What is a common symptom of drowsiness when driving?

Slowed reflexes are a well-documented symptom of drowsiness while driving. When a driver is fatigued, their reaction time decreases significantly, which can lead to delayed responses to sudden changes in traffic conditions or obstacles on the road. This impairment can make it difficult to respond quickly to critical situations, increasing the risk of accidents.

In contrast, increased heart rate, yelling at other drivers, and rapid breathing are not typically associated with drowsiness. An increased heart rate might suggest stress or anxiety rather than fatigue, while yelling can indicate frustration or aggression but does not point directly to drowsiness. Rapid breathing can be a response to stress or excitement, which is also unrelated to the effects of fatigue while driving. Understanding that drowsiness primarily impacts reaction time is crucial for maintaining safety on the road.