Rapid eye movements reflecting neurological disorders.

The accuracy and velocity of voluntary saccades together with the velocity of fact phases of nystagmus were studied in 26 patients belonging to 4 groups with defined neurological disorders. Patients with speech disorders of the dyspraxia type, indicating the lesion in the left frontal cortex, showed a pronounced decrease in saccadic accuracy in combination with normal saccadic and quick phase velocity. Patients with pontine disorders showed a significant decrease in the peak velocity of saccades and quick phases of nystagmus while the accuracy of the saccades ranged from normal to severely disturbed. Patients with acute meningo-encephalitis showed increases in peak velocity of saccades and of quick phases of nystagmus and the accuracy was somewhat reduced. Patients with a labyrinthine disease showed normal velocity of saccades and of quick phases as well as normal accuracy of saccades.