Effects of Oxytocin on the Functional Architecture of the Brain Before and After Prolonged Naturalistic Fear Induction

Effects of Oxytocin on the Functional Architecture of the Brain Before and After Prolonged Naturalistic Fear Induction

The main aim of the pharmacological resting-state fMRI study is to investigate the modulatory effects of intranasal Oxytocin (24IU) on task and intrinsic functional connectivity before and after prolonged exposure to naturalistic fear induction via a movie.

In a double-blind placebo-controlled between-subject experimental design, 60 adult male subjects will be randomly allocated to either receive intranasal Oxytocin (24IU, n= 30) or intranasal placebo (nasal spray administration without oxytocin, n = 30). Following treatment administration subjects will undergo a resting state functional magnetic resonance imaging (fMRI) assessment (8min) and next watch a long fear-inducing (horror) movie (10min) followed by a resting state fMRI assessment (8min). Effects of treatment on subjective experience will be assessed using 1-9 Likert scales assessing subjective fear, emotional arousal and escape. Ratings will be acquired before the start of the experiment, after the movie and at the end of the experiment. Participants will undergo screening for psychopathological and emotional states before treatment. Together with a randomized assignment to the treatment groups, this will allow controlling for confounding between-group differences.

Inclusion Criteria:

• Healthy subjects without past or current psychiatric or neurological disorders
• Right-handedness
• Normal or corrected-normal version

Exclusion Criteria:

• History of head injury
• Medical or psychiatric illness
• Hypertension
• General cardio-vascular alteration or diseases
• Allergy against medications
• Visual or motor impairments
• Claustrophobia
• Drug addiction
• Nicotine dependence
• FMRI contradictions