Neuroeconomists have been busy with their scanners. Some recent papers from George Mason University (PNAS paper not yet free access) have found that players of a financial decision-making game are more likely to be fair in splitting money if they receive emotional feedback from playing partners. It is easier to be selfish, it seems, if we don't hear from our critics.
It's also interesting to see that it bothers our insula more if we know that our unfair game playing partners are people and not machines.
These studies have implications for the world of business and finance, but also our homes, classrooms, and online communities. People are more likely to be greedy or ruthless if they act anonymously, or are playing dominant and non-reciprocal roles. With the Internet the way it is, parents should be vigilant. There are definite dangers and temptations of the 'faceless' Internet.
Ultimatum Game and fMRI
Emotions and Fair Play