Oxytoxin, whether functioning as a hormone or a neurotransmitter, is involved in a series of important physiological and psychological functions. For example, it promotes maternal attachment, lactation, pair bonding and group cohesion. However, the picture is actually far more complex, just think that it can sometimes even lead to aggressive behaviour.
Experimental results also show that intranasal administration (with a spray) of oxytocin makes people more willing to take care of others and better at recognizing emotions.