Nora Vanegas-Arroyave1, Denise F Chen2, Peter M Lauro3, Gina Norato4, Codrin Lungu5, Mark Hallett6. 1. Department of Neurology, Baylor College of Medicine, Houston, Texas, USA. 2. Department of Neurology, Emory University School of Medicine, Atlanta, Georgia, USA. 3. The Warren Alpert Medical School, Brown University, Providence, Rhode Island, USA. 4. Clinical Trials Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA. 5. Division of Clinical Research, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA. 6. Human Motor Control Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA.
Abstract
BACKGROUND: Parkinson's disease (PD) is associated with gait and visuomotor abnormalities, but it is not clear where PD patients look during ambulation. OBJECTIVE: We sought to characterize the visual areas of interest explored by PD patients, with and without freezing of gait (FOG), compared to healthy volunteers (HVs). METHODS: Using an eye-tracking device, we compared visual fixation patterns in 17 HVs and 18 PD patients, with and without FOG, during an ambulatory and a nonambulatory, computer-based task. RESULTS: During ambulation, PD patients with FOG fixated more on proximal areas of the ground and less on the target destination. PD patients without FOG displayed a fixation pattern more similar to that of HVs. Similar patterns were observed during the nonambulatory, computer-based task. CONCLUSIONS: Our findings suggest increased dependence on visual feedback from nearby areas in the environment in PD patients with FOG, even in the absence of motor demands.
BACKGROUND: Parkinson's disease (PD) is associated with gait and visuomotor abnormalities, but it is not clear where PD patients look during ambulation. OBJECTIVE: We sought to characterize the visual areas of interest explored by PD patients, with and without freezing of gait (FOG), compared to healthy volunteers (HVs). METHODS: Using an eye-tracking device, we compared visual fixation patterns in 17 HVs and 18 PD patients, with and without FOG, during an ambulatory and a nonambulatory, computer-based task. RESULTS: During ambulation, PD patients with FOG fixated more on proximal areas of the ground and less on the target destination. PD patients without FOG displayed a fixation pattern more similar to that of HVs. Similar patterns were observed during the nonambulatory, computer-based task. CONCLUSIONS: Our findings suggest increased dependence on visual feedback from nearby areas in the environment in PD patients with FOG, even in the absence of motor demands.
Authors: John G Nutt; Bastiaan R Bloem; Nir Giladi; Mark Hallett; Fay B Horak; Alice Nieuwboer Journal: Lancet Neurol Date: 2011-08 Impact factor: 44.182