Targeted Extinction of Drug Cues During Sleep - Olfactory Cue Reactivity Task

The intention of the study is to enhance the measurement precision in image-based cue reactivity task by introducing a new level of stimuli in the form of odours. During the course of the functional Magnetic Resonance Imaging (fMRI) screening, participants are required to finish three tasks, namely; odour-based cue reactivity task (OCRT), image-based cue reactivity task(ICRT) and monetary incentive delay task (MID). Participants will be randomly divided into two groups, one group will receive tasks in the following order: OCRT-MID-ICRT and the other group will receive them in the following order: ICRT-MID-OCRT. With this, the habituation effect from receiving odours during OCRT is expected to be balanced.