A PATHWAY MEDIATING VESTIBULAR AND VISUAL INPUTS TO SACCADIC BURST NEURONS

The Physiological properties of burster-driving neurons (BDNs) located in and near the prepositus hypoglossi nucleus were investigated in th e alert cat. BDNs discharged in burst fashion for saccades and quick p hases of vestibular and optokinetic nystagmus directed to the contrala teral side. BDNs received strong excitation from the contralateral hor izontal semicircular canal and from the ipsilateral superior colliculu s. The response of BDNs evoked by superior colliculus stimulation was significantly modulated during horizontal head rotation. The results s uggest that the pathway through BDNs is closely involved in the genera tion of horizontal rapid eye movements and plays an important role in coupling the vestibular and visual inputs.