At the biological level researchers have identified a neuropeptide that is associated with the feelings of love and care giving. It is called oxytocin and is often used to induce uterine contractions during childbirth. It also is know to flood our brains during moments of intimacy, especially when a mother is breast-feeding her baby or during intimate and loving sex. This is the bio-chemical that promotes attachments.
Oxytocin in the form of a nasal spray has been shown to reduce symptoms of social stress, increase trust and connection with others, especially those of our in-group. Oxytocin can also increase the powers of empathy and the ability to understand what others are thinking. A shot of oxytocin to the brain will increase the tendency to gaze in the eyes of others and help you remember the names of people you recently met.
Some studies with men who were avoidantly attached found that after only one dose of oxytocin they were more likely to respond as secure when assessing attachment images and phrases linked to security, comfort and safety with others. Even though this was a momentary shift, the researchers suggest that it could be used effectively in therapy sessions to promote changes toward secure attachment relationships over time.
So why isn't oxytocin more widely available for use to promote love and kindness? Well, as noted above the effects are temporary and only tested on men since oxytocin is can induce labor in women. Also oxytocin may have a dark side. In one study oxytocin was shown to promote ethnocentrism (the tendency to favor your in-group and disparage members of the out-group). So it seems that when people gather for a football game with other fans of a favored team oxytocin levels are driven up. Not only is there a feeling of solidarity with the other fans, but also there may be an increased dislike for those who are fans of the opposing team.
It seems that oxytocin evolved as a biological mechanism that helped our ancient ancestors identify whether others had a long -term commitment to the group.
A more recent study has shown that an external dose of oxytocin can change memories of how nurturing a person's mother was. The researchers found that the effects of oxytocin depended on the attachment representations people possess. Securely attached individuals remembered their mother as more caring and close after oxytocin (vs. placebo). In contrast more anxiously attached individuals remembered their mother as less caring and close after oxytocin.