Resting-State Functional Connectivity Does Not Predict Individual Differences in Perceived Psychological Stress Among...

It is theorized that appraisals of perceived psychological stress are represented in the brain. However, a neural signature that reliably predicts perceived stress has yet to be fully characterized. Accordingly, the present preregistered study tested whether whole-brain resting-state functional connectivity patterns predict individual differences in perceived stress.

Participants (N = 417; 53% female; 24.2% non-White; aged 30-54 years) completed the 10-item Perceived Stress Scale and underwent a 5-minute resting-state functional magnetic resonance imaging scan. Functional connectivity (FC) was computed between areas distributed across the brain. In total, 19,900 functional connections (edges) were retained for analyses. Cross-validated and multivariate machine learning methods were implemented. Using this approach, two penalized regression models with cross-validation-elastic net and ridge-were conducted to predict perceived stress from the edges.

Across the elastic net and ridge regression models, whole-brain resting-state FC patterns failed to predict individual differences in perceived stress. However, in exploratory analyses, they successfully generalized in cross-validation to predict age for both models (elastic net: r = 0.193, p < .0001, 95% CI = 0.099-0.284, RMSE = 6.661, MAE = 5.715, R2 = 0.037; ridge: r = 0.197, p < .0001, 95% CI = 0.103-0.287), RMSE = 6.613, MAE = 5.8140, R2 = 0.039).

These results suggest that resting-state FC patterns may not reliably predict individual differences in self-reported perceived stress among midlife adults.