If you are in a giving mood, it could be down to a neurotransmitter than your natural generous nature, particularly, if your kindness is directed to someone you are unlikely to meet again. Paul Zak of Claremont Graduate University has found new evidence linking the compound oxytocin to trust and generosity. Zak and colleagues dosed volunteers with oxytocin or a placebo in a blinded trial and then asked them to share out a sum of money with a stranger. The results were overwhelming, the researchers say, those given oxytocin offered 80% more money than those given a placebo. Oxytocin is well known as a female "feel-good" female neurotransmitter linked closely with mother to baby bonding.