"And that, we assume, would have been a dopamine-driven response," Koob says.
In this sense, dopamine seems a sort of Pollyanna among neurotransmitters: It only really responds to the good stuff.
It seems logical to ask, then: If a person is born with a highly responsive dopamine system, wouldn't he or she be more tuned to receiving pleasure, to feeling rewarded?
Would, in turn, the person with a sluggish response tend to be unmotivated and less exuberant overall?
But like all roller-coaster rides, dopamine highs have their dangers.And what creates that outlook--the dopamine itself, the receptors that process dopamine's chemical messages, or some combination of the two?These are questions researchers are still sorting through.Starting in the mid-brain and reaching to structures such as the basal ganglia, dopamine clearly functions as a kind of spark plug, initiating motor behavior.When the spark fails, the brain's ability to order appropriate muscle movement fails, too.