Figure 1.

Comparison of head velocities during a gait test with those from a head impulse test (HIT) and a typical rotating chair velocity profile. The upper trace shows the lower trunk roll movements during walking while rotating the head left and right in pace with gait. The lower trace shows the head velocity in comparison to two HIT records and one rotating chair record. Although the amplitude of head velocity is comparable in the HIT test, the accelerations are clearly faster for the HITs, slower for the rotating chair.