Driving after smoking marijuana primarily affects a person's ability to do what?

Driving after smoking marijuana primarily affects a person's ability to make quick decisions. Marijuana can impair cognitive functions, including reaction times, decision-making abilities, and judgment. This impairment can lead to difficulties in assessing speed, understanding distances, and reacting promptly to changing driving conditions or unexpected events on the road.

While maintaining speed is important for safe driving, the ability to make quick and accurate decisions in response to the dynamic environment of driving is even more critical. For instance, if a driver encounters a sudden obstacle or needs to react to the behavior of other drivers, quick decision-making is essential to prevent accidents. The cognitive impairments from marijuana can hinder a person’s capacity to make these critical decisions effectively, which increases the risk of accidents and unsafe driving behavior.