Nissan says they improver ergonomics and lessen fatigue on long drives...
http://www.nissan-global.com/EN/TECHNOLOGY/OVERVIEW/zero_gravity_inspired_car_seat.html
http://www.nissan-global.com/EN/TECHNOLOGY/OVERVIEW/zero_gravity_inspired_car_seat.html
Ergonomic technology was utilized to analyze, measure and verify fatigue reduction and comfort, leading to the NASA-measured “neutral posture.” In a weightless scenario human posture is weakened and the burden on the body is at its least, meaning posture does not collapse even over long periods and you are less likely to become tired. By applying this neutral posture to a car seat, it alleviates feelings of fatigue from sitting for long periods of time.
