Neural Substrates for Vertical Saccade

  • Vertical saccades originate from burst neurons in the rostral interstitial nucleus of the medial longitudinal fasciculus (riMLF).
  • The riMLF, like PPRF, produces the phasic command.
  • Neurons in the interstitial nucleus (INC) convert this to a tonic command (like the pph for horizontal saccades).
  • The phasic and tonic commands combine in the MN's in III & IV n.
  • Both sides of the brainstem have neurons that generate upward saccades and others that generate downward saccades.
  • Do neurons on each side do the same thing; i.e. is this a redundant representation?