years).
• Confirmatory analysis using Permutation Analysis of Linear Models (PALM) for associations between brain structure and cortisol.
• Exploratory whole-brain vertex-wise analysis and out-of-sample prediction of cortisol increases from structural measures.

Main Results:

• Smaller surface area in left and right anterior cingulate cortex (ACC) and posterior cingulate cortex associated with higher cortisol stress responses.
• Left ACC surface area was the most promising predictor in machine learning analyses.
• Associations were particularly noted in males, with other fronto-limbic structures also showing predictive value.

Conclusions:

• Cortical and subcortical structural measures, especially smaller ACC surface areas, predict acute hormonal stress responses.
• The left ACC emerged as a consistent and significant predictor of stress reactivity.
• Findings emphasize the role of specific brain structures in modulating the body's response to stress.