How does the perception of speed change in foggy weather

Many dangerous traffic accidents occur in foggy weather. Therefore, drivers know that they need to reduce their speed in foggy weather conditions where visibility is significantly reduced. However, research shows that fog causes us to perceive the speed of objects moving around us differently than they actually are.

One of the most important data sources in the formation of the perception of speed in our brains is the movement of moving objects in our environment, for example trees or buildings, while passing through our field of vision. Decreased clarity of moving objects causes an erroneous sense of speed in the brain. Objects that look blurry when passing through our field of vision are perceived as moving more slowly than objects that appear clear.

Some scientists think that a similar effect occurred while driving in foggy weather. In foggy weather, people often drive slower than usual. However, fog causes the surrounding objects to be more blurred and difficult to see. This can lead to the impression that drivers are moving slower than they actually do. As a result, although the drivers think that they have reduced their speed in foggy weather, they may not be moving slowly enough.