Ocular motor behavior of children with neurofibromatosis 1.
Patients with neurofibromatosis 1 show neurocognitive deficits including abnormal visuospatial performance, but oculomotor behavior has not been studied. We recorded saccades in neurofibromatosis 1 and normal children, ages 6 to 12 years. Patients showed increased latency and diminished amplitude to more eccentric targets for both visually guided and memory-guided saccades. Subtracting the latencies of visually guided saccades from memory-guided saccades produced no differences between groups. For predictive saccades (0.5 Hz), patients with neurofibromatosis 1 generated fewer anticipatory saccades than normal subjects, but patients with neurofibromatosis 1 made more direction errors in an antisaccade task. Patients with neurofibromatosis 1 show saccade abnormalities that are not easily ascribed to dysfunction within single cortical areas. Rather, the findings likely reflect (1) partial involvement of different components of a widely distributed cerebral network that controls saccades, (2) impaired visuomotor maturation in a brain abnormal early in development, and (3) excessive gamma-aminobutyric acid-mediated inhibition, which could influence basal ganglia pathways that modulate superior colliculus activity.
Lasker
Adrian G
AG
Department of Neurology, Johns Hopkins School of Medicine, The Johns Hopkins Hospital, Baltimore, MD 21287-6921, USA. alasker@dizzy.med.jhu.edu
Denckla
Martha B
MB
Zee
David S
DS
D001479:Basal Ganglia / Q000473:pathology; D002540:Cerebral Cortex / Q000473:pathology; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D009456:Neurofibromatosis 1 / Q000150:complications*; D012438:Saccades; D013028:Space Perception; D014796:Visual Perception