Freezing in Parkinson’s – Beyond motor impairment?
Freezing is a common motor symptom of people with Parkinson’s Disease, where one is suddenly unable to move, or initiate a step. It usually happens when walking through a doorway, walking in a narrow confined space, or in a crowded situation.
From a recent Insight 2020 webinar, Dr Shaikh (2020) explained that freezing in Parkinson’s is not just due to motor impairment but is a multisystem affair which also involves Visual and Spatial perceptual impairment in Parkinson’s. Action and perception are closely linked together when performing a task. When there is an unbalance between the action and perception, or a disruption in perception, it can lead to action problem, such as freezing of gait.
Visual perception impairment in Parkinson’s
- Binocular misalignment, which is the misalignment of the eyes positions, is quite common in Parkinson’s. It can cause poor depth perception, poor convergence ability and double vision
- Impaired microsaccade movement rate of the eyes, which is a fast eye movement during visual scanning. People with Parkinson’s are found to have increased microsaccade movements or the eyes. They have decreased coordination of saccade movements.
- Abnormal perception of motion. People with Parkinson’s have decreased ability to perceive their own movements.
It is possible that visual and perceptual impairment play a part in the gait abnormality of Parkinson’s. Treatment towards perceptual non-motor function, such as exercises or Deep Brain Stimulation, may be helpful to improve gait abnormalities.
Shaikh A. (Producer). (2020). Freezing of gait- Why and how [Video webinar]. Retrieved from https://insight2020.vfairs.com/en/hall#topics-tab