Neuroeconomist Bill Harbaugh and his team at the University of Oregon study the biology of altruism. They look specifically at neuroeconomics, or the connection between the brain and economic decisions. In one of their experiments, the researchers tried seeing if people's donations to charity were affected by neurons. Nineteen women were given $100 to play a charity game on the computer. They could choose to donate or not to a charity, each decision leading to other situations where they could gain or lose money. At the end of the game, the subjects were able to keep all the money that was left in their accounts.