AI learning technique may illustrate function of reward pathways in the brain

A team of researchers from DeepMind, University College and Harvard University has found that lessons learned in applying learning techniques to AI systems may help explain how reward pathways work in the brain. In their paper published in the journal Nature, the group describes comparing distributional reinforcement learning in a computer with dopamine processing in the mouse brain, and what they learned from it. Prior research has shown that dopamine produced in the brain is involved in reward processing--it is produced when something good happens, and its expression results in feelings of pleasure. Some studies have also suggested that the neurons in the brain that respond to the presence of dopamine all respond in the same ways--an event causes a person or a mouse to feel either good or bad. Other studies have suggested that neuronal response is more of a gradient.