The dynamics of the stress neuromatrix

Stressful stimuli in healthy subjects trigger activation of a consistent and reproducible set of brain regions; yet, the notion that there is a single and constant stress neuromatrix is not sustainable. Indeed, after chronic stress exposure there is activation of many brain regions outside that network. This suggests that there is a distinction between the acute and the chronic stress neuromatrix. Herein, a new working model is proposed to understand the shift between these networks. The understanding of the factors that modulate these networks and their interplay will allow for a more comprehensive and holistic perspective of how the brain shifts 'back and forth' from a healthy to a stressed pattern and, ultimately, how the latter can be a trigger for several neurological and psychiatric conditions.FCT and COMPETE through the projects EXPL/NEU-OSD/2196/2013 and FCT-ANR/NEU-OSD/0258/2012 founded by FCT/MEC, by Fundação Gulbenkian through the project ‘PhenoTEMPO’ and by Fundo Europeu de Desenvolvimento Regional (FEDER) through ‘Programa Operacional Regional do Norte (ON.2–O Novo Norte), ao abrigo do Quadro de Referência Estratégico Nacional (QREN)’ and by the European Commission (FP7): ‘SwitchBox’ (Contract HEALTH-F2-2010-259772