The Reward Prediction System

Your dopamine system does not respond to rewards themselves — it responds to reward predictions. Better than expected? Dopamine surges. Exactly as expected? Moderate. Worse than expected? Dopamine drops.

This is the reward prediction error. A surprise bonus feels better than an expected one because the unexpected reward creates a larger prediction error — a bigger dopamine signal.

It also explains why repeated rewards lose power. First time you receive praise, dopamine spikes. Tenth time, the spike is smaller because the reward is predicted.