Charles Bonnet syndrome can make you see things that aren’t there. Scientists think that this happens because the brain may be craving more images than it’s getting. Charles Bonnet syndrome happens in people with low vision.
Charles Bonnet syndrome (pronounced “bo NAY”) is a condition that happens when a person with low vision has visual hallucinations.
The eye’s retina facilitates the conversion of light into a visual message for the brain. When you’re not able to do this, your vision gets worse and you become more likely to develop Charles Bonnet syndrome.
The hallucinations can be simple, like bright-colored patterns that show up over everything you see. The medical term for this is unformed hallucinations.
You can also see more complicated things, like animals, buildings or people that don’t exist. The medical term for this is formed hallucinations.
Although scientists aren’t quite sure of the pathophysiology behind Charles Bonnet syndrome, they think that the hallucinations happen because lower vision reduces the number of images your brain gets. Your brain wants more images, so it uses memories to recall things that it’s seen or simply makes things up.
This can be worrisome and confusing if you don’t know what’s happening.
Charles Bonnet syndrome can affect people with conditions that cause vision loss, such as age-related macular degeneration (ARMD). One study indicated that more than 12% of people with ARMD will develop Charles Bonnet syndrome.
An estimated 1 in 2 people with severely impaired vision may develop hallucinations. Charles Bonnet syndrome can happen in anyone, but it’s more frequent in patients 80 years or older.
In addition to AMRD, other conditions related to developing Charles Bonnet syndrome include:
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The key symptom of Charles Bonnet syndrome is seeing hallucinations. These hallucinations may appear as:
The images may:
These visions usually happen without noise. They can continue for various lengths of time from seconds to minutes to hours.
Most people with Charles Bonnet syndrome know that what they’re seeing isn’t real.
People with Charles Bonnet syndrome can’t control the hallucinations.
The cause of Charles Bonnet syndrome is related to loss of vision. A main theory is that your brain wants images and isn’t getting enough, so it creates them.
Some studies have indicated that what you see suppresses some nerve activity in your brain. When your eyes aren’t supplying that type of suppression, nerve activity in the brain appears as visual hallucinations.
Risk factors for Charles Bonnet syndrome include:
Your healthcare provider or eye care specialist will take your medical history, ask questions about your symptoms and do thorough physical and eye examinations.
It’s possible to have hallucinations when you’re taking certain medications. It’s also possible to have hallucinations if you’re withdrawing from using drugs or alcohol. You can also have hallucinations after cataract surgery.
Your providers will want to eliminate any other conditions that could possibly cause hallucinations, such as Alzheimer’s disease, Parkinson’s disease, Lewy body dementia and schizophrenia.
Your providers may recommend neurological tests to rule out these other diseases.
There’s no cure for Charles Bonnet syndrome. Providers have tried medications but they didn’t work. Symptoms often improve with time, possibly because your brain becomes used to receiving fewer images to process. However, it may take years for the hallucinations to stop.
If you have Charles Bonnet syndrome, you may be able to manage symptoms better with the following tips.
You may want to blink your eyes or close your eyes. You might want to look away from the hallucination or stare at it. You can also try moving your eyes without moving your head, looking from side to side or up and down.
You may find it easier to deal with Charles Bonnet syndrome if you have brighter light, especially in the evenings.
It may help you to spend less time alone and spend more time with people. The people you spend time with should be people you can talk to about your life, including the images you’re seeing. You may want to find a support group to improve your connections.
Some people have found that their symptoms get worse when they’re under stress or don’t get enough rest. Try to get enough sleep and to develop other ways to relax and to relieve stress. These could include practices like meditation, deep breathing and learning to relax your muscles in a progressive way.
In addition to these suggestions, your provider may suggest anti-anxiety medications or antidepressants to help you deal with your emotions and uncertainties.
Since researchers don’t really know what causes Charles Bonnet syndrome, there’s no concrete way to prevent it. You may be able to reduce your risk by taking certain steps to preserve your vision. For instance, if you havediabetes, you can do your best to manage your blood sugar levels.
It’s very important for everyone to have regular eye exams. This is especially true as people age, since many of the causes of vision loss happen as people get older.
It’s important to have a good relationship with your ophthalmologist or other eye care provider.
There’s no cure for Charles Bonnet syndrome. It may disappear over time, but it may take one to two years to go away.
You may find it difficult to do some of your daily tasks or walk in places that you don’t know well if you’re seeing things that aren’t there. It’s important to tell your healthcare provider about it.
You may have many questions for your providers about Charles Bonnet syndrome. Some of them may include:
If you have Charles Bonnet syndrome, you see hallucinations and you know that they’re not real. If you have Anton syndrome, you can’t see but claim that you can. You tell people that you’re seeing things that you really aren’t seeing. You deny your blindness, which has often occurred after a cerebrovascular injury.
A note from Cleveland Clinic
You may be disturbed if you have low vision and you’re seeing things you know aren’t really there. You may have Charles Bonnet syndrome. You’ll want to discuss these images with your healthcare provider. They will be able to suggest some type of support group or other ways to deal with both your vision loss and the hallucinations. It’s very important to get a correct diagnosis of your condition so you can get the best treatment.
Last reviewed by a Cleveland Clinic medical professional on 09/15/2022.
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Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy