How does dopamine affect decisions and happiness?

Boosting dopamine with the drug levodopa increased how willing people were to take risks and how happy they felt about the rewards they received. Subjects made choices between safe and risky options and made more risky choices to try to get big rewards after taking the drug. They also felt happier after getting small rewards after taking the drug than they did after getting the same small rewards after taking a placebo. These results suggest that dopamine plays specific roles both in the decisions we make and how we feel about the outcomes of our decisions. [UCL press release], 

Rutledge RB, Skandali N, Dayan P, Dolan RJ (2015) Dopaminergic modulation of decision making and subjective well-being. Journal of Neuroscience 35, 9811-9822. [Abstract] [PDF]

Press: Journal of Neuroscience press release, The Independent (UK), Medical Daily (USA), Spektrum der Wissenschaft (Germany).