Effect of head pitch and roll orientations on magnetically induced vertigo

Lying supine in a strong magnetic field, such as in magnetic resonance imaging scanners, can induce a perception of whole‐body rotation. The leading hypothesis to explain this invokes a Lorentz force mechanism acting on vestibular endolymph that acts to stimulate semicircular canals. The hypothesis predicts that the perception of whole‐body rotation will depend on head orientation in the field. Results showed that the direction and magnitude of apparent whole‐body rotation while stationary in a 7 T magnetic field is influenced by head orientation. The data are compatible with the Lorentz force hypothesis of magnetic vestibular stimulation and furthermore demonstrate the operation of a spatial transformation process from head‐referenced vestibular signals to Earth‐referenced body motion.