Quentin J. M. Huys, Roshan Cools, Martin Gölzer, Eva Friedel, Andreas Heinz, Raymond J. Dolan, Peter Dayan. Disentangling the Roles of Approach, Activation and Valence in Instrumental and Pavlovian Responding. PLoS Computational Biology, 7(4), 2011. [doi]
Abstract is missing.