Charles Bonnet Syndrome (CBS) is a condition that some people get when they lose some or all their vision. It causes them to have visual hallucinations (seeing things that aren't really there). A new study suggests this condition is surprisingly common among people with certain types of vision loss.
What Causes Charles Bonnet Syndrome?
With healthy vision, light enters the eye and is received by the retina (the light-sensitive tissue in the back of the eye). The retina converts these light rays into visual messages, which are sent to the brain, so we can see.
When people lose vision from diseases like age-related macular degeneration, glaucoma, or diabetic retinopathy, their visual system doesn't process new images. Without visual data coming in through the eyes, the brain fills the void and makes up images or recalls stored images for you to see. This is what causes the visual hallucinations of CBS. It is very similar to how people who have lost a limb may feel phantom pain and is not a sign of a mental health problem.
What Are Symptoms of Charles Bonnet Syndrome?
The main symptom of CBS is having visual hallucinations. Most people have them when they wake up. What people see varies, but can include:
- repeating patterns of lines, dots, or other geometric shapes
- landscapes, such as mountains or waterfalls
- people, animals, or insects
- people dressed in costume from an earlier time
- imaginary creatures, like dragons
The hallucinations may move or remain still, and they can appear in black and white or color. The length of the hallucinations can last seconds, minutes, or hours.
How Is Charles Bonnet Syndrome Diagnosed?
There is no special test to find out if you have CBS. Your doctor will want to talk to you about your medical history. They will try to rule out other sources of visual hallucinations, including:
- whether you take certain medications
- mental health problems
- other neurological (brain) conditions
If you have vision loss and visual hallucinations without these other conditions, you likely have CBS.
There is no cure or effective medical treatment for Charles Bonnet Syndrome (CBS), but there are some techniques that can help you cope and manage the condition.
What you are seeing is not really there
People with CBS recognize that what they are seeing is not really there. With other causes of hallucinations, people may act on the hallucination. They do so because they believe that what they are seeing is real. You can feel reassured and less worried to know that your hallucinations come from vision loss.
Talk about your hallucinations
Whether you talk to your therapist, your doctor, a friend or a family member, describing your hallucinations to someone can make you feel less isolated. A CBS support group is also a great source of tips/coping strategies and a safe space to talk about your own experience with CBS. Also, simply reminding yourself or your loved one that the hallucinations are caused by vision loss and not the result of a mental health problem can be reassuring.
Change your environment
Do your hallucinations happen more often in dim lighting or in brightly lit rooms? If so, changing the lighting conditions may help reduce your hallucinations. For example, if they happen in dim light, turn on more lights or open the curtains. If you see the hallucinations when it’s very quiet, turning on a TV or radio may help.
Use your eyes
Some have found using the following techniques as the hallucinations begin can help stop them:
- Move your eyes up-or-down or side-to-side (without moving your head)
- Look away from the hallucinations
- Stare at the hallucinations
- Close your eyes and then open them
Rest and relaxation
Some people say fatigue and stress make their CBS worse. Be sure to get plenty of sleep and reduce anxiety with exercise, meditation or whatever you find helpful.
Seeing visual hallucinations can be upsetting—especially after losing your vision from another disease. But it's helpful to know that most people with CBS don't have scary or threatening hallucinations. Over time, the more you see the hallucinations, the more you will learn to manage them. In most cases, the hallucinations slow down considerably or stop after 1 to 2 years.