Modelling transfer characteristics of vestibular neurons in the fastigial nucleus of the behaving monkey on the basis of canal-otolith interaction.

The interaction of vestibular inputs with different dynamic and spatial behavior, i.e., canal-otolith interaction, leads to spatio-temporal convergence. Vestibular neurons in the fastigial nucleus often exhibit spatio-temporal convergence. The present report demonstrates that the discharge rates of most vestibular neurons in the primate fastigial nucleus can be simulated at different stimulus frequencies and orientations by a simple linear summation of the signals of the semicircular canals and the otoliths. In this way, a number of complex characteristics that depend on frequency, i.e. changing response-vector orientations, large phase changes, absence and presence of spatio-temporal convergence, can be easily explained.