title: Effect of visual feedback on the occipital-parietal-motor network in Parkinson's disease with freezing of gait.
abstract: Freezing of gait (FOG) is an elusive phenomenon that debilitates a large number of Parkinson's disease (PD) patients regardless of stage of disease, medication status, or deep brain stimulation implantation. Sensory feedback cues, especially visual feedback cues, have been shown to alleviate FOG episodes or even prevent episodes from occurring. Here, we examine cortical information flow between occipital, parietal, and motor areas during the pre-movement stage of gait in a PD-with-FOG patient that had a strong positive behavioral response to visual cues, one PD-with-FOG patient without any behavioral response to visual cues, and age-matched healthy controls, before and after training with visual feedback. Results for this case study show differences in cortical information flow between the responding PD-with-FOG patient and the other two subject types, notably, an increased information flow in the beta range. Tentatively suggesting the formation of an alternative cortical sensory-motor pathway during training with visual feedback, these results are proposed as subject for further verification employing larger cohorts of patients.
authors.affiliation: Department of Neurosciences, University of California , San Diego, CA , USA.
authors.forename: Priya D
authors.initials: PD
authors.lastname: Velu
authors.affiliation: Cognitive Science Department, University of California , San Diego, CA , USA ; Swartz Center for Computational Neuroscience, University of California , San Diego, CA , USA ; Institute for Neural Computation, University of California , San Diego, CA , USA.
authors.forename: Tim
authors.initials: T
authors.lastname: Mullen
authors.affiliation: Electrical Engineering Department, University of California , San Diego, CA , USA.
authors.forename: Eunho
authors.initials: E
authors.lastname: Noh
authors.affiliation: Cognitive Science Department, University of California , San Diego, CA , USA.
authors.forename: Matthew C
authors.initials: MC
authors.lastname: Valdivia
authors.affiliation: Institute for Neural Computation, University of California , San Diego, CA , USA.
authors.forename: Howard
authors.initials: H
authors.lastname: Poizner
authors.affiliation: Computer Science Department, Technion , Haifa , Israel.
authors.forename: Yoram
authors.initials: Y
authors.lastname: Baram
authors.affiliation: Cognitive Science Department, University of California , San Diego, CA , USA.
authors.forename: Virginia R
authors.initials: VR
authors.lastname: de Sa
keywords: EEG-fMRI; FOG; occipital lobe; parkinsonian disorders; visual feedback