Scott Alexander explores the motivational system as described in 'The Hungry Brain', connecting it to dopamine, willpower, and predictive processing theory. Longer summary

Scott Alexander revisits Stephan Guyenet's book 'The Hungry Brain', focusing on its description of the motivational system. He explains how the basal ganglia in lampreys and humans select behaviors from competing 'bids' made by different brain regions. The post then discusses dopamine's role in this system and how disorders like Parkinson's disease and abulia affect motivation. Scott concludes by proposing a theory linking dopamine levels, willpower, and the predictive processing model, suggesting that high dopamine levels may represent confidence in overriding default behaviors with more willpower-intensive actions. Shorter summary