TY - JOUR

T1 - Abnormalities of Nonvisually-Guided Eye-Movements in Parkinsons-Disease

AU - Crawford, T. J.

AU - Henderson, L.

AU - Kennard, C.

PY - 1989/12/1

Y1 - 1989/12/1

N2 - Rapid eye movements (succades) were examined in 7 patients with idiopathic Parkinson's disease (PD) and a matched group of normal control subjects. The effect of instructional and stimulus conditions used to elicit saccades was examined using 3 experimental paradigms. Eye movements directly elicited by a novel peripheral target were unimpaired in patients with PD as compared with control subjects. Saccades to a remembered target location, however, were dysmetric in the PD group and showed a characteristic multistepping pattern. The PD impairment was not caused by a loss of information on target location since their final eye position was close to the target at all eccentricities. Peak velocity, duration, and latency did not distinguish between PD patients and controls. These results support the view that for saccades which are not directly elicited by a visual target there is a neural pathway that can be distinguished from structures involved in the generation of visually elicited (or ‘reflexive’) saccades The finding that in PD saccades to a remembered target are selectively impaired suggests that structures in the basal ganglia play a crucial role in this alternative pathway.

AB - Rapid eye movements (succades) were examined in 7 patients with idiopathic Parkinson's disease (PD) and a matched group of normal control subjects. The effect of instructional and stimulus conditions used to elicit saccades was examined using 3 experimental paradigms. Eye movements directly elicited by a novel peripheral target were unimpaired in patients with PD as compared with control subjects. Saccades to a remembered target location, however, were dysmetric in the PD group and showed a characteristic multistepping pattern. The PD impairment was not caused by a loss of information on target location since their final eye position was close to the target at all eccentricities. Peak velocity, duration, and latency did not distinguish between PD patients and controls. These results support the view that for saccades which are not directly elicited by a visual target there is a neural pathway that can be distinguished from structures involved in the generation of visually elicited (or ‘reflexive’) saccades The finding that in PD saccades to a remembered target are selectively impaired suggests that structures in the basal ganglia play a crucial role in this alternative pathway.

U2 - 10.1093/brain/112.6.1573

DO - 10.1093/brain/112.6.1573

M3 - Journal article

VL - 112

SP - 1573

EP - 1586

JO - Brain

JF - Brain

SN - 0006-8950

IS - 6

ER -