Why does the brain have a reward prediction error?

Its success runs deep. It has been supported by converging evidence from the firing of neurons, the release of dopamine, and the blood-flow seen in fMRI. That evidence has been gathered across diverse species, from humans, monkeys, rats, and bees. There is even causal evidence that forcing dopamine neurons to fire sends error signals in the brain, effects we can see in the behaviour of the animals whose dopamine neurons are being toyed with. The theory bridges data from the scale of human behaviour down to the level of single neurons. Unlike many theories for the brain, this one is properly computational, and makes multiple, non-trivial predictions that have turned out to be true. Dopamine and errors in predictions are intimately intertwined. <a href="https://medium.com/the-spike/why-does-the-brain-have-a-reward-prediction-error-6d52773bd9e7">Learn More</a>