The chemical often referred to as the bonding hormone has already been shown to affect the social skills of people with autism.

For people who have a tough time in social situations, taking a whiff of the hormone oxytocin may help them feel a little extra extroverted. Oxytocin, which has also been shown to affect the social skills of people with autism, is often referred to as the mother-infant "bonding hormone." It is secreted in large quantities directly after childbirth and seems to promote the bonding of mother and child.

A new study set out to determine whether oxytocin would affect how open and outgoing people felt. The participants inhaled the hormone -- or placebo -- and then took a test 90 minutes later to measure "Big Five" personality traits: neuroticism, extroversion, openness to new experiences, agreeableness, and conscientiousness.

"Participants who self-administered intranasal oxytocin reported higher ratings of trust and openness to experiences than those who received a placebo," says author Christopher Cardoso. They ranked higher in factors like "warmth, trust, altruism, and openness." But there was no effect on "negative emotionality, conscientiousness, rejection sensitivity, depression, worry, self-esteem, and perceived social support."