Predictive control of eye movements in parkinson disease

Flowers, Kenneth; Downing, Angela

doi:10.1002/ana.410040112

Cited by 24 publications

(13 citation statements)

References 7 publications

(5 reference statements)

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“…Our patients were obviously able to extract information about future target movement from the static visual cue. This finding resembles prior observations showing that parkinsonian patients can predictively induce smooth pursuit movements on the basis of temporal information acquired during antecedent trials [13]. However, the patients in the present study showed a major deficit with the accurate timing of the movement onset, which was significantly later than that of the controls but still earlier than without the street.…”

Section: Discussionsupporting

confidence: 89%

Parkinsonian patients show impaired predictive smooth pursuit

Ladda¹,

Valkovič

Eggert³

et al. 2008

J Neurol

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To determine if patients with Parkinson's disease (PD) are able to use a visual contextual cue to induce a predictive change in smooth pursuit direction and if this ability depends on the state of the dopaminergic system, we measured predictive smooth pursuit in nine patients with mild to moderate PD during OFF and ON medication. These values were compared with those of nine age-matched and sex-matched healthy controls.Our focus was on the horizontal smooth pursuit when subjects pursued a downward moving target entering a+/-90 deg curve. The target moved on a homogeneous background or on a static "street" that indicated the future trajectory of the target. Our main result is that PD patients were impaired in eliciting predictive smooth pursuit using the context information of the street compared to healthy subjects. The control group elicited predictive pursuit 250 ms before target onset. In contrast, PD patients showed significantly longer latency (100-120 ms) and reduced maximal pursuit velocity. However, without the street guiding pursuit, a delay of about 250 ms was seen in both groups. There was no significant difference in the smooth pursuit performance between OFF and ON medication in the patient group.These results show that early stage PD patients are impaired in the use of static visual information as a cue for predictive pursuit compared to controls and that this deficit does not depend on dopaminergic medication. In the context of predictive eye movement, the involvement of the striatal-frontal pathway and the spatial working memory is discussed.

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Section: Discussionsupporting

confidence: 89%

Parkinsonian patients show impaired predictive smooth pursuit

Ladda¹,

Valkovič

Eggert³

et al. 2008

J Neurol

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“…This distinguishes them from other parkinsonian syndromes (e.g., multisystem atrophy or genetic Parkinson syndromes) 17, 18. Predictive smooth pursuit responses were found to be intact, even in those PD patients who showed a loss of predictive control in manual tasks5 or a deficient capacity of generating anticipatory saccades 6…”

Section: Discussionmentioning

confidence: 99%

“…To date, it is not quite known whether PD patients are capable of (1) anticipating future events before an external trigger appears (i.e., anticipation) and (2) predicting movement velocity once the moving target shortly disappears from the visual scene (i.e., prediction). Previous studies suggested that PD patients are able to predict forthcoming smooth pursuit velocity on the basis of temporal information acquired during ongoing pursuit or antecedent trials 5–8. However, predictive smooth pursuit in PD patients in the latter studies has only been studied by latency and phase‐lag analysis of sinusoidal pursuit or pursuit ramp recordings.…”

mentioning

confidence: 99%

Role of anticipation and prediction in smooth pursuit eye movement control in Parkinson's disease

et al. 2012

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Patients with Parkinson's disease (PD) have difficulties in the control of self-guided (i.e., internally driven) movements. The basal ganglia provide a nonspecific internal cue for the development of a preparatory activity for a given movement in the sequence of repetitive movements. Controversy surrounds the question of whether PD patients are capable of (1) anticipating (before an external trigger appears; i.e., anticipation) and (2) predicting movement velocity once a moving target shortly disappears from the visual scene (i.e., prediction). To dissociate between these two components, we examined internally driven (extraretinal generated) smooth pursuit eye movements in PD patients and age-matched healthy controls by systematically varying target blanking periods of a trapezoidally moving target in four paradigms (initial blanking, midramp blanking, blanking after a short ramp, and no blanking). Compared to controls, PD patients showed (1) decreased smooth pursuit gain (without blanking), (2) deficient anticipatory pursuit (prolonged pursuit initiation latency; reduced eye velocity before target onset in the early onset blanking paradigm), and (3) preserved extraretinal predictive pursuit velocity (midramp target blanking). Deficient anticipation of future target motion was not related to either disease duration or the general motor impairment (UPDRS). We conclude that PD patients have difficulties in anticipating future target motion, which may play a role for the mechanisms involved in deficient gait initiation and termination of PD. In contrast, they remain unimpaired in their capacity of building up an internal representation of continuous target motion. This may explain the clinical advantage of medical devices that use visual motion to improve gait initiation (e.g., "PD glasses").

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“…Inferences of prediction in the pursuit eye movements of Parkinson’s disease have been based mostly on changes in phase error. In a study of predictive ability in patients with Parkinson’s disease, Flowers23 and Flowers and Downing24 suggested that although these patients showed evidence of impaired predictive control in a manual task, their predictor mechanism for the control of smooth pursuit eye movements was intact. In another study, Bronstein and Kennard10 found no impairment of prediction in the smooth pursuit system of Parkinson’s disease.…”

Section: Discussionmentioning

confidence: 99%