Project title: Behavioural and brain network adaptations associated with chronic amygdala hyperactivation

Highlights: This 3-years funding will allow the investigation of the brain network adaptations resulting from chronic stress and hyperactivation of the amygdala and their contribution to the expression of depressive-like behavior.

Synopsis: This study focuses on identifying the behavioural and brain network adaptations associated with chronic hyperactivity of the amygdala, a key brain involved in emotion regulation, anxiety and depression. While a lot is known about amygdala activity and its roles, the effects of sustained amygdala hyperactivity are unclear. Using small animal brain imaging, we recently showed that chronic stress in mice increases amygdala structural connectivity at the detriment of overall brain structural synchrony. A similar shift was found in people with childhood trauma history. In this study we will determine: 1) if chronic stress-induced amygdala structural changes appear first and induce brain-wide changes, that maps onto specific behavioural dimensions, 2) if artificial chronic amygdala hyperactivation causes depressive-like behavioural and structural changes, 3) if hyperactivated amygdala can predict treatment resistance.