The effects of striatal dopamine (DA) on behavior have been widely investigated over the past decades, with "phasic" burst firings considered as the key expression of a reward prediction error responsible for reinforcement learning. Less well studied is "tonic" DA, where putative functions include the idea that it is a regulator of vigor, incentive salience, disposition to exert an effort and a modulator of approach strategies. We present a model combining tonic and phasic DA to show how different outflows triggered by either intrinsically or extrinsically motivating stimuli dynamically affect the basal ganglia by impacting on a selection process this system performs on its cortical input. The model, which has been tested on the simulated humanoid robot iCub interacting with a mechatronic board, shows the putative functions ascribed to DA emerging from the combination of a standard computational mechanism coupled to a differential sensitivity to the presence of DA across the striatum. © 2014 Fiore, Sperati, Mannella, Mirolli, Gurney, Friston, Dolan and Baldassarre.
Keep focussing: Striatal dopamine multiple functions resolved in a single mechanism tested in a simulated humanoid robot
Frontiers media, Lausanne, Svizzera
Frontiers in Psychology 5 (2014). doi:10.3389/fpsyg.2014.00124
info:cnr-pdr/source/autori:Fiore, Vincenzo G.; Sperati, Valerio; Mannella, Francesco; Mirolli, Marco; Gurney, Kevin N.; Friston, Karl J.; Dolan, Ray J.; Baldassarre, Gianluca/titolo:Keep focussing: Striatal dopamine multiple functions resolved in a single