INITIATION OF VISUAL-GUIDED RANDOM SACCADES AND REMEMBERED SACCADES IN PARKINSONIAN-PATIENTS WITH SEVERE MOTOR-FLUCTUATIONS

We studied the initiation of saccades to visual-guided random time and remembered targets in a group of nine Parkinsonian patients with seve re motor fluctuations and in 9 age matched control subjects. In contra st to a marked skeletomotor improvement during the ''on'' condition, s accadic latencies for both visual-guided random saccades and remembere d saccades were increased in the patients during the ''on'' condition compared to the ''off'' condition. This result of dissociation between skeletomotor and oculomotor function indicates that common concepts o f saccadic initiation in parkinsonian patients do not hold true in pat ients with severe fluctuations since dopaminergic stimulation seems to increase saccadic latencies in these patients.