Presaccadic burst discharges of tecto-reticulo-spinal neurons in the alert head-free and -fixed cat.

Tecto-reticulo-spinal neurons (TRSNs) discharge high frequency bursts of action potentials prior to visually triggered gaze shifts made in the head-fixed (eye only moves) or head-free (eye and head move together) conditions. These high-frequency presaccadic bursts are weak or absent when the cat generates gaze shifts to non-visible remembered targets. TRSNs remain silent during spontaneously generated gaze shifts. The visually triggered gaze shifts, that are preceded by TRSN bursts are faster than gaze shifts directed at non-visible targets.