Visual System and Balance
Along with proprioception and vestibular function, the visual system plays an important role in the ability of an individual to control balance and maintain an upright posture. When these three conditions are isolated and balance is tested, it has been found that vision is the most significant contributor to balance, playing a bigger role than either of the two other intrinsic mechanisms. The clarity with which an individual can see his environment, as well as the size of the visual field, the susceptibility of the individual to light and glare, and poor depth perception play important roles in providing a feedback loop to the brain on the body's movement through the environment. Anything that affects any of these variables can have a negative effect on balance and mainting posture. This effect has been seen in research involving elderly subjects when compared to young controls, in glaucoma patients compared to age matched controls, cataract patients pre and post surgery, and even something as simple as wearing safety goggles. Monocular vision (one eyed vision) has also been shown to negatively impact balance, which was seen in the previously referenced cataract and glaucoma studies, as well as in healthy children and adults.
According to Pollock et al. (2010) stroke is the main cause of specific visual impairment, most frequently visual field loss (homonymous hemianopia- a visual field defect). Nevertheless, evidence for the efficacy of cost-effective interventions aimed at these visual field defects is still inconsistent.
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Famous quotes containing the words visual, system and/or balance:
“Nowadays people’s visual imagination is so much more sophisticated, so much more developed, particularly in young people, that now you can make an image which just slightly suggests something, they can make of it what they will.”
—Robert Doisneau (b. 1912)
“Loving feels lonely in a violent world,
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—Marge Piercy (b. 1936)
“Mental health depends upon the maintenance of a balance within the personality between the basic human urges and egocentric wishes on the one hand and the demands of conscience and society on the other hand.”
—Selma H. Fraiberg (20th century)