Charles Bonnet Syndrome
Charles Bonnet was a
philosopher of the 18th century. Circa 1760, Bonnet noted that
his grandfather, who was of sound mind and good physical health, had
started to experience hallucinations. The only thing wrong with
his grandfather was that his vision had gradually declined over the
years due to cataracts. Bonnet reported that despite not being
able to see much, his grandfather could see bird cages, men, women,
tapestries, etc with excellent clarity. In the 1930’s a syndrome
was named after Mr. Bonnet to describe a condition in which psychologically
sound people with visual loss experience hallucinations.
Charles Bonnet syndrome
usually affects elderly people who have had a decline in vision, especially
when that decline is due to macular degeneration. Not all people
with a decrease in vision are affected, and it is unclear what determines
who will be affected. People with Charles Bonnet Syndrome know
that the images aren’t real, and it can be quite distressing - they
will often not tell anyone about what they are experiencing. Because
of this, the prevalence of Charles Bonnet Syndrome is not well known.
It is thought to be between 15-50% of people with moderate to severe
visual loss. It’s theorized that a lack of visual stimulation
causes the brain to produce it’s own images. It has been compared
to phantom limb symptoms after amputation, a condition in which people
report that can still feel their limb even though it’s not there.
People with Charles
Bonnet syndrome have reported seeing all sorts of phenomena, including,
people, bricks, animals, dream-like colorful animations, and lattice
work patterns. These hallucinations can last only a few seconds
or continue for most of the day, and people can experience just one
or a few hallucinations repeatedly. The hallucinations rarely
have any personal meaning associated with them and can persist for up
to several years. Usually the brain adapts to the visual loss
after about 18 months and the hallucinations will begin to reside.
In the mean time, there are a few ways to cope with the hallucinations
as reported by Charles Bonnet peer support groups. Some of those
methods include blinking repeatedly, moving the eyes around in all different
directions, turning on a light, looking directly at or looking away
from the hallucination, and even yelling or swatting at the hallucination.
It’s been documented that hallucinations can also be stopped completely
if the vision is improved.
Although there is no proven drug you can take to stop CBS hallucinations,
some medications for other problems have been successful in helping
people, including anti-depressants, drugs for epilepsy, Parkinson's
disease, dementia or mental health problems. However these drugs can
also have unwanted side effects. When you experience CBS, often
the most effective form of treatment can come from knowing that the
condition is due to sight loss and is not a mental health problem or
a symptom of another disease. Being informed about the condition
and sharing your experiences with friends or family can also help.
The best way to avoid
getting Charles Bonnet Syndrome is to keep your vision crisp with healthy
eyes. A healthy diet, exercise, and lifestyle can help in this
regards. Unfortunately, some eye diseases cannot be influenced
by a healthy lifestyle, so early detection via annual comprehensive
eye exams is the best way to reduce your risk of vision loss.
