OT was administered double-blind and placebo controlled in a between-subjects design. The participants self-administered 3 puffs in each nostril alternately of the unlabeled nasal spray. The amount of OT corresponded to 24 IU. The placebo spray consisted of chlorobutanol-hemihydrat (0.5%) with no active treatment. To ensure treatment efficiency57, exposure time was 45 min until the fMRI measurement began.