Content Chances of an accident. Fatigue and stress reduce the driver's ability to be able to process information in an orderly manner. The driver tends to look straight ahead and not carry out a search pattern. Her eyes will tend to drop so she will not be looking as far ahead. She is unlikely to carry out the IPDE procedure and, because her eye use and scanning will have deteriorated, she will have less time in which to react.
Passengers can serve to distract the driver.
Learn to put your driving first and have conversations as a second priority. As a passenger, learn not to interrupt the driver when conditions are difficult. Alcohol has similar effects on the driving task as do fatigue and stress. However, the effect is compounded by the fact that alcohol affects the perception of one's ability and, while a fatigued driver may know he is not driving well, an alcohol-impaired driver will believe he is driving well when this is not true. Their effects compound when combined with alcohol, and may be multiplied.