**Fatigue** negatively affects a driver's reaction time, **increasing** it. This means that the driver takes longer to respond to stimuli such as a red traffic light or an obstacle on the road.

- **Fatigue** and **drowsiness** are two states that increase reaction time. When a person is tired, their ability to concentrate decreases, their movements become slower, and they have difficulty making quick and effective decisions while driving.

- **Fatigue** causes symptoms such as difficulty concentrating, reduced vision and hearing, and slower movements. All these factors contribute to the driver taking longer to react to traffic situations.

- **Drowsiness** also delays reaction time, as the driver may experience micro-sleeps, slow body movements, and a decrease in decision-making ability.

In summary, fatigue is a critical factor that **increases reaction time**, making driving more dangerous. It is important to recognize the symptoms of fatigue and drowsiness to avoid accidents.