“When you see well, your brain is processing thousands of images a day, including those seen for only a split second. So when damage occurs to your vision, the brain can get creative and keep on generating images—filling in the poor quality ones coming from the eye. This is worrying! Some people fear that dementia is setting in!
These images are called CBS or Charles Bonnet Syndrome after the doctor who first reported them in 1760!
The images are generally benign, detailed, and tiny. Images of colored patterns and people are most common. Strangely, they can become part of what you are seeing. You’re watching TV and little green men start running up the screen. These visual releases can last just a few seconds or continue interfering with life. They tend to lessen over time but not for everyone. Blinking or standing up can chase them away, and there are more suggestions for lessening the effects at the Charles Bonnet Foundation. From my book: When You Can’t Believe Your Eyes: Vision Loss and Personal Recovery, published by Charles C. Thomas, (2019) Chapter 3.
This syndrome was also known as ‘visual release hallucinations’ but some people associate the word hallucination with mental abnormality, so the term has been somewhat discontinued. I like it because the ‘visual release’ part seems to capture what happens.
Last month some people wrote comments about CBS on my blog Vision Loss and Personal Recovery. These illusions happen to about a third of adults after significant sight loss.
From Sue B: “My husband has lost his vision due to glaucoma. When he first started experiencing hallucinations it was heartbreaking and terrorizing – I feared he had PD and/or AD. I carefully observed what was going on – when the hallucinations occurred and what he “saw.” Dr. Google and I made an accurate diagnosis – Charles Bonnet Syndrome. At his next visit with the glaucoma specialist I talked to her about it. She was matter of fact. Wasn’t surprised. WHY they don’t have brochures in the waiting area or mention to patients or their caregivers is hard to explain. Best answer is they don’t get paid a penny to spend a minute to discuss CBS.”
From Alan B: “At first, it was just geometric designs. Then, when walking outside, every bush and shrub was lavender color. Then, when I was working on my computer, I kept seeing at the bottom a pulsating tiger. That was freaky. Fortunately, after a few weeks, all the illusions disappeared. Just freaky and annoying. It took a while for him (or her) to go away and leave me be.”
From Miriam F “My husband thought everyone was about 2 feet high. Then he saw cartoon figures on the walls. It happened very frequently at first but not so much recently.”
If you or your partner or parent have experienced CBS please tell us about it Here’s the email: Hannah@VisionLossAndPersonalRecovery.com