The ability to control our automatic action tendencies is essential for almost every human interaction. However, control over our automatic tendencies is often compromised in challenging in situations when people fall back on automatic ‘freeze-fight-flight’ (FFF) responses. Stress-induced lack of control over FFF-tendencies constitutes a problem endemic to high-risk professions (e.g. the police) leading to poor performance and increased risk for posttraumatic stress disorder (PTSD). Subsyndromal PTSD-symptoms are prevalent among police officers and automatic FFF-behaviors are suggested to form the major maintaining factor. However, most research has predominantly focused on the cognitive aspects of this disorder and has largely neglected automatic FFF-behaviors.
This prospective longitudinal NWO-VICI funded project encompasses a close collaboration between the Radboud University Nijmegen and the National Police Academy. We test resilience factors that protect against the adverse effects of trauma exposure on the development of stress symptoms in Dutch police recruits. The study consisted of two waves of data assessment (Figure 1). The first assessment wave (wave 1; pre-exposure) took place before police recruits made the transition from the relatively safe environment of theoretical training to their first services in the emergency aid. The second assessment wave (wave 2; post-exposure) took place after the police recruits had been exposed to the relative stressful services in the emergency aid. With these data we have been able to prospectively predict trauma-related changes in phenotypic PTSD symptoms, on the basis of pre-existing markers (i.e. behavioral, psychophysiological and neural measures) assessed at wave 1.
Police-in-Action team: Mahur Hashemi, Reinoud Kaldewaij, Wei Zhang, Tiele Döpp, Naomi de Valk, Madine Zoet, Job de Brouwer, Floris Klumpers, Saskia Koch & Karin Roelofs
Funding: NWO-VICI (Roelofs)
Figure legend: FC=fear conditioning, PRL = probabilistic reversal learning, PTSD=posttraumatic stress disorder, CAPS = clinician-administered PTSD scale, RS=resting-state, SECPT=socially evaluated cold pressure task.
Selected publications
De Voogd L, Hashemi M, Zhang W, Kaldewaij R, Koch S, van Ast V, Klumpers F, Roelofs K (2025). Amygdala hyperactivity in PTSD: disentangling predisposing from consequential factors in a prospective longitudinal design. Biological Psychiatry. S0006-3223(25)00993. doi: 10.1016/j.biopsych.2025.02.894.
Kaldewaij R, Koch SBJ, Hashemi MM, Zhang W, Klumpers F, Roelofs K. (2021) Anterior prefrontal brain activity during emotion control predicts resilience to post-traumatic stress symptoms. Nature Human Behaviour. 5, 1055–1064.
Zhang W, Kaldewaij R, Hashemi M, Koch S, Smit A, van Ast V, Beckmann C, Klumpers F, Roelofs K. (2022). Acute-stress induced change in salience network coupling prospectively predicts post-trauma symptom-development. Translational Psychiatry 12:63 https://www.nature.com/articles/s41398-022-01798-0.pdf?origin=ppub
Koch SBJ, Morey RA, Roelofs K. (2020). The role of the dentate gyrus in stress-related disorders. Molecular Psychiatry. 25(7):1361-1363.