Reading in a moving car can cause motion sickness (make you “car sick”).
Motion sickness relates to your sense of balance and equilibrium. Your sense of balance is maintained by a complex interaction of your inner ears, eyes, skin pressure receptors, muscle and joint sensory receptors, and the brain and spinal cord. Motion sickness can appear when the central nervous system receives conflicting messages from these four key bodily systems. When you read a book in a moving car, your inner ears and skin receptors detect the motion of travel, but your eyes see only the pages of your book.