Stress can have profound effects on health, emotion and cognition. For example, stress promotes a shift from goal-directed to habitual control of behaviour, which has been related to an increased risk of relapsing to addictive behaviours following stressful experiences. Why are some people particularly sensitive to the effects of stress, and thus more susceptible to stress-induced relapses to maladaptive, addictive behaviour? In the proposed project, I will systematically address the underlying architecture and the sources of interindividual differences in the vulnerability to the stress-induced shift towards habits by focussing on the assumed link between these shifts and the mineralocorticoid receptors (MR). Specifically, I will (i) examine rapid versus delayed stress effects and the underlying neural signature using EEG, and (ii) employ a behavioural genetics approach to examine naturally occurring genetic variants. The proposed project will be performed in the lab of Prof. Lars Schwabe, a world-leading expert on stress and cognition, at the University of Hamburg, Germany. This project will provide novel insights into the mechanisms underlying habit behaviour after stress and interindividual difference. Thereby, shedding light on the role of stress in relapsing to addictive behaviour, this can then be utilized in better treatment and prevention of addiction.