Existing behavioral studies of inter-temporal choice suggest that both human and animal choosers are impulsive. One possible explanation for this is that they discount future gains in a hyperbolic or quasi-hyperbolic fasion (Laibson, 1997; Frederick, Loewenstein and O'Donoghue, 2002). This...

The neurotransmitter dopamine is central to the emerging discipline of neuroeconomics; it is hypothesized to encode the difference between expected and realized rewards and thereby to mediate belief formation and choice. We develop the first formal tests of this theory of dopaminergic function,...