Trust is essential to social interaction among humans.

Making friends, conducting business transactions, leading a team, and even playing games would be all but impossible without it. However, have you ever wondered why we trust other people at all?

Little is known about the science of trust, but researchers have begun to focus on the peptide oxytocin as a potential clue to the biological basis for this behavior. Oxytocin is produced in the hypothalamus, and acts on areas of the brain responsible for social behaviors. Scientists hypothesize that oxytocin stimulates a trust response by encouraging "approach behavior," or reducing the natural suspicion we have to the social proximity of others. The chemical has also been found to reduce the brain's fear response to pictures of human faces. Under its influence, people are more willing to take social risks.

In one study, researchers had their subjects play a simple game based on trust. Those who had been given a dose of synthetic oxytocin were more likely to trust the other players than those who had not. In another study, seventy individuals with general social phobias used synthetic oxytocin for one month, taking a dose before entering difficult social situations. These subjects were more relaxed and exhibited a higher level of confidence when interacting with others while supplementing their brain's natural levels of the chemical.

Scientists are hopeful that further research into the effects of oxytocin will provide a new way to treat anxiety disorders in humans, from debilitating shyness to autism and schizophrenia. As they continue to explore oxytocin's role in brain activity, they hope to further understand these disorders, as well as the normal function of trust in human societies.