Emotional bonds can also form during periods of extreme duress, especially when the survival of one individual depends on the presence and support of another. There is also evidence that oxytocin is released in response to acutely stressful experiences, possibly serving as hormonal ‘insurance' against overwhelming stress. Oxytocin might help to assure that parents and others will engage with and care for infants, to stabilize loving relationships and to ensure that, in times of need, we will seek and receive support from others.
The case for a major role for oxytocin in love is strong, but until recently has been based largely on extrapolation from research on parental behaviour  or social behaviours in animals [5,6]. However, human experiments have shown that intranasal delivery of oxytocin can facilitate social behaviours, including eye contact and social cognition —behaviours that are at the heart of love.
Of course, oxytocin is not the molecular equivalent of love. It is just one important component of a complex neurochemical system that allows the body to adapt to highly emotive situations. The systems necessary for reciprocal social interactions involve extensive neural networks through the brain and autonomic nervous system that are dynamic and constantly changing during the lifespan of an individual. We also know that the properties of oxytocin are not predetermined or fixed. Oxytocin's cellular receptors are regulated by other hormones and epigenetic factors. These receptors change and adapt on the basis of life experiences. Both oxytocin and the experience of love change over time. In spite of limitations, new knowledge of the properties of oxytocin has proven useful in explaining several enigmatic features of love.