Dopamine, Affordance and Active Inference. - Karl J. Friston; Tamara Shiner; Thomas H. B. FitzGerald; Joseph M. Galea; Rick A. Adams; Harriet R. Brown; Raymond J. Dolan; Rosalyn J. Moran; Klaas Enno Stephan; Sven Bestmann (PLoS Comput. Biol., 2012)