1 in 5 Canadians With Vision Loss See Visual Hallucinations
When most people think of vision loss, they think of blindness. But a recent study conducted by Dr. Keith Gordon of the Canadian National Institute for the Blind found that a surprisingly high percentage of people with severe vision loss actually report seeing more than meets the eye.
The study, published in the Canadian Journal of Ophthalmology, found that 1 in 5 patients with vision loss caused by eye disease report experiencing vivid visual hallucinations. This phenomenon is known as Charles Bonnet syndrome (CBS) after the Swiss naturalist and philosopher who first described the syndrome in 1760. The visual hallucinations associated with CBS can range from animated, colorful, dreamlike images to less complex visions of people, animals, vehicles, houses, and similar everyday images.
The prevalence of the syndrome despite a generally low awareness of it is likely a result of those experiencing hallucinations being reluctant to tell anyone for fear of being labelled mentally ill. But these types of visions are not a sign of dementia – they are illusions, not delusions. CBS patients know that what they’re seeing isn’t real.
What’s actually happening is like an optic version of phantom limb sensation, where amputees report feeling limbs that are no longer there. The visual hallucinations are the result of the brain trying to ‘fill in the blanks’ visually when the eyes aren’t registering what it’s seeing.
And while these hallucinations can be distressing for patients who don’t understand why they’re seeing what they’re seeing, speaking about their experiences with eye care specialists can help put them at ease. Although there’s not yet a cure for Charles Bonnet syndrome, doctors hope that raising awareness will lead to better research, diagnosis and treatment methods.
If you’re concerned that you may be experiencing visual hallucinations as a result of vision loss, contact an FYidoctors near you.