Written by Marissa Hoen | March 16 2021
With more than 50% of the brain’s surface involved in vision processing, the visual system is obviously complex. In this past semester at UVic, I’ve been taking a course that has us diving into the nitty gritty of the visual system and how we understand what goes on in the world around us by deciphering the light that enters the eye. Beyond the numerous thoughts about how and why we have eyes in the first place, this class has had me thinking: how can we use (or neglect) vision to improve our movement?
If you’ve ever tried balancing with your eyes closed, you’ve probably felt just how important vision is to your balance. Sometimes when I’m practicing my balance, I close my eyes and all of a sudden I’m sideways, and my body starts wobbling all over the place in an attempt to rebalance. As I start to fall I open my eyes and regain balance almost immediately! This reliance on vision is quite evident in most people who try balancing with their eyes closed, and has been reported in several studies (Paul, 2014; Dhoriyani, 2013).
Testing Balance with Visual Deprivation
After 4 weeks of balance training in participants who have had strokes, the group who practiced with eye masks showed greater balance improvements than those who practiced with free vision (Paul, 2014). This highlights the importance of training other systems involved in balance to reach ideal balance gains.
Balance is a two way street- the brain requires incoming sensory input to respond with proper neuromuscular output! Input comes from several sources:
Proprioceptors (or position detectors) around the joint and in the muscles and tendons
Vestibular system located in the inner ear, this system gives the brain feedback on the orientation of the head relative to the ground
Visual system involves eyes, muscles, and many brain areas to integrate information on orientation and position of our own bodies as well as identification of objects in our environment
When we limit visual input by closing our eyes, we are challenging proprioceptive and vestibular systems which improve function with training. Where there is challenge, there is growth!
In a study by Yang and Liu (2020), participants with MS were found to have greater balance difficulties with both eyes closed than in participants without MS. They also found that both groups relied more on proprioceptive cues than vision to maintain balance. When taking into account neurological challenges however, one size does not fit all. For example, though visual impairments are common for those with MS, they are not always present. An individual may have MS in the proprioceptive pathway and thereby have an increased reliance on vision for their balance.
So are you saying I should keep my eyes closed during my workout?
Not quite! If you are looking to solely increase your balance, there is evidence that supports visionless training. However, there are studies that promote the efficacy of augmented visual training (eyes open training with visual cues from a coach), specifically in those with Parkinson’s Disease in decreasing related symptoms and improving motor performance (Kearney et al., 2019). If you are training to make your daily life activities easier, then you should train task-specific exercises and utilize any sensory feedback you have (eyes open, look where you are going, be aware of body sensations). When this becomes easier and you are in a safe environment, you can try taking out vision and testing your spatial memory, proprioception, and balance.
Key Takeaways:
When you’re a beginner with a certain movement, visual cues can help you better learn that movement and may increase your performance after you’ve learned that skill.
Adding vision-less balance practicing to your workout can help to improve balance greater than eyes-open practice.
Try it all! Come in to MOVE and use the parallel bars for a safe way to practice balance and movements skills with or without vision!
References
Dhoriyani, N. B., Patel, F. B., Smitha, D., Kagathra, S., & Bhatt, K. (2013). A comparative study
of effectiveness of balance training with and without visual cues on activities of daily living in stroke patients. Indian Journal of Physiotherapy and Occupational Therapy, 7(3), 285-290. https://doi.org/10.5958/j.0973-5674.7.3.109
Kearney, E., Shellikeri, S., Martino, R., & Yunusova, Y. (2019). Augmented visual feedback-aided interventions for motor rehabilitation in parkinson's disease: A systematic review. Disability and Rehabilitation, 41(9), 995-1011. https://doi.org/10.1080/09638288.2017.1419292
Paul, J. (2014). Comparative effect of vision deprived balance training over free vision balance training among stroke subjects. International Journal of Physiotherapy, 1(2), 46-53.
Yang, F., & Liu, X. (2020). Relative importance of vision and proprioception in maintaining standing balance in people with multiple sclerosis. Multiple sclerosis and related disorders, 39, 101901.
Image credit: https://depositphotos.com/stock-photos/cartoon-eyes.html