In follow-up studies, other scientists also inhibited the dopamine-releasing parts of the brain, but this time, they squirted little droplets of sugar into the mouths of the dopamine-depleted rats. Their little rat faces lit up with pleasurable grins from the tasty substance. Even though dopamine was blocked, they liked the sugar just as much as before; they just didn’t want it anymore. The ability to experience pleasure remained, but without dopamine, desire died. And without desire, action stopped.
