Mapping Stress and Pain Interactions (G072323N)

The over-arching goal of this observational (case-control, with a cross-sectional and longitudinal arm) study is to comprehensively map stress system (dys)function (including reactivity and recovery) in people with primary musculoskeletal (MSK) pain and a pain-free control group. * The primary objective is to characterize stress systems functioning and their relation to pain in individuals with subacute versus chronic, and localized versus widespread MSK pain, and compare to pain-free controls. * The secondary objective is to define the contribution of stress system functioning to trajectories of MSK pain, including pain chronification or recovery from pain. Researchers will compare primary musculoskeletal pain groups with pain-free controls. Participants will: * Fill out online questionnaires. * Provide a sample of hair and saliva to assess chronic and acute stress hormone levels, respectively. Saliva samples will be collected both in the lab and at home. * Be subject to psychophysiological monitoring. * Partake in quantitative sensory testing measuring pain thresholds, tolerances and pain modulation of pressure and heat. These tests will be repeated twice: before and after an acute-stress induction task. * Partake in a series of stress-inducting tasks. * Be subject to MRI-scans of the brain, including structural and functional MR acquisitions (e.g., during rest and during pain inductions). Participants will be invited for a second session of the same assessments six months later to observe possible connection between pain trajectory and stress system (dys)function.