Fig. 1: Study design and effects of stress on salivary cortisol and subjective ratings.

a Schematic diagram of the study visits and approximate timing of MRS, fMRI RL task, VAMS, and saliva measurements. Note that the Healthy Control Stress sample did not complete resting-state scans, STRAIN, or EMA. EMA Ecological Momentary Assessment, MRS Magnetic Resonance Spectroscopy, PSS Perceived Stress Scale, RL Reinforcement Learning, RS Resting State, SCID Structured Clinical Interview for DSM Disorders, STRAIN Stress and Adversity Inventory. MAST Maastricht Acute Stress Test, VAMS Visual Analog Mood Scales. b Representative MRS voxel placement. c Representative MRS spectrum (black) and LCModel fit (red) with labeled metabolite peaks. arb.units arbitrary units, Cr creatine, PCr Phosphocreatine, Glu glutamate, Glx (glutamine + glutamate), GCP glycerophosphocholine and PC, phosphocholine (choline-containing metabolites), ml myo-inositol, MRS Magnetic Resonance Spectroscopy, NAA N-acetylaspartic acid, NAAG N-acetylaspartylglutamate, ppm parts per million. d Effect of MAST acute stress task and No Stress Control (NSC) on mood. Items are coded such that higher scores indicate greater negative emotional experience and averaged across items. Data represented as mean ± standard error of the mean (N = 75 participants). e Salivary cortisol response to acute stress manipulation and no-stress control. Graph depicts percent change in salivary cortisol from the timepoint immediately prior to the onset of the MAST stressor (Pre-MAST). Data represented as mean ± standard error of the mean (N = 83 participants). f Subjective stress ratings for each group (1–5). Data represented as mean ± standard error of the mean (N = 82 participants). HC Healthy Control participants, MDD participants with Major Depressive Disorder. Source data for d–f are provided as a Source Data file.