Fewer dopamine receptors makes for risky business 

Brain-scanning study in people sees link between personality, dopamine system

It seems preposterous that thrill seeker James Bond would have too few of anything, but new research suggests he may have a deficit of dopamine receptors.

Earlier work has suggested that a propensity for risky behaviors, like driving fast cars, gambling and drinking, is influenced by dopamine, one of the brain’s chemical messengers.