Cristian Ducu's Key Ideas from The Molecule of More
by Daniel Z. Lieberman

In the beginning, Dopamine was perceived as the "pleasure molecule".

Participants in early researches had pleasure when Dopamine was activated.

Reputation was consolidated through more research on drug addicts, and it was named the reward circuit. 

Later, it was discovered that Dopamine is not an indicator of pleasure but a reaction to unforeseen, possibility, and anticipation. 

The Circuit of Dopamine was made to promote behaviors that lead us to survival and reproduction. 

Most dopamine neurons signal a reward prediction error; they are activated by more reward than predicted (positive prediction error), remain at baseline activity for fully expected rewards, and show depressed activity with less reward than predicted (negative prediction).

When everything is familiar, our enthusiasm fades away, and we are looking for new things.

For Dopamine, having is not what matters but getting something new. It's the difference between possessing something versus anticipating it and is designed to keep us alive and make us evolutionarily successful.