Tag Archives: Synesthesia

British former police detective and writer also a super-recognizer?

“I’ve been told I have a photographic memory. I’m not sure that such a condition exists, but it is true that I never needed to refer to my notebook in court, made interviews a nightmare for suspects and could not forget a face, crime or clue. Badge numbers, car registrations, court cases, names and faces are all stored neatly on my mind’s infinite box of index cards and I usually have little trouble recovering them when needed.”

This passage on page 12 brings to mind the famous memory genius discovered by the Russian neuro-psychologist Alexander Luria, the synaesthete newspaper reporter whose memory gift was discovered by his boss after he explained why he never needed to take notes in a notebook. Luria gave him the name of S in the book that he wrote about the case; Mind of a Mnemonist. A couple of questions also come to mind on reading the above passage. Is it true? Who can tell? The author of the passage, which is an excerpt from the beginning of the book The Crime Factory, goes by the anonymous pen-name of Officer A, so checking the truth or probability of these quite extraordinary claims would have to be difficult. Another question – if Officer A’s memory really is as amazing as claimed, did it get that way by a natural gift or by training or a combination of both? One final question – is Officer A a synaesthete like the amazing S? I’ll have to continue reading to see whether any of my questions are answered. One thing that I can say about the book is that the bit about treating a case of severe bleeding in the leg utterly contradicts what I was taught in St John Ambulance first aid classes, so I think there is at least some dodgy information in the book.

I’ve found more interesting stuff on page 53. in which the author explains the pros and cons of having a “photographic memory”, and it it clear that it can cause a condition that is perhaps related to post-traumatic stress disorder in which ordinary visual stimuli can “trigger” the involuntary retrieval of visual memories of unpleasant scenes experienced in his work as a police officer. An example given is the sight of a stainless steel draining board triggering a visual memory of a dead baby after a post-mortem examination. I think I’ve written on the subject of PTSD before when reviewing the book The Shaking Woman by synesthete novelist Siri Hustvedt, and I recall that I speculated that PTSD might be connected to PTSD. After reading this book I’m all the more convinced, because the involuntary recall of traumatic visual memories described by the policeman seems to operate in the same way as synaesthesia, and is in many ways similar to my many experiences of having non-traumatic visual memories of scenes or faces evoked by visual or other cognitive triggers, which I have argued are a less-known types of synaesthesia. I’m not the least surprised that an extraordinary visual memory can have great advantages and disadvantages.

Don’t let me mislead you into thinking this is a book about neuro-psychology. It is basically an action-packed autobiography of a British detective who has worked in England and also in Perth, Western Australia. Western Australian readers will no doubt be shocked by the ugly picture that the anonymous author has painted of the police in Perth.

Amazon UK page for the book  http://www.amazon.co.uk/Crime-Factory-Shocking-Front-Line-Detective/dp/1780575254

Sunday Times (WA) article by Anthony DeCeglie about the book and accusations made in it about WA police  http://www.perthnow.com.au/news/western-australia/cop-spills-all-on-wa-police/story-e6frg13u-1226532858410

Cached text-only version of quite shocking April 2012 article from People magazine by Douglas Wight that is based on the book’s introduction  http://webcache.googleusercontent.com/search?q=cache:http://www.people.co.uk/news/uk-world-news/2012/04/15/the-filth-explosive-revelations-of-police-officers-crimes-hushed-up-to-save-embarrassment-102039-23825713/&hl=en&tbo=d&strip=1

Some unusual types of synaesthesia which I have experienced only rarely or during a limited period in my life

Coloured flavour / Coloured smell synaesthesia / taste – colour synaesthesia

Most taste experiences are an amalgam of taste sensation on the tongue and smell sensations in the nose, so to be completely correct this isn’t purely triggered by a taste, smell is certainly an element, but in plain-language terms, the trigger is a novel taste or flavour.

This only happens during the unusual situation in which I am at a public swimming pool or some other place where I have the smell of chlorine in my nose and I am also drinking iced coffee, and there is some kind of chemical reaction between the chlorine and the coffee in my mouth/nose resulting in a peculiar smell/taste that is somewhat like a floral or perfume smell. It is a black-coloured smell/taste. Sometimes the image of a black-coloured flower flashes into my mind, shaped something like a simple lily. Upon reflection I believe that it is the surprise or novelty of the modification of the usual flavour of iced coffee that is the synaesthesia trigger or inducer. Often as an afterthought after this experience I realise that the normal taste of iced coffee is a brown-coloured taste, but I never notice this as it is such an ordinary thing that it kind of stays below the level of consciousness.

Viewed facial expression – flavour synaesthesia

It is hard to know for sure what the exact trigger was. It was only ever triggered by one person when they were preschooler-aged, giving me one of those big hugs that parents get when they pick a young child up at the end of a kindy day, the kind of hug that has a run-up with open arms, involving an incredibly cute young child wearing a huge smile, not your average hug situation at all. What was the exact trigger? The emotion? The situation? The hug? The child? The time in our lives? I think it was the image of that incredibly cute individual young child’s face with a big smile on it, but I’m not really sure. I have a number of kids. This experience only ever happened in relation to one child, and I believe this is because of facial appearance. The period in time when this used to happen was many years before I had ever heard about the concept of synaesthesia, and I had no idea why I was experiencing a pleasant phantom taste in my mouth in this type of situation, and I thought it was most odd, but also rather nice. Sometimes this very rare experience included a kind of other-worldly feeling, like a very short visit to a rather nice alternative reality. It has been many years since I had this experience and I don’t expect I will ever experience it again. Why do children have to grow up?

The Strange Phenomenon or image of one person’s face evoked by viewing another’s face in a synaesthesia process

Described in great detail here: https://superrecognizer.wordpress.com/2010/12/04/a-most-peculiar-experience/

Smell/taste – concept synaesthesia

Two different pleasant and specific sensory experiences have triggered the same subtle and rather vague conceptual experience. I’m not completely sure what the synaesthesia trigger (inducer) and the synaesthesia anomalous experience (concurrent) are. It’s a vague and subtle and quite mysterious thing. A couple of years ago I started drinking tea more than I had been in the past. It was Twinings tea, because that was the only brand on the market offering a range of different types of teas, genuine old tea varieties made from different types of tea leaves from different countries, not the modern ridiculous teas with synthetic fruity flavouring added. I had been drinking some of the more popular tea varieties like the breakfast teas and Orange Pekoe, and then I tried out Prince of Wales tea, which is a black tea with a quite different and a much more refined and subtle taste. For a short period of time, perhaps a few weeks, my first sip of Prince of Wales tea would reliably trigger an idea that would spontaneously jump into my head, a strange nostalgic feeling that is hard to describe. The  image and the smell of old, pale-coloured paper notes of currency (which is hard to identify) would come to mind, along with ideas of my maternal grandmother, the fine, old French perfume that she wore, finely scented old varieties of roses (which might have once grown in her now-demolished rose garden), an old saying that she used to use “I wouldn’t trade you for all the tea in China”, notions of fine things from the Orient in the “olden days”, the concept of exotic delicacies from foreign lands, and a generally nostalgic feeling of having visited a better world for just a small moment.

Upon reflection, I think this very specific variety of tea (Twinings Russian Caravan tea has a very similar taste to the Prince of Wales variety but does not act as a trigger for my synaesthesia) is not the only sensory experience that has triggered this weird nostalgic sensation/concept. Many years ago on a beautiful day I was testing the scents of different varieties of roses at a specialist plant nursery, and I recall that the subtle but beautiful smell of the Buff Beauty variety of rose, a pale yellow-pink hybrid musk rose that was bred in 1939, was unusually evocative, triggering thoughts of pale old paper bank notes and a peculiar sense of nostalgia that seemed to extend beyond my own years on Earth. This interesting experience was not enough to sway my purchasing decision, and I ended up buying a similar variety of hybrid musk rose which had a stronger smell and a prettier colour, but with fairly limited powers of evoking conceptual thinking.

It appears that sadly this is another type of rare synaesthesia which I will never be able to experience again, because a few years ago something changed.  My first sip of Prince of Wales tea no long packs a beautifully subtle punch. It no longer evokes anything but a tea flavour. Perhaps the trigger of the strange experience had actually been the contrast between the taste of this type of tea and the more full-flavoured varieties of tea that I had become accustomed to back then. The trigger might have been the novelty of the new taste of a more refined tea, but I’ve got to wonder why I experienced no synaesthesia triggered by drinking a full-flavoured tea after drinking Prince of Wales for a while. I’m inclined to think that the quality of the Prince of Wales variety of Twinings tea dropped off or changed, causing the end of the odd phenomenon. I’ve tried countless other varieties of tea to see if they evoke that odd experience to no avail, and even though boutique tea shops are popping up all over Perth stocking all manner of horrible brews, none of them carry any Prince of Wales variety tea. I give up! I just give up!

Touch – emotion synaesthesia

When I was a teenager I had the habit of wearing a favourite item of clothing almost non-stop till it fell apart. I guess that as a result of this practice, by brain built up a substantial touch-memory of how my favourite garments felt when I wore them, an unusual type of memory which I possibly don’t possess these days and which most people never possess.  Back in those days I found that something weird would happen when I was in the change room of a department store or boutique trying on new clothes. As I put on the new garment I would feel a spontaneous, involuntary, unexpected, weird, sudden, dramatic wave of something like a hybrid of an emotion and a bodily sensation. It was something like a shudder. Even the emotion itself was hybrid-like and hard to describe, perhaps dread, perhaps intense homesickness, maybe it was a sense of adventure, or maybe loneliness. Weird! At the time I assumed that this thing happened because it violated my unconscious expectation of the familiar touch-memory of my old, well-worn clothes. As is often the case with types of synaesthesia that I rarely experience, sensory novelty or change appears to be the real trigger or the synaesthesia inducer. I’m not sure how often or for what period of time I would have this odd experience while trying on new clothes, but I am sure it was limited to my teenage and possibly early adult years. It is no longer experienced, presumably because I no longer in the habit of wearing a favourite items of clothing constantly, or conceivably it could be because I have less sensitive senses these days.

Time-blind, face-blind, smell-impaired, touch-disabled, dyslexic – there’s an amazing variety of disabilities of perception

It goes to show how common synaesthesia is, when a host of a radio show episode about super-recognition that I have referred to previously at this blog just happens to be a synaesthete. I know this because she was on the radio yesterday morning promoting her latest pop psychology book, which looks like it will be an interesting read. The BBC broadcaster, author and psychologist Claudia Hammond experiences the days of the week as having their own colours and insists that Monday is a pillar-box red, an assertion which to my mind does not seem odd but simply incorrect. Sure enough, the letter M is red (but certainly not pillar-box red) but surely it is plain to anyone that Mondays are white? Hammond and the cheery radio show host Natasha Mitchell also discussed other varieties of synaesthesia: time-space synaesthesia and mental number lines. Hammond’s new book is about the perception of time and it looks like it will include discussion of disability in perceiving time, and will also probably cover time-space synaesthesia.

I’ve had a look on the internet for more info about Hammond’s new book titled Time Warped, and while reading an excerpt of the book at Amazon I’ve found yet another obscure and highly specialized type of disability of perception, an inability to sense the passing of time, a condition which appears to be so obscure that it still has no name. Hammond gives a fascinating description of Eleanor, who has a deficit in sensing the passing of time that goes way beyond poor time management skills, and also has dyslexia, probably not coincidentally.

In this blog which is primarily about exploring possible links between synaesthesia and high ability in face perception and also an exploration of the opposite condition of prosopagnosia or face-blindness, I have discovered that prosopagnosia is by no means the only highly specialized disability of perception. Prosopagnosia is only one of a range of visual agnosias, which is a sub-set of the agnosias, which are a huge range of brain-based diabilities (not associated with memory loss) in recognizing specific things such as people, voices, shapes, smells, time, faces, colours, classes of objects, images of objects, pain, speech, text, body language, intonation, etc. Prosopagnosia appears to be often associated with another agnosia which is a disability in establishing visual memories of scenes, including things like streetscapes and buildings, and it seems possible that it could be linked with other better-known disabilities such as dyslexia. Each case is different, and prosopagnosia and other agnosias can be caused by genetics or damage in the brain, so one should not make sweeping generalizations. There appears to be no standard term or definition of the issue with place memory, with a variety of terms in use. I guess most people would be aware of the sensory and perception disabilities of blindness, deafness, paralysis and dyslexia, but there is also a huge range of other specific disabilities and disorders of perception and understanding, some affecting taste, smell, balance, mathematical and number sense, touch, music and tone perception. Many of these can be naturally-occuring or the result of brain injury. New Scientist magazine reported a while ago that a deficit in the sense of touch appears to be genetically linked with deafness. Scientists are only now beginning to establish knowledge about the nature of these disabilities and possible relationships between them. On top of this bewildering range of agnosias and disabilities are sensory disorders and visual disturbances that can be asociated with mental illness or are similar to mental illness. And on top of that are sensory-cognitive experiences that are simply odd or unusual but not disordered or a deficit. Synaesthesia fits into this category, of which there are more types than any sensible person would claim to know.

I find these things endlessly fascinating because it gives an insight into the significant fact that there can be many important differences between the way that apparently normal, intelligent people percieve and understand what appear to be simple sensory inputs from the world around us. The more I study this subject, the more I understand that there is nothing simple about perception and the understanding of sensory inputs. This kind of brain-work is hugely complex and it is no wonder that many areas of the brain are involved in this kind of work, and that sensory processing is very much involved in thinking in general. It is impossible to guess how many different ways that the person sitting next to you on the train might differ from you in perception and sensing, and it isn’t only about disability. For many of the agnosias and diabilities of perception and sensing there are conditions that are opposites or give rise to superior abilities that are like opposites. Does the old bloke across the way see violet mauve in his mind’s eye when he hears the train driver sound her horn, because the horn is at a pitch that his mind links with this colour, in an interaction between his perfect pitch and his coloured sound synesthesia? Does the super-recognizer in the carriage feel a tingle of familiarity from looking at two of the faces in the carriage? Is the super-taster still recovering from the second-rate coffee that he paid too much for at a fancy cafe? Is one passenger watching the screen display of info about which station the train is at like a hawk, instead of using her spare time to catch up on some reading, because she was born without any sense of time passing and can’t remotely judge the duration of her planned train journey?

Time warped: changing your perception of time. Life Matters. Radio National. July 2 2012. http://www.abc.net.au/radionational/programs/lifematters/claudia-hammond/4100994

I wish I knew Spanish

This is a Google translation of the publicity blurb of a new Spanish book about synaesthesia:
“What if the words have color? Normally, we see the colors, smell the smells, hear the sounds, taste the flavors and feel sorry only the things we touch. But this is not always true, newborns experience the sensations coming from the different senses mixed together, as happens to people and adults who experience the phenomenon of synaesthetic perception. When a person perceives synesthetic sensory stimuli, such as listening to a musical note, the note is heard not only more or less acute but also have taste or color. You may know fresh watermelon, or you can see green lemon. Others are synesthetic each letter of a particular color but are written in black, or perceive each number, or days of the week, or month of the year, arranged in front of them at a particular location in space. Why are experiencing these feelings? Can it be avoided? Do they affect other facets of life? Are we all a little synesthetes? Scientific research is uncovering the secrets of synesthesia to answer these questions, and also lead to a radical rethinking of how our senses are organized and how the brain allows us to interpret the complex world we live and unfold it.”

It sounds interesting. Pity I don’t know the language.

Sinestesia: El color de las palabras, el sabor de la música, el lugar del tiempo…

Alicia Callejas (Autor/a), Juan Lupiáñez (Autor/a)
Colección: Alianza Ensayo



Sinetisia – Facultad de Psicología – Universidad de Granada http://ncog.ath.cx/~danics/index.html

Magnet by Bombay Bicycle Club

I wouldn’t know about this piece of pop music if we didn’t have any teenager in our family. I don’t know a thing about this band, except that they are probably young and talented. When I heard the sound of this tune floating out of one of the bedrooms of our house I wondered if it might be Tame Impala. This tune struck me as a bit psychedelic because of the colour in the chorus, with its wooo wooo wooo style of singing, which is the kind of thing that you might find in the chorus of a psychedelic song. The colour is a pleasant light mauve-grey, rather like the colour that is currently in the background of this blog.


Coloured Flavour / Smell Synaesthesia or Taste to Colour Synaesthesia – a type that I only experience occasionally

Most taste experiences are an amalgam of taste sensation on the tongue and smell sensations in the nose, so to be completely correct this isn’t purely triggered by a taste, smell is certainly an element, but in plain-language terms, the trigger is a novel taste or flavour.

This only happens during the unusual situation in which I am at a public swimming pool or some other place where I have the smell of chlorine in my nose and I am also drinking iced coffee, and there is some kind of chemical reaction between the chlorine and the coffee in my mouth/nose resulting in a peculiar smell/taste that is somewhat like a floral or perfumey smell. It is a black-coloured smell/taste. Sometimes the image of a black-coloured flower flashes into my mind, shaped something like a simple lily. Upon reflection I believe that it is the surprise or novelty of the modification of the usual flavour of iced coffee that is the synaesthesia trigger or inducer. Often as an afterthought after this experience I realise that the normal taste of iced coffee is a brown-coloured taste, but I never notice this as it is such an ordinary thing that it kind of stays below the level of consciousness.

Rarely experienced types of synaesthesia – I’ve noticed some interesting patterns

Inspired by reading the fascinating fairly new journal paper by Spanish researchers comparing some more rare types of synesthesia with auras in mysticism, I have been playing with the idea of writing a post in which I list all of the types of synaesthesia that I have ever experienced, the common and the rare, and then I started writing down all of the rare types that I’ve only ever had happen a few times or even only once. I noticed something interesting about these types – out of a total of eight that I’ve thought of, three of them appear to be triggered by the novelty of a sensory or linguistic experience, and all other five types have some aspect of a person or persons as the “inducer” or trigger. So my rarely experienced types of synaesthesia appear to have completely different categories of triggers as my more frequent or ordinary synaesthesia experiences, which can be triggered by learned concepts such as years or numbers, or can be triggered by movement (manual chores) or music or purely sensory experiences like smell or voices. There seem to be two really quite distinct classes of synaesthesia types, the rare sporadic types triggered by persons or novelty, and the common frequent types triggered by the types of sensory and conceptual stimuli that researchers have already fully explored and described, at least in the way that my mind works. Why?

Other cases of synaesthesia involving face perception – I’m certainly not the only one

“In short, for our person–colour synaesthetes the inducer can be sensorial, semantic or a motor one: An emotion, an action, an attitude, facial recognition or sense of familiarity. Then we can speak of synaesthesia, ideaesthesia (Nikolic, 2009) and kinetoesthesia.”

That is a quote from a very interesting paper by Spanish psychology researchers that was published in the journal Consciousness and Cognition in March of this year. So we have a case of synaesthesia involving facial recognition described in a science journal. So I’m not the only one in the world. I never thought I was the only one, in fact I think I might have predicted that other cases must exist, somewhere in this blog, based on the observation that functions of the fusiform gyrus are so often involved in the various types of synesthesia (colour perception, letter recognition, word recognition) and face recognition is another function of the fusiform gyrus. I have given a special name to my own experience of facial recognition synaesthesia – “The Strange Phenomenon”, and I described it in great detail in the very first post in this blog. This blog was created as a record of my search to find a scientific explanation for The Strange Phenomenon. The authors of the March 2012 paper also found action-related synaesthesia, which is another unusual type of synaesthesia that I experience which I have also described in detail in this blog. I often experience images in my mind’s eye of sometimes very old memories of landscape scenes from my past triggered by doing fine-motor household chores with my hands.

The question needs to be asked – why have Spanish researchers been able to discover and describe such interesting and complex cases of synaesthesia, while there don’t seem to be comparable case studies from the UK or the US? I’ve never seen people -> animal synaesthesia described or even mentioned as a possibility before reading the fascinating paper that was published in March in the journal Consciousness and Cognition. Perhaps the apparently negative attitude of V. S. Ramachandran towards synaesthete subjects of study gives a clue as to why more interesting synaesthesia case studies seem to be missing from research from English-speaking countries. The famous Rama’s habit of describing synesthesia as a scrambling of the brain grates the first time one reads it and gets very, very old once I’ve seen it in print a few times. On the other hand, perhaps there is nothing wrong with Anglophone synaesthesia researchers, and it is simply the case that the Spanish have more interesting minds, including Spanish synaesthetes. Having viewed paintings by Dali and photos of buildings by Gaudi and witnessed a strikingly original and often quite dangerous performance by La Fura Dels Baus at the Perth International Arts Festival a couple of years ago, I could believe that.

E.G. Milán, O. Iborra, M. Hochel, M.A. Rodríguez Artacho, L.C. Delgado-Pastor, E. Salazar, A. González-Hernández Auras in mysticism and synaesthesia: A comparison. Consciousness and Cognition.  Volume 21 Issue 1, March 2012, Pages 258–268. http://www.sciencedirect.com/science/article/pii/S1053810011002868  (This paper is clearly a translation and difficult reading in parts)

Synesthesia May Explain Healers Claims of Seeing People’s ‘Aura’. ScienceDaily. May 4th 2012http://www.sciencedaily.com/releases/2012/05/120504110024.htm

Ramachandran VS, Miller L, Livingstone MS, Brang D. Colored halos around faces and emotion-evoked colors: A new form of synesthesia. Neurocase. Available online: 25 Nov 2011.  DOI:10.1080/13554794.2011.608366. http://www.tandfonline.com/doi/abs/10.1080/13554794.2011.608366   http://psy2.ucsd.edu/~dbrang/images/Ramachandran_NNCS_InPress.pdf

Ramachandran VS The Tell-Tale Brain: A Neuroscientist’s Quest for What Makes Us Human. W. W. Norton & Company, 2011http://www.amazon.com/The-Tell-Tale-Brain-Neuroscientists-Quest/dp/0393077829  http://books.google.com.au/books/about/The_Tell_Tale_Brain.html?id=Y5vLDglww74C&redir_esc=y (Robert with coloured face aura synaesthesia indicating emotions percieved in others and also diagnosed with Asperger syndrome described on pages 101-102.)

Thomson, Helen Is this proof that spooky auras are real? Short Sharp Science (blog at New Scientist) 14 November 2010. http://www.stumbleupon.com/su/34lNK2/www.newscientist.com/blogs/shortsharpscience/2010/11/auras.html?utm_source=KurzweilAI+Daily+Newsletter&utm_campaign=0ab5dd44ff-UA-946742-1&utm_medium=email/r:t

Are the flashbacks that are an element of Post-Traumatic Stress Disorder a troublesome variety of synaesthesia and/or related to the Tetris effect?

I’m going to explain why I think this question is worth considering.

I have recently been reading a most interesting book that has been descibed as a “medical memoir”. I have read that the fiction writer Siri Hustvedt has mirror-touch synaesthesia, and I was rather interested in reading about that, but the main topic of Hustvedt’s book The Shaking Woman is her search for an explanation for her seizure-like shaking episodes that are triggered by public speaking.

One thing that I’ve noted is that both Siri and her late father have experienced PTSD-type flashbacks of traumatic memories (warfare, car accident). Like myself, Siri Hustvedt has also experienced the Tetris effect, which is like PTSD flashbacks in that it is an involuntary experience of a visual memory. I don’t experience the Tetris effect much these days, but when I do it is typically in response to a full day of weeding or some other outdoor repetitive work. I don’t think scientists know how common the Tetris effect is, and if it is a thing that everyone experiences then it wouldn’t mean a thing that the novelist and I both experience it. I have at least one other close blood relative who has also experienced the Tetris effect quite a few times. The Tetris effect operates through an unknown memory system, possibly related to procedural memory, according to the Wikipedia. I would think that the Tetris effect would have some type of visual memory system as its basis. It is interesting that Hustvedt’s mysterious shaking episodes were dampened-down but not completely cured by the drug propranolol, which (according to the book) is also used to treat high blood pressure, migraine, performance anxiety and PTSD. Hustvedt seems to have a lot of whatever mechanism is the basis of PTSD, which I guess might be a very strong or hyperconnected visual memory system in her brain. I would think this system is also probably responsible for the Tetris effect. Another reason to believe that the Tetris effect and PTSD operate in the same brain system is that a study described in the Wikipedia found that playing a Tetris-like video game soon after a traumatic event “….reduces the number of flashbacks that are experienced afterwards”. I guess a specific memory system becomes overloaded with memories if the game is used as preventative treatment, so less of the traumatic memories can be encoded properly for long-term storage.

Hustvedt and I have quite a few things in common. We are both synaesthetes, we have both experienced the Tetris effect, we have also both experienced and migraine headaches, and we have both apparently had brain-based experiences of involuntarily-retrieved visual memories. In her book Hustvedt did not spell out explicitly that her flashbacks included visual content, and she did mention the memory of sound, but I’m happy to assume that anything labelled as a “flashback” included visual content. My involuntarily-retrieved visual memories are two different types of synaesthesia which I’ve experienced which trigger visual memories of scenes or a face. Hustvedt’s shaking episodes are like synaesthesia in that they have a very specific trigger (public speaking) and a very specific manifestation (violent body tremors without apparent anxiety, or under the influence of propranolol, an “electric buzz” quiver throughout the body).

There seem to be a lot of things here that are inter-connected. My experiences of my fine-motor->visual memories of scenes synaesthesia and The Strange Phenomenon, which is I believe a hybrid of face recognition and synaesthesia in which seeing one face under very specific conditions triggers an involuntary experience of a very old memory of the face of another person, show that synaesthesia concurrents or triggered additional sensory experiences can be in some ways similar to PTSD flashbacks, but without any accompanying psychological distress. My fine-motor-triggered visual memories are very subtle and hardly noticeable, while the face memory evoked in The Strange Phenomenon is more of an intrusion into ordinary consciousness. I’d like to put forward the theory that the flashbacks of PTSD (and not any of the other distressing features of PTSD) are synaesthesia concurrents that just happen to be distressing visual or sensory memories. I guess they must have some type of trigger, and I guess could be something purely sensory, very subtle or ordinary. I have never experienced PTSD myself, probably because I have fortunately never been in the type of extremely traumatic situation that causes this psychological syndrome, so I can only guess at what PTSD flashbacks are really like from what I’ve read. Are PTSD flashbacks the result of a type of synaesthesia that can manifest as quite a subtle experience, but are only troublesome or exceptional because of the very unpleasant nature of the memories evoked? Are synaesthetes more likely to develop PTSD if exposed to trauma than non-synaesthetes exposed to equivalent situations? It’s just a theory!

Wikipedia contributors Tetris effect. Wikipedia, The Free Encyclopedia. http://en.wikipedia.org/w/index.php?title=Tetris_effect&oldid=448999724

The Shaking Woman. The Book Show. Radio National. April 22 2010.  http://www.abc.net.au/rn/bookshow/stories/2010/2878610.htm

Synaesthesia has got to be involved with this

“Hair on a G string”
letter by Tim Benzie, London, UK
New Scientist. August 10th 2011
Magazine issue 2825.