While self-driving cars bring the promise of being able to sit back and enjoy the scenery for some would-be drivers, those who suffer from car sickness may feel apprehensive at the prospect of long rides where the machine does most of the driving. To ease their pain, and the pain of other passengers, Japanese auto supplier NHK Spring says it has found the cure: a car seat that minimizes motion sickness for passengers in autonomous vehicles. The headrest supports the occipital bone behind the ear from both sides, the company says, keeping the head steady when the vehicle speeds up or slows down, or when the wheels hit a curve--situations that can trigger symptoms for people with motion sickness. Motion sickness is caused when visual information does not match motions picked up by the inner ear. Minimizing the motion of the head postpones the onset of symptoms--such as stomach discomfort, nausea and yawning--by about threefold the normal length of time, according to NHK Spring, which will sell the seat to automakers.