ScienceDaily -- A study by researchers at Universidad Carlos III de Madrid and Universidad de Zaragoza has determined that when deciding whether to cooperate with others, people do not act thinking about their own reward, as had been previously believed, but rather individuals are more influenced by their own mood at the time and by the number of individuals with whom they have cooperated before.
MORE: http://www.sciencedaily.com/releases/2012/07/120704124059.htm
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Brain Center for Social Choices Discovered: Poker-Playing Subjects Seen Weighing Whether to Bluff
http://www.sciencedaily.com/releases/2012/07/120705181248.htm
