system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What causes feeling nauseas when you read whilst a passenger in a car?
gpt
Your eyes see words on a page, which do not move.  They send "not moving" to the brain.  Your ear's balance mechanism feels the car's motion.  They send "moving" to the brain.  The brain compares these two signals and says "Oh no, there is a problem.  It's probably some poison berries you ate." and sends out the "Barf, barf now" command.

When you are driving, you are watching the road, so the eyes send "moving", and there is no problem.