Dopamine functions as a currency for motivation and desire rather than just pleasure, with tonic baseline levels and phasic peaks that regulate one's subjective quality of life.

“Dopamine is a universal currency in all mammals, but especially in humans for moving us toward goals and how much dopamine is in our system at any one time compared to how much dopamine was in our system a few minutes ago, and how much we remember enjoying a particular experience of the past.”