[Slowed saccades in various neurological disorders]

4 patients suffering from different neurological disorders are presented, exhibiting a striking slowing down of all saccades. According to their clinical features the problem of slow saccades of supranuclear origin is discussed, to elucidate the question whether these eye movements are saccadic at all. Electro-oculographic traces served to distinguish these particular eye movements, and a computer calculated duration, velocity and acceleration of these saccades, to identify their saccadic nature. 1 patient with Wernicke syndrome showed a remarkable improvement of saccadic velocity following thiamine administration. The findings are reconciled with known saccadic behavior, and a model of the pathophysiological mechanism is cast. The adaptability of the system nearly back to normal in the case of Wernicke syndrome is stressed.