What is the purpose of head restraints in vehicles?

Head restraints play a crucial role in vehicle safety, particularly in protecting passengers from neck injuries during rear-end collisions. They are designed to limit the backward movement of the head in the event of a crash, which helps to reduce the likelihood and severity of whiplash injuries. Whiplash occurs when the head is abruptly thrown backward and then forward, causing strain on the neck muscles and ligaments. By keeping the head closer to the seat back, head restraints help to minimize this movement, thereby helping to protect the occupant's spine and neck.

In contrast, options that suggest head restraints enhance driver comfort, assist with headlight alignment, or improve aerodynamics do not accurately reflect their primary function in vehicle safety. The primary focus of head restraints is indeed on preventing injury during certain types of collisions, particularly rear-end impacts.