Love is a physiological and physical phenomenon, as the architecture of your brain is altered forever by the love hormone, oxytocin.

Oxytocin is released by the brain with every touch, hug, or during the bonding of a mother and her newborn baby, but also of a father and his child. Now, a team at the University of California, San Diego (UCSD) School of Medicine is investigating how the "love hormone" could treat mental disorders, like schizophrenia and social anxiety.

"Oxytocin is a brain chemical associated with pair bonding, including mother-infant and male-female bonds, increased paternal involvement with children, and monogamy in certain rodents," Dr. Kai MacDonald, assistant clinical professor of psychiatry at UCSD, told ScienceDaily.com.

Oxytocin is crucial in human sexual reaction and being hugged or touched by the partner makes the brain release higher doses. This molecule seems to bias social recognition via facial expressions, maybe by affecting synapse formation in the amygdala, the main brain nucleus involved in processing emotions, impacting the subject's behavior.

"That's why oxytocin is sometimes called 'the love hormone. It's said that the eyes are the window to the soul…they certainly are the window to the emotional brain. We know that the eye-to-eye communication-which is affected by oxytocin-is critical to intimate emotional communication for all kind of emotions - love, fear, trust, anxiety. People with schizophrenia or autism often avoid eye-to-eye gaze, focus on less relevant areas of the face, and avoid meaningful social contact," said MacDonald.

Oxytocin treatment could boost trust or emotional contact in patients suffering of schizophrenia and anxiety. The hormone is already used under the trade name of Pitocin to trigger labor and increase lactation in women, but its neural action still requires a lot of research.

"Previously studies of healthy individuals have shown that intranasal doses of oxytocin reduce activation of brain circuits involved in fear, increase levels of eye contact, and increase both trust and generosity. Interestingly, people given oxytocin don't report feeling any different, but they act differently. A hug or a touch that causes a releases of this hormone might change brain signals. We want to know if oxytocin can also impact social and emotional behavior in patients with psychiatric disorders," said MacDonald.