Topic: Temporal-difference reinforcement learning

Temporal-difference reinforcement learning proposed that dopamine signals reward prediction errors, which backpropagate scalar values inherent in rewards to reward-predictive cues. This theory is supported by studies of dopamine activity in cue-reward learning, where a reward-paired cue acquires the dopamine response previously evoked by the reward. However, dopamine has recently been implicated in backward reward-cue learning. Specifically, a recent optogenetic study used a backward conditioning paradigm, where sensory cues are presented following the delivery of rewards, and showed that inhi