I’ve just finished reading Hallucinations by Oliver Sacks and, like all his books, it’s an illuminating mixture of science and personal stories. The main takeaway is this: that it is more usual to have hallucinations of some kind, at some point in your life, to a greater or lesser degree, than to never experience hallucinations at all.
So, why don’t we talk about this? The answer is obvious. There is such a stigma attached to hallucinations that, if we were to drop them into conversation, people might think we were “going mad” or “losing it”. People usually equate hallucinations with psychosis. Hallucinations can certainly be part of psychosis. But psychosis is more complicated than that, and hallucinations can and do happen all the time to people who are not experiencing psychosis.
For example, me. If you’ve read my blog before, you’ll know I’m a migraine sufferer. Fortunately, I don’t get the “visual aura” that many migraine sufferers experience before or during attacks (these are counted as very common hallucinations) - but I did once have an olfactory hallucination.
It was a few days before Christmas and I had finished work for the year. I was busy getting the house ready for guests when I noticed this awful stench. It was like rotting meat mixed with a week-old bin. I emptied the bins and washed them out, though they didn’t seem to be causing the offensive smell. I checked my shoes. I checked everyone’s shoes. I interrogated bags and forgotten corners and looked in cupboards and tried in vain to work out where it was coming from. Eventually I blamed the cats. They’d obviously brought something in, eaten half of it, and left the other half to fester somewhere.
I began to embark upon a campaign to move heavy objects of furniture, sure I would find a half nibbled creature somewhere - but as soon as I enlisted the help of family members for this task, they were quick to point out they couldn’t smell anything.
“But it stinks!” I protested. “And our guests are going to think it’s disgusting!”
I assumed they’d gone “noseblind” through living with the stench, and set about filling the house with scented candles and essential oils, which did seem to help. When everyone arrived on Christmas Day, and I was all like “Happy Christmas - sorry about the smell”, they seemed to have no idea what I was referring to. I took that as proof that I’d done a really good job with the candles.
I soon realised, however, that the smell persisted outdoors. It must be me, I thought, with no small degree of horror. I must be the stinker. However, my family are pretty blunt about things like that, and definitely would have told me. I checked with them nonetheless: but nope, my aroma was definitely shampoo and deodorant, and not garbage.
Then I returned to work in the new year and the stench was there, too. It was also in the shops and the park and the library. It disappeared for short periods, sometimes at home, and sometimes elsewhere, but it was there for a large part of each day.
Just as I began to wonder if I should visit a doctor, the smell disappeared altogether, along with the onset of my first ever cluster headache. If you’ve never had one, this is a type of migraine headache where you experience sharp shooting pains (for me, just in one temple) for maybe 30 seconds to a minute, followed by a few minutes of respite. It’s not very nice, but I did prefer it to my usual relentlessly piercing migraine, which can stretch over days and make me feel awful. The cluster headache lasted two weeks and then disappeared, too. I’ve never had one - or an olfactory hallucination - since, but what’s stayed with me is how real the smell was to me and how unable I was to distinguish it from the actual real life smells other people could detect too. It turns out it’s fairly common to have olfactory hallucinations with migraine - though visual ones are far more common.
I can only imagine how confusing visual or auditory hallucinations might be. In his book, Sacks explores the different types of hallucinations - always with fascinating case studies - and why they occur. This is something neuroscience is very much still investigating as there is still so much to understand, but since the advent of fMRI scans we have access to a great deal more information.
Many people know that hallucinations are commonly experienced as part of dementia or Parkinson’s Disease, and lots of us will be familiar with the disorienting effects of high fever, which can also induce hallucinations. In my early counselling training I worked with visually impaired people and learned about Charles Bonnet Syndrome - a condition where the blind or partially sighted suddenly ‘see’ vivid patterns or images, far more accurately than they could conjure from imagination. If no one’s told you to expect this when you lose your sight, this can of course be alarming. I’m fascinated to learn from the book that deaf people sometimes experience an equivalent form of auditory hallucination.
It’s also common for people to experience hallucinations as they drift into sleep, or as they wake. Hallucinations tend to be exacerbated by tiredness and stress, and can even be brought on by a dearth of sensory stimuli (e.g. pilots flying in clear, lonely skies have to be aware that if they go a long while without a break, their brain may begin to invent something to break up the monotony). Research participants who submitted themselves to sensory deprivation for a number of days would, without exception, begin to see vivid images over which they didn’t seem to have control (but nor were the images frightening - most thought they were amusing or annoying).
So, even without seeking out drugs to experiment with hallucinations, or being remotely unwell either mentally or physically, it is quite common to have hallucinations of one kind or another. For some of us, it might be a once in the lifetime, one of a kind experience. Others hallucinate daily and have woven it into their lives.
How helpful would it be, though, if we might be able to name it and talk about it? Sacks emphasises that most hallucinations are easily identified by the person experiencing them and usually they are not frightening or distressing. But sometimes hallucinations might at the very least startle you, or they might be something pretty challenging to live with. Being able to explore the experience and its meaning, not to mention its impact on you, strikes me as a very fruitful area for therapeutic work as well as an excellent topic of conversation between friends and families.
I want my clients to feel that they can share any part of their experience with me. As a mental health professional, I know they might see me as someone who could rush them off to the nearest psychiatrist at the first whiff of something hallucinatory. This book has certainly extended my thinking about how to meet the hallucinatory experience of my clients (as well as how to think about my own) and I do believe that, unless your hallucinations are causing you the kind of distress that interferes with your life, you probably don’t need medical help. But being able to explore your experience in an environment that feels safe and accepting, with someone who is not going to assume you are “mad”, could be really valuable.