TORONTO -- The first time Jack Hunter realized that seeing wasn't really believing was about eight years ago, as he was sitting in his Toronto apartment reading and caught a flicker of movement across the room.
There, before his eyes, he beheld a woman cleaning the floor.
"All I could see was the profile of a woman standing there and one hand was going in and out negotiating the broom -- she was either sweeping or mopping the floor -- and I thought 'What the heck is this?'
"And the more I tried to turn my head to see, I saw less of it. And if I really looked hard, it disappeared altogether."
Hunter, an ex-cop from Scotland who emigrated to Canada 50 years ago and spent 35 years as a private detective investigating copyright infringement, isn't one given to flights of fancy. So he was more intrigued than alarmed.
"I wouldn't say I was afraid. I was a wee bit concerned," said the 77-year-old, who has lost sight in his left eye and has about 30 per cent vision in his right eye, the result of age-related macular degeneration and glaucoma.
At a scheduled appointment the next day, Hunter described the apparition to his ophthalmologist, who assured him such hallucinations were common among people with severe vision loss and he shouldn't worry.
Hunter later discovered his condition had a medical designation -- Charles Bonnet syndrome (pronounced bone-AY), named for the Swiss naturalist who first documented it in 1760 in his grandfather. The 89-year-old, who was nearly blind from cataracts, described seeing people, birds, carriages and buildings that didn't exist.
About one in five people with low vision experience Charles Bonnet syndrome, said Keith Gordon, vice-president of research at the CNIB, whose study on the condition's prevalence among about 2,500 patients seen at the Toronto centre is published in the current issue of the Canadian Journal of Ophthalmology.
But what was alarming to Gordon was how little awareness there seemed to be about the syndrome, both among medical professionals and the general public.
That dearth of knowledge can harm affected patients because many believe the hallucinations are caused by dementia or mental illness, he discovered while interviewing 35 subjects in a subsequent study.
"A lot of them said they would not tell people about it because they were afraid to admit that they were going crazy," Gordon said. "I think people need reassurance that they're not going crazy and what they're suffering from isn't a form of dementia."
Dr. Dominic Ffytche of King's College London, one of the world's foremost experts on Charles Bonnet syndrome, said the hallucinations are caused by hyperexcitability of neurons in parts of the brain that process visual images.
"So brain cells are firing when they shouldn't be ... (and) that leads to the hallucinations," Ffytche, a clinical senior lecturer in old age psychiatry, said Wednesday from London.
"Our visual brains are working all the time to decode what we're seeing in front of us, whether that's a face or an object. It's not a reliving of a visual experience that you've seen in the real world."
People with Charles Bonnet commonly describe similar types of images: geometric patterns like brick walls, birds and animals, gargoyle-like faces, and people dressed in elaborate Edwardian- or Victorian-era costumes or military uniforms. Napoleonic soldiers are a common "sight."
"We don't know why that is, but the assumption is there's a bit of the brain processing, maybe figure-perception, that when it fires off, it gives you a sense that there are figures in an old-fashioned costume," said Ffytche.
Unlike hallucinations related to dementia or some mental illnesses, those caused by Charles Bonnet syndrome do not have an auditory component, he added.
"It's like a silent movie, but they can have internal motion. They could be dancing or moving around or walking, for example."
Gordon said one woman saw little men holding umbrellas sitting on the end of her bed. Another described ranks of soldiers marching down the street.
"Some people like it, some are afraid and others hate it," said Gordon, noting that hallucinations can last from seconds to minutes and often occur a couple of times a day, sometimes for months, sometimes for years.
"Some are prepared to live with it and others just want to get rid of it."
There are no drugs that will banish the delusions, but Gordon said adjusting one's lighting and rapidly blinking or repeatedly moving the direction of one's gaze can make them disappear, at least temporarily.
The CNIB has a pamphlet explaining Charles Bonnet syndrome, which clients are asked to take to their primary-care doctor. They are also encouraged to have their physician confirm that the hallucinations are related to eye disease or conditions like stroke that affect visual pathways in the brain -- not Parkinson's or another neurological condition.
As for Hunter, he can no longer read or drive a vehicle -- but at least his experience with Charles Bonnet has been visually rich.
Towering castles where there was only an empty field and park; a young girl wearing a red dress with a big bow on the back, holding out her arms to someone; a man wearing khaki shorts and sandals, reading a broadsheet newspaper; and a fly that appeared inside his TV that flew out into his living room, became a bird, a bat, then a flock of flying birds before morphing into a brilliant red and blue cockatoo sitting on a tree branch.
"I find it very, very interesting," he said. "And they're so clear."
One day in his apartment, he saw three ladies with grey hair, all of them wearing long dresses from "the late 1800s or something," who appeared to be polishing furniture. One of them was up a ladder, reaching up to do some task.
Hunter has no idea why it's these kinds of objects and figures that appear to him, and he knows his friends are often incredulous when he describes these visual companions that come and go in the blink of an eye.
And that can include some good-natured ribbing.
"My friend says to me, 'Do you ever see anyone in a mini skirt?' Unfortunately, I've not been that lucky."
