Regarding the influences of the driving environment on the perception of movement and speed, if you drive on a wide road with no elements on its margins:
You will tend to perceive a higher speed, so it is very likely that you will travel at more than 180 km / h .
You will tend to perceive a slower speed than if the road is narrow and lined with tall vegetation .
The characteristics of the environment do not influence the perception of movement and speed, so this is not something that you should take into account to circulate safely .