Description

So far, no study examined selective oxytocin (OXT) effects on reactive (midbrain periaqueductal gray (PAG), central amygdala (CeA), hypothalamus, and the midcingulate cortex (MCC)) and cognitive fear (ventromedial prefrontal cortex (vmPFC), posterior cingulate cortex (PCC), hippocampus, and basolateral amygdala) and the reward system (striatum) with high spatial resolution. Previous studies showed that 7T functional magnetic resonance imaging (fMRI) results in a higher spatial resolution and specificity than 3T MRI in these brain regions and would thus allow for a more detailed characterization of the neural effects.

To disentangle (sub)region-specific effects of OXT on task-related activations of the cingulate structures, the amygdala, the striatum, PAG and VMPFC, the investigators plan to acquire ultra-high field 7T fMRI data from healthy male participants while they perform (i) an emotional face matching task and (ii) a flight initiation distance (FID) task involving fast- or slow-attacking virtual predators that elicit distinct activations in the reactive and cognitive fear circuits. Furthermore, participants will be pre-stratified depending on RAGE polymorphisms to elucidate possible RAGE-related differential OXT effects.