There’s a Cave Bear Close Behind Me and It’s Treading on My Tale: Were Prehistoric Painters Hallucinating?

fang

The photograph above shows a cave bear tooth that I’ve had it for years and keep by my bedside, as a sort of talisman I suppose, but also as a link to the past and the world in which our ancestors lived. The coin by its side is a more modern Roman denarius, about 1 cm across. This bear had a formidable bite.

I’ve always been interested, like most people, in prehistoric cave dwellers and in the art they left behind. So I pricked up my ears when I heard Oliver Sacks suggest that some cave art could have been partially inspired by visual impairment.

In case you don’t know, Sacks is a neurologist and writer of a series of best-selling books. His idea came as a throw-away remark at the end of his TED talk on Charles Bonnet Syndrome.

Charles Bonnet syndrome (CBS) is something experienced by many people who lose some or all of their vision. They see vivid hallucinations involving a phantasmagorical range of objects. These may be “formed” – look like physical objects, such as animals or landscapes – or “unformed”, which means they consist of geometric objects, patterns, symbols and the like. If you don’t know about CBS already, Sack’s talk is well worth listening to.

The conjecture that these visions may have some connection with cave art is a daring and intriguing thought. I wondered if I could find any evidence to support it. Obviously we cannot now ask the artists and the only approach is to compare their legacy with pictures known to have been drawn by CBS sufferers.

In the cave art of Europe byte most noticeable motif is animals of various kinds, such as this famous horse from the cave of Lascaux (image from Wikipedia).

LascauxHorse

It seems hard to interpret images such as these as pictures of CBS hallucinations. This horse looks like something the artist is familiar with in everyday life and the simplest explanation is surely that they have painted a portrait of something they know.

Unformed – geometric – pictures seem more promising candidates. These non-representational images are very common hallucinations amongst CBS sufferers. They are thought to originate in specific parts of the visual system, dedicated to recognition of shape and geometrical forms. These pathways can’t have changed greatly in the last 40 000 years. And in cave art geometry is commoner than animal images by a factor of two to one, although it attract less notice.

For comparison I turned to the excellent and comprehensive study by Genevieve von Petzinger, who has surveyed geometric cave art from many parts of the world and classified the signs she found there. Here is my sketch of the 8 commonest she identified.

cave art around world

She named these 1. Circle 2. Dots 3. Triangle 4.  Quadrangle 5. Piniform (=Featherlike) 6. Angle 7. Line 8. Oval

What about present-day pictures drawn by CBS sufferers, showing the hallucinations they have witnessed? These are surprisingly rare and perhaps this is related to the fact that CBS is under-reported. I think people don’t want to admit they are “seeing things” because they fear stigma.

To my considerable surprise I was unable to do better than the pictures I myself drew when suffering from CBS. I thought thee might be many hits but found very few. So here is one of my sketches.

BlogPic1

My names for these were:

A the Hexagons

B me jumping into a vortex

C the Pennants

D the Gingerbread Man

E the Bubbles

F Triangles

G the Chequered Tablecloth

H the Scroll

I Benzene Rings

J  Herrings and Undulations

K the Hand

What strikes me straight away is that these don’t look much at all like the geometric cave art.

I felt quite persuaded at the start of the investigation that I would see close and compelling parallels between cave art and CBS hallucinations, but disappointing perhaps the evidence turns out quite weak.

So perhaps the images of CBS are not so much like cave art after all.

But this made me wonder if there are other forms of art that are more like CBS? If so could the similarities result from similar neurological conditions? I shall explore this idea further in my next post.

Advertisements

About partialinsight

One evening I had a stroke. Half my sight vanished overnight. Adapting made me grasp how amazing the visual system and brain are. It also taught me to understand disability completely differently and I'm grateful for the lesson.
This entry was posted in Art and vision, Blindness and visual impairment, The brain and visual perception and tagged , , , , , , , , , , , , . Bookmark the permalink.

4 Responses to There’s a Cave Bear Close Behind Me and It’s Treading on My Tale: Were Prehistoric Painters Hallucinating?

  1. Steve says:

    I had a minor stroke a couple of years ago and as a result have lost my left field peripheral vision. In the ‘early days’ after the stroke (maybe during the first week) I experienced what sound like CBS-style hallucinations (of people and animals). At the time I didn’t know I’d had a stroke (I’d just been discharged after major surgery and was stuffed full of various meds and (although it may sound strange) I didn’t actually realise I’d lost my sight) … so the hallucinations were a bit of a shock! Subsequently, a bit of reading round the subject suggested that hallucinations aren’t uncommon with brain injuries affecting the visual areas, but I hadn’t come across CBS. Time for some Google searches I think …

  2. I don’t think it’s strange at all to not notice vision loss, I think it will be common.

    It’s very interesting to hear about the people and animals. What did you see, can you recall? I saw every few minutes a group of alsatians, or a group of human runners (legs and feet only, sort of Chariots of Fire-ish), and always going from right to left,

    It used to be thought until about 1990 that CBS was very rare. Now it seems that it or something similar is experienced by – probably most people who lose a significant part of their sight, for whatever reason. There is almost always under-reporting I suspect.

    Why:

    — Stigma is the usual explanation and seems very likely. There are reported differences of prevalence between ethnicities, but these could be cultural, probably are: could neurology be so different between groups of people all of whom are genetically almost identical?

    — Not knowing how to describe the experience. I found it hard, there are some things I saw that I am still struggling to express in a way that would make sense to anyone else.

    — It’s hard to mention it to a health care professional, because there is little time, they are busy, they set the agenda, they ask you questions, other things seem more pressing…

    I saw at least 1 GP, 1 neurologist, 1 vision counsellor while I was experiencing CBS and said nothing. Only when I had a one-hour appointment with the low vision clinic just a couple of weeks back did I come out with it – I saw hallucinations! And the people I was talking to knew about CBS all right, we had a good conversation and they clearly thought the variety of what I saw was very interesting and quite unusual. But it probably isn’t, we just don’t know enough or collect enough patients stories.

    Thanks for the post, I’m trying to raise awareness of CBS and this sort of dicussion really helps me clarify my thoughts!

  3. Steve says:

    Ah yes, the stigma! That’s a bit of a hurdle isn’t it! Although you can rationalise it and tell yourself it’s not happening you do fear that, were you to share it with someone else, they may think that you’re reaching your sell-by date …
    As regards the hallucinations themselves, mine were shortlived but a bit un-nerving!
    Nothing really outlandish – I could easily describe what I experienced – one time it was a 1/4 size version (!) of my daughter coming to see me and jumping up to sit next to me (coincidently on my ‘blind’ side) when I was recuperating from my earlier operation and sitting up in bed – the other was small animals (I think they were cats – which have had, but not at the time in question) running round the room.
    The reasons for delay in reporting vision loss in general may be many and varied – as well as the potential stigma associated with discussing CBS events I was convinced that my own loss of vision (which I only became aware of after a couple of days) was due to the ‘mother of all migraines’, that it would return once the migraine trigger was removed, and that it was not something that had sinister cause. I have always been sensitive to flickering fluorescent lighting and the intensive care unit I was on post-op seemed particularly bad. My vision loss associated with migraines has (more often than not) been the ‘inverse’ of HH – where I lost central vision but retained peripheral. My experiences post-op seemed different but at the time I couldn’t understand ‘how’ they were different (or at first that they were happening at all). Recovering from the deep anaesthesia associated with cardio-thoracic surgery and the impact of a cerebral stroke would obviously leave some potential for cognitive impairment and I think this was a major symptom at the time (and one that was missed by medical staff – although not my wife!). I have since concluded that it was only after a few days ‘recovery’ that I was able to identify and begin to understand what I was experiencing – although it was still a few more days before I organised a trip to the GP (where I did discuss the hallucinations quite openly). This put into action a chain of events that led to an immediate referral and CT scan, confirmation of a stroke and (another) stay in the local hospital. Hurrah. Not sure how much my GP considered the hallucinations as a symptom – I’ll try to remember to ask her when I next see her and will report back.
    Regards – Steve

  4. I was convinced at first that I was “only” having a super-migraine. Painless migraines have happened me now and again for years and this was at first quite similar. It was only when I saw that not only did I have jagged flickering disruption of my vision but actually couldn’t see anything at all on my right side that I became alarmed.

    24 hours later it seemed pretty sure it had been a stroke (probably *was* still a stroke) and I started to see stuff, starting at first with “strobes” – if I moved my hand (or somebody else moved anything) in the visual region where the visual problem seemed to be, I saw multiple slow-motion and smaller copies of it in stroboscopic time-lapse.

    This sounds a bit like your 1/4 size daughter, only it was “formed” – I was seeing what was really there, but in a fragmented and distorted way. It’s different from the “unformed” visual disturbances, such as the alsatians I saw, purely imaginary.

    There’s a lot of other things too. Please keep writing!

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s