1. Introduction 1.1 Oxytocin (OT) OT is a nine-amino acid neuropeptide synthesized in the magnocellular neurons of the paraventricular (PVN) and supraoptic nuclei (SON) of the hypothalamus, and released by the pituitary gland (Meyer-Lindenberg, Domes, Kirsch, & Heinrichs, 2011). OT has both