Heavy drinkers have a sense that excessive alcohol consumption isn’t doing them much good. But, paradoxically, they believe the rapid and complex visuomotor integration required for driving is unaffected. Presumably the lack of conscious access to the non-declarative habit systems of the brain (tell me exactly how to drive a car, play a musical instrument or ride a bike!) – which is true under normal circumstances – obtains, but the drunken driver is unable to consciously estimate the degree of their actual motor impairment – because they don’t know anyway. Because the habit system – based around the striatum – is not consciously accessible anyway!
We test whether heavy or binge drinkers are overly optimistic about probabilities of adverse consequences from these activities or are relatively accurate about these probabilities. Using data from a survey in eight cities, we evaluate the relationship between subjective beliefs and drinking. We assess accuracy of beliefs about several outcomes of heavy/binge drinking: reduced longevity, liver disease onset, link between alcohol consumption and Driving While Intoxicated (DWI), probability of an accident after drinking, accuracy of beliefs about encountering intoxicated drivers on the road, and legal consequences of DWI-ranging from being stopped to receiving fines and jail terms. Overall, there is no empirical support for the optimism bias hypothesis. We do find that persons consuming a lot of alcohol tend to be more overconfident about their driving abilities and ability to handle alcohol. However, such overconfidence does not translate into over-optimism about consequences of high levels of alcohol consumption. [emphasis added]