Dopamine has a WIDE variety of effects in the brain, depending on what part of the brain you look at and what specific dopamine receptors are involved in the circuit.
In motor control areas, dopamine manages movement and especially fine control -- which is partly why Parkinson's patients have that tremor all the time, and why medicines that increase their dopamine levels can reduce the tremor and improve control.
It gets really interesting, though, when you look at the frontal cortex. The front areas of the brain, over the eyes, are important for personality and for emotion. (For example, frontal lobe seizures may NOT have any shaking, just uncontrollable outbursts of irrational anger....without having a dweeby AH death to blame for it)
Frontal areas depend on dopamine receptors for behavior/reward learning loops, and for pleasure in general. In fact many "uppers" like dexadrine and cocaine trigger responses in the frontal dopamine system for their "high."
Anyway, that combined influence on reward loops and pleasure ion general means that addctive behaviors are tightly tied to the dopamine system....and explains both why Parkinson's Disease patients are VERY unlikely to be addcitive gamblers, and why some dopamine active medicines used for Parkinson's include addictive behavior as side effects.
Bu that doesnt mean gamers, who know a little about behavior/reward cycles, are victims of chemistry. The brain LEARNS more than just facts, and it is incredible adaptive to what we throw at it. Behavior modification can change chemical levels in the brain....and for example kids growing up with lots of TV and video games have lower tolerance for delayed gratification, because of the instantaneous nature of the reward cycles they're been trained in
So, while it may be fair to say that we victims of Aces Crack likely have higher frontal dopamine levels -- our choices determine our behavior, NOT our chemistry.
It is nice to know, though, that we have a low risk of parkinsons disease....
Simaril
