by Rukmini Tilara

Created on: May 03, 2008   Last Updated: June 29, 2009

The world's oldest known drug, ethyl alcohol, continues on its path of intoxication. However, Bacchus' revelry has given way to a grave threat to the human race. While wreaking havoc on the human body, it would not be an understatement to say that alcohol's effects are most horrifying when they are recklessly combined with driving.

A central nervous system depressant, alcohol acts at many sites in the brain and on many neurotransmitter systems. In low to medium doses alcohol -

impairs concentration
slows reaction time
reduces coordination
produces drowsiness
impairs vision

Chronic alcohol abuse causes
damage to the frontal lobes of the brain
overall reduction in brain size
"Wernicke's Encephalopathy" and "Korsakoff's Syndrome"

Human cognitive abilities are affected by even small amounts of alcohol. Brain cells associated with a multi-tasking activity like driving, such as memory, attention, coordination, and judgment are most vulnerable. However, many factors such as age, gender, medications and drinking patterns determine to what extent a person will be affected. Studies point to higher fatality rates among women than men at similar blood alcohol concentrations. Laboratory studies of response to visual cues and other tasks suggest that there may be gender differences in how alcohol affects the performance of driving tasks. In youngsters, roadside surveys indicate that, especially at low and moderate BAC's (Blood Alcohol Level) the crash rates are substantially higher than those of other groups. However, driving inexperience and immaturity are considered to be the main culprits and not alcohol impaired judgment.

A review of 112 studies concluded that certain skills required to operate essentially any type of motorized vehicle become impaired at even modest departures from zero BAC. Starting at BACs of 0.05 percent, drivers show impairment of eye movement, glare resistance, visual perception, information processing, reaction time and and other aspects of psycho motor performance. Night vision is most severely affected. Reduced depth perception (accurate judgment of distance from objects) and contrast sensitivity (detection of obstacles in the way) lead to further miscalculations and fatalities.

Thus alcohol continues on its rampage, increasing its toll each year. Sadly, the intoxicated brain, the primary instrument of destruction, is too far gone to even comprehend the extent of the damage it has done.

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