Ann Graybiel and crew show that the role of dopamine in reinforcement learning is not so straightforward. Rather than just give short bursts tied to reward prediction errors, dopamine ramps up as rats near a goal. It could reflect a motivational drive.
About the Author
The Miller Lab uses experimental and theoretical approaches to study the neural basis of the high-level cognitive functions that underlie complex goal-directed behavior. ekmillerlab.mit.edu