What is dopamine?

Dopamine — the most talked-about human neurotransmitter — isn't a "love drug", or a "lust drug", or an "addiction drug", writes Bethany Brookshire in a smarter-than-average neuroscience story at Slate. It's actually a lot more complicated than that, and if you keep trying to pigeonhole and oversimplify what it does, you're going to completely misunderstand how your brain works.