Which aspect of vision is affected first by fatigue, drugs, and speed?

Peripheral vision is often the first aspect of vision to be affected by fatigue, drugs, and speed. This is crucial for drivers to understand as peripheral vision plays a vital role in detecting movement and hazards outside the direct line of sight, such as other vehicles, pedestrians, or obstacles on the road. When a driver experiences fatigue or is under the influence of substances, their ability to notice these peripheral cues diminishes, leading to potentially dangerous situations.

As speed increases, the ability to process visual information is also impacted, which may cause the driver to overlook important details in their surroundings. Since peripheral vision is responsible for alerting drivers to changes outside of their immediate focus, any impairment in this area can significantly decrease situational awareness and reaction time, elevating risks on the road. Thus, recognizing the vulnerability of peripheral vision is essential for maintaining safe driving practices.