Economists and neuroscientists often explain game playing by
assuming that humans try to predict the opponent's behavior
on the basis of her past choices. We try to question this
assumption in a Prisoner's Dilemma Game by using a
methodology which we call the “subtractive behavioral
method”. Our aim is to investigate which task features make
participants attend to the opponent's behavior or, on the
contrary, make them take into account only their own choices
and received payoffs. We find a critical effect of contextual
information and we derive some suggestions about the
methodology of brain imaging and behavioral game theory
experiments.
