What symptom does marijuana prominently impair when driving?

Marijuana prominently impairs motor coordination when driving because it affects the central nervous system, leading to a decline in physical performance and reflexes. The active compounds in marijuana, particularly THC, can interfere with the brain's ability to process information and control movement effectively. As a result, drivers may experience slower reaction times, decreased balance, and an inability to perform tasks requiring fine motor skills, all of which are critical for safe driving.

While visual clarity, attention span, and hearing ability are indeed important cognitive and sensory functions that may be affected by marijuana use, the most significant impairment that directly impacts driving behavior is related to motor coordination. This impairment poses a greater risk on the road, as it affects a driver’s ability to react to sudden changes in traffic conditions or obstacles, which can lead to accidents.