When we try to cope with stressful or challenging situations, our ability to regulate our responses towards these events is crucial. The general aim of this thesis was to investigate the role of prefrontal control over approach-avoidance tendencies in explaining individual differences in stress vulnerability and emotional responsivity. The large NWO-subsidized prospective longitudinal Police-In-Action (PIA) study enabled me to address this question in early-career police officers at high risk for trauma-exposure.

Imagine you are the survivor of a horrible car crash. One day, while you’re walking down the street, you hear a car horn followed by a screeching noise. Before you get a chance to look around and figure out what happened, you feel a sudden rush of adrenaline. Fear paralyzes you from head to toe, and your mind fills up with images of the accident in which you were involved not long ago. It may look like you’re overreacting from the outside, but from the inside, everything feels so ‘real’ and overwhelming. And so, you sit there shaking and waiting for something horrible to happen.

Post-traumatic stress disorder is a common condition that affects millions of people across the world. Up to date recommendations based on the best available evidence are vital to prevent and treat this debilitating condition. In this issue, we are bringing together a series of systematic reviews and meta-analyses that underpinned the development of the 2018 International Society for Traumatic Stress Studies Guidelines.

Background: Treatments for posttraumatic stress (PTS) are effective for many but not all people. There is a continued need to further our understanding of psychological mechanisms involved in the development and maintenance of PTS. Research has examined dysregulation of negative affect (NA) in PTS but relatively little attention has been paid to the role of dysregulation of positive affect (PA) in PTS.