Responses of neurones in the brainstem raphe nuclei to stimulation of the cerebellar fastigial nuclei in the cat.

Stimulation of the fastigial nuclei of the cerebellum was found to excite units located throughout the raphe nuclei of the brainstem. Raphe spinal units with axons conducting at velocities below 20 m/s were either unaffected by fastigial nucleus stimulation or inconsistently excited at long latency. In contrast units with faster conducting spinal axons throughout the raphe and more dorsally in the reticular formation were excited by stimulation of the fastigial nuclei. Many of these units responded at short latency and followed high rates of repetitive stimulation.