Driving requires continuous decision-making and judgment can be affected by even small amounts of alcohol. Alcohol, a central nervous system depressant that is rapidly absorbed into the bloodstream, blocks messages trying to get to the brain. This alters a person's perceptions, emotions, movement, vision, and hearing.
Alcohol-impairment can cause a driver to take risks and make misjudgments about speed - resulting in taking turns too fast or maintaining an appropriate speed, braking properly, making illegal turns, improper and unsafe lane changes, or following another vehicle too closely. Alcohol-impaired drivers may drive at the edge of a roadway, on the shoulder, drive off the road, drive through turn-only lanes, or remain stopped for an unusually long period of time after a traffic signal has turned green.
