Tag Archives: Hyperconnectivity

Memory is fallible, but then again, there’s super-recognizers

It appears that super-recognizers (people with very good face recognition ability) are mentioned in the new book The Memory Illusion by Dr Julia Shaw, but I cannot find a preview of that bit of text. I’d be interested in reading what Shaw wrote about supers, because I believe that we are very good evidence against the argument that this book, and some other pop psychology books have offered, that human memory is unreliable and open to interference. I’ve noticed that writing by researchers and authors who offer arguments against the reliability of human memory (such as Elizabeth Loftus) and also those who offer arguments against the idea of natural or inborn talent (such as K. Anders Ericssson) tend to ignore or gloss over the many things that science already knows about face recognition, face memory and super-recognizers.

I’m happy to admit that people who perform amazing feats of semantic memory such as remembering huge lists of random facts or meaningless digits using new or ancient memory techniques have trained their own memories with many hours of practice, but super-recognizers are very different to those people. We do not knowingly or deliberately train ourselves and we do not consciously use tricks or techniques. Maybe we self-train and invent strategies in an implicit manner, but it is also true that super-recognition does seem to run in families, so there seems to be an important genetic contribution to the elite ability or talent, just as there is clearly a genetic component to developmental prospagnosia (very poor face recognition ability).

Face memory researchers have been investigating the phenomenon of super-recognition since it was first described in 2009, and there seems to be ample evidence that supers have very long-lasting, adaptable, and reliable memory of the faces of other humans. We can remember faces across many decades and across changes in facial appearance by forces such as ageing. I believe I am very good at spotting facial family resemblance and facial phenotypes across gender and age. Super-recognizers can also display very accurate face recognition after being briefly shown images of only faces (no hair etc) of a large group of faces of same gender and similar age, some of them very degraded images. This accuracy requires being able to avoid false positives and false negatives. There’s no denying that supers are bloody good at faces. There’s also no denying that some other people are very poor at face memory, so authors of these pop psychology books that denigrate human memory are able to state with a vague air of truth that human memory for faces is fallible. But such a statement ignores what we know about supers, and this is why I have issues with the common practice of psychology researchers of roputinely discarding data from outliers in their studies. If any of that discarded data is from outlier study participants that did incredible well in tests of face recognition or memory, then those participants could be supers and their data tells an important story about human memory and human face recognition.

I think supers are interesting examples of a type of human memory that stands out from other types of human memory as reliable, long-lasting, easily or unconsciously enmcoded and accurate, so one should wonder, why is the face memory of supers so great? My bet is that this niche example of human memory has two characteristics that give it special power: it is disributed across a broad network of neurons throughout the brain (and this is why it might be found along-side synaesthesia), and it is also a type of visual memory, which I can only assume is a very ancient and well-evolved type of human memory that predates stuff like writing and language, that happens in areas of the brain that work amazingly and unconsciously because they evloved well before there ever were humans. I cannot imagine how genuine face memory could ever be interfered with by suggestion or manipulation, because the tricks that some memory researchers have used to fool around with the memories of study participants work on a conscious level communicated by verbal means. Genuine face memory is implicit and visual. It is safe from such nonsense.

The Memory Illusion by Dr Julia Shaw:

https://books.google.com.au/books?id=OdKOCwAAQBAJ&source=gbs_navlinks_s

 

Dr Kevin Mitchell explains how genetics works with learning in the development of synaesthesia

My blog has two main themes, and one of them is exploring the relationship between super-recognition and synaesthesia. This theme was the main point of the very first posting in this blog, a description of an unusual experience of mine, which opened up a wonderful journey of exploring undiscovered relationships between interesting concepts in neuroscience, psychology and immunology. In my blog I have also asserted that there’s a reason why both synaesthesia and special abilities in reading and literacy-based skills seem to run in my family tree.

If you were wondering how the brain-based characteristics of super-recognition, synaesthesia, precocious reading and superior ability in reading and writing might be connected, I recommend that you have a read of this blog posting from Dr Kevin Mitchell, a researcher in developmental neurogenetics based in Ireland.

Mitchell, Kevin Schema formation in synaesthesia. Wiring the Brain. (blog) May 10th 2016.

http://www.wiringthebrain.com/2016/05/schema-formation-in-synaesthesia.html

 

All those years of neuroimaging research on the brains of synaesthetes has found nothing of substance?

Hupé J and Dojat M (2015) A critical review of the neuroimaging literature on synesthesia. Frontiers in Human Neuroscience. 9:103.
doi:10.3389/fnhum.2015.00103

http://journal.frontiersin.org/article/10.3389/fnhum.2015.00103/abstract

“Our critical review therefore casts some doubts on whether any neural correlate of the synesthetic experience has been established yet”

That is a bit of a shock to read. This isn’t the first time that I’ve gotten a big shock after reading a paper in the journal Frontiers in Human Neuroscience. There was that little matter of some of my most amazing neuroscientific ideas published at this blog being ripped-off and used as the guts of an “opinion article” in that journal in 2013. I haven’t forgotten that episode. Who would have thought so much excitement is there to be found inside a science journal? I should make it clear that the researchers who did that thing in 2013 are NOT the authors of the above paper, but at the same time, I’ve got to wonder where Hupé and Dojat got this idea from

“…synesthesia could be reconsidered as a special kind of childhood memory, …”

Sure, they could have thought of that under their own steam, but I still want to point out that the central, seminal idea of this blog, right from the very first post in 2010, has been the idea that synaesthesia is linked in some meaningful way with face memory, in my case with super-recognizer ability in face memory, and there are many articles in this blog that show and hint that the heart of synaesthesia is memories created in childhood and many different types of synaesthesia operate in ways that are so much like memory that the differences are only quantitative. There was even one article published in 2013 at this blog in which I stated that

“…the Proust phenomenon is considered to be a type of memory and many of my observations at this blog have demonstrated that synaesthesia can involve memory, is an element of the “method of loci” memory technique and I would argue operates like memory. Yes, Yes, Yes, the Proust Phenomenon is a close relative of synaesthesia.”

Some ideas that I’d like to (explicitly) lay claim to (right now) in 2014

Another fascinating addition to the Mindscapes series

Mindscapes is a series of articles by Helen Thomson at New Scientist magazine on neuro-psychological topics that often overlap with the kinds of things that I write about here. The latest in the series is an article about Sharon whose condition is developmental topographical disorientation (DTD). For a long time I’ve included within this blog’s large and useful link list a link to a useful researchers’ website about this type of disability or problem because it appears to coincide with prosopagnosia in some people, and extreme variation in face memory ability is one of the main themes of this blog. That researcher’s website is Getting Lost.ca and it is run by people at the NeuroLab which is directed by Dr. Giuseppe Iaria and is located in the Department of Psychology of the University of Calgary. Sharon in this article was diagnosed by Dr Iaria.

Without knowing it, I have already written about the type of experience that Sharon feels when she becomes geographically disoriented (but this is possibly a piece of writing I never published). On the odd occasion I’ve had similar experiences while riding trains in low light conditions or on unfamiliar train lines. For a moment or two I will struggle to make sense of where I am in relation to Perth’s geography, nothing will feel familiar and will feel as though I might have mistakenly got on a train heading in the wrong direction. There is no sensory alteration associated with this kind of brief experience, just the loss of a sense of certainty and a feeling of familiarity. My theory is that this experience is caused by two different systems in the brain (visual and spatial) which both contribute towards navigation going out of sync, disconnecting or one operating in  the absence of the other. I believe the basic problem is a loss of a sense of the four directions, or in my case, more specifically a loss of the sense of where the sea is (west). Nothing in navigation makes sense if you don’t know the directions, which is why maps all have a north-pointing arrow (should point west in my opinion). I think Dr Iaria’s team’s  idea of a therapy using a belt with tactile stimulation to indicate north is a great idea, but they might want to consider if some “patients” might find some other direction more personally and emotionally  meaningful.

I think it is interesting that the researchers have found that people who experience DTD have “decreased communication between two brain areas”. You could call this hypoconnectivity, and this fact fits in neatly with the well-supported theory that prosopagnosia is characterized by hypoconnectivity. At this blog I have put forward the theory that super-recognition, which is elite ability in face memory and the opposite of prosopagnosia, is the result of hyperconnectivity, a theory that is supported by the fact that I’m a super-recognizer and I also experience many different varieties of synaesthesia, a harmless neuro-cognitive variation which a number of research studies have found to be associated with hyperconnectivity. At this blog I have also theorized that there are clusters of interesting neuro-cognitive conditions that could be seen as opposites because they are either characterized by high ability and hyperconnectivity or impaired ability and hypoconnectivity. In the “hyper” camp I place super-recognition, synaesthesia, precocious reading, a heightened visual and spatial sense of place (manifest by walking, outdoor photography and creating navigational computer simulations as favoured pastimes) and giftedness in literacy skills such as reading, spelling and writing (which runs in my family which has included a number of specialist English teachers, a librarian and a university student of literature). In the “hypo” camp I’d place DTD, dyslexia and poor reading fluency and prosopagnosia. My scheme of clusters raises a couple of interesting questions. Is there a condition that is the opposite of synaesthesia? How would it manifest in experiences or behaviour? Might it manifest as an inability to comprehend metaphorical speech or thinking, such as the statements “I’d like to try a sharp cheese” or “What a cheeky little car the Volkswagen Beetle was”. Might it manifest as a lived experience in which colours are not a big thing or a huge pleasure or a distraction? Might it manifest as a calm and logical disposition in which ideas are only thrown together after fully conscious and logical consideration? We must always take into consideration that synaesthesia appears to be a stable and ubiquitous feature of the human race, but synaesthetes are always naturally a minority group. If it is so fantastic being hyperconnected, with good reading skills and top face memory, why hasn’t evolution selected this trait for all or most of humanity? This brings us to the second question that follows from my cluster theory. If a group of disabilities is characterized by hypoconnectivity, and being a “hypo” runs in families (as it does), then why does nature keep giving us “hypo” people? My intuition about evolution and bell curves tells me that there must be either a negative side to being a “hyper” or a positive side to being a “hypo”. Being average and normal must have a lot going for it too I guess. Do “hypo” people have some special gift? Are they good at sport or perhaps unusually calm or focused? Some people believe dyslexia in some way promotes entrepreneurial ability, citing names like Sir Richard Branson and Kerry Packer as examples. More research needed!

An afterthought; synaesthete readers – do you have colours for the four directions? Are they based on the colours of the first letters of the names of the directions, or are they unique colours? Do you experience images for any of the directions?

Backs up my ideas

I was reading through back issues of New Scientist, and I found a brief article about the work of researcher Sophie Scott and other researchers, written by Simon Makin. This article is about one theory of dyslexia winning out over another. The theory that seems to be the most compatible with recent research findings is the theory of dyslexia as a “disconnection syndrome” resulting from poor connections between particular regions in the brain. The competing theory of dyslexia as a disability stemming from subtle problems with hearing speech sounds is apparently being debunked.

What relevance does this have for my theories and ideas about synaesthesia and visual perception? The theory of dyslexia as a problem of hypoconnectivity in the brain is not new, but it is nice to see it winning favour among researchers because it fits well with observations that I made years ago at this blog that there seems to be a cluster of phenomena linked to grapheme-colour synaesthesia in my family, and some of those phenomena are exceptional gifts in specific areas of literacy, including spelling, writing and reading, identified by professional and independent testing for selective school entry, as well as precocious reading and one case of superior face memory (a super-recognizer). A few years ago at this blog I contrasted this combination of literacy and visual memory gifts found along with synaesthesia (a sensory-perception phenomenon that researchers have found is caused by greater than average connectivity in the brain) with what I have argued is the opposite condition of a type of dementia named Benson’s syndrome which has loss of ability to read, spell and recognize faces as symptoms of atrophy at the back of the brain, the general area of the brain that I theorized is hyper-developed or hyper-connected in some members of my family, including myself. Although dyslexia isn’t the same thing as Benson’s I think the evidence about dyslexia fits in nicely with my ideas. If a reading disability is caused by hypoconnectivity in the brain, that does seem to support my idea that reading superiority can be caused by the same difference that makes a brain a synaesthete brain, that difference being hyperconnectivity. The hypoconnected dyslexic looks like the opposite of the hyperconnected synaesthete who has always been ahead of his or her peers in reading and writing, and perhaps even taught him or herself to read before grade one.

Some ideas that I’d like to (explicitly) lay claim to (right now) in 2014

A note of warning – If you are thinking about copying or plagiarizing any of the text, ideas or descriptions in this post or using it in your own work without giving me (C. Wright, author of the blog “Am I a Super-recognizer?”) the proper acknowledgement and citations, then think again. If you do that you will be found out and my objection will be well publicized. If you believe that you published any of these ideas before I did, please let me know the details in a comment on this article. If you want to make reference to this blog post or any of the ideas in it make sure that you state in your work exactly where you first read about these ideas. If you wish to quote any text from this post be sure to cite this post at this blog properly. There are many established citation methods. If you quote or make reference to material in this blog in your work, it would be a common courtesy to let me know about your work (I’m interested!) in a comment on any of the posts in this blog. Thank you.

The idea that Benson’s syndrome or posterior cortical atrophy or PCA, a variety of dementia, is caused or develops in a way that can be seen as the opposite of the synaesthesia linked with exceptional visual memory and literacy skills that runs in my family (this idea has been explored previously in this blog).

The idea that the above cited states develop or are caused in a way that makes them seem like opposites because they both affect the same or similar areas of the brain, but in opposite ways.

The idea that the above described process happens because Benson’s syndrome and our variety of synaesthesia are both mediated by the same or similar natural chemical or cells or biological agent in the brain, one caused by high levels of the mystery substance and the other caused by low levels (a hypothesis that I briefly suggested in January 2011).

The idea that one of the many known or unknown elements of the immune system that impact brain development is the mystery substance referred to above (a hypothesis that I briefly outlined in 2012).

The (implied in above ideas) idea of the immune hypothesis of synaesthesia. (This idea was first published by me in 2012 in a blog post archived here, was I believe plagiarized in 2013 here, and was the subject of my plagiarism claim here.)

The idea that one or more of the complement immune chemicals is the  mystery substance referred to above.

The idea that the C3 complement immune chemical  is the  mystery substance referred to above.

The idea that synaesthesia is linked with one or maybe more immune diseases or conditions caused by low levels of complement.

The idea that genes for synaesthesia stay quite common in the gene pool because of some associated cognitive advantage (probably superior memory) that balances out any disadvantages caused by deficiencies in the immune system.

The idea that some or many people unintentionally experience a memory process that operates in a similar way to the method of loci memory technique in their everyday lives, unintentionally forming long-term associations between individual learned concepts and individual visual memories of scenes (I have named this phenomenon Involuntary Method of Loci Memorization or IMLM).

The idea that IMLM operates in such a similar way to synaesthesia that one could argue that it is a type of synaesthesia.

The idea that synaesthetes are more likely to experience IMLM than non-synaesthetes.

The (implied) idea that the method of loci memory technique is similar to or a type of synaesthesia.

The idea that synaesthetes might have a natural advantage in using the method of loci because the method of loci is similar to or is a type of  synaesthesia. This idea that seems likely in light of the case of “S” the Russian memory performer with many types of synaesthesia described by Luria. 

The idea that IMLM is a phenomenon that is caused by enhanced synaptic plasticity throughout the life span.

The idea that IMLM is a phenomenon that is caused by enhanced synaptic plasticity throughout the life span and can thus be used as an indicator of which synaesthetes are synaesthetes due to enhanced synaptic plasticity throughout the life span rather than other possible causes of synaesthesia. Support for this idea comes from the fact that IMLM appears to be a non-developmental variety of synaesthesia that can form new long-term associations in adolescence and adulthood.

The idea that IMLM is a phenomenon that is caused by the unusual possession of levels of synaptic plasticity typical of a young child, during adolescence or adulthood.

The idea that IMLM is caused or enhanced by some characteristic of the immune system that affects the functioning of the brain. Many different elements of the incredibly complex immune system are thought to affect the functioning or development of the brain, and could thus be involved in IMLM, including the complement system, microglia and the MHC class I molecules. Researchers such as Beth Stevens and Carla Shatz have investigated this exciting area of neuroscience. In 2012 I hypothesized at this blog that synaesthesia could be caused by low levels of complement, this idea implying that the immune system is directly involved in synaesthesia (or at least some cases of synaesthesia). I believe these ideas were plagiarized in a paper published in 2013.

The idea that IMLM is similar to the “Proust phenomenon” in that it is very similar to synaesthesia or is a type of synaesthesia and involves episodic or autobiographical memory as a concurrent.

The idea that phonics as a foundational reading skill is similar to or is arguably a type of synaesthesia in that it involves the involuntary association of individual speech sounds with individual printed letters or combinations of letters, as the result of learning in early to mid childhood.

The idea that at least one type of dyslexia is like a deficiency of synaesthesia.

The implied idea that if synaesthesia has as it’s basis hyperconnectivity in the white matter of the brain, dyslexia as an opposite of synaesthesia or a deficiency of synaesthesia is or could be caused by hypoconnectivity in the white matter of the brain (I suspect there might be existing research evidence that supports this idea).

The implied idea that in at least one cluster or grouping of cases synaesthesia is associated with superiority in literacy or reading skill.

The idea that synaesthesia can happen in different regions of the brain, and because of this the experience of various types of synaesthesia can vary in detectable ways because of the influence on the synaesthesia of the varied ways that different areas of the brain operate. This can mean that one synaesthete can experience different types of synaesthesia that operate in very different ways, for example, some types of synaesthesia more rare or spontaneous or intrusive than other types. (I am not completely sure of the originality or the novelty of all of this idea.)

The idea that there is an association between synaesthesia and super-recognition that is not merely coincidental.

The idea that synaesthesia is a type of memory or learning. (Not sure if I’m the first to note this obvious fact).

The idea that synaesthesia concurrents are re-experienced memories, or re-activated “learnings” of concepts, not perceptions. (Not sure if I’m the first to note this obvious fact). In support of this idea I can assert that synaesthesia is like face recognition in that both are visual memory-based phenomena which are subject to the Verbal Overshadowing Effect or something very similar. My assertion that synaesthesia is subject to the verbal overshadowing effect is based on my own observations (outlined elsewhere in this post).

The idea that super-recognizers should or could be trained and employed as expert consultants in the practice of medical genetics.

The idea that medical geneticists and all types of medical specialists need to have a super-recognizer level of face memory or face recognition ability, so that they can intuitively and quickly recognize medical facies.

The idea that there is no clear point of distinction between medical facies or faces associated with genetic syndromes and normal faces.

The idea that super-recognizers could be used to facially identify blood relatives of a person or persons.

The idea that super-recognizers could be used to facially identify the specific ethnicity of a person.

(below ideas added January 28th 2014)

The idea that super-recognition or being a super-recognizer could develop as the result of an unusual level of fascination with the visual appearance of landscapes or scenes, rather than from a fascination with faces, and thus be a side-effect hyper-development of a part of the brain that serves two similar functions.

The idea that super-recognition or being a super-recognizer could, at least  in some cases, develop as the result of a general hyper-development of the visual sense to compensate for problems in the auditory sense during childhood such as temporary deafness, recurrent ear infections, glue ear or poor auditory processing.

(below idea added February 1st 2014)

The idea that lexical-gustatory synaesthesia is an exaggerated form of some kind of evolutionary adaptation in the brain that biologically primes the mind to attend to or react to speech on the subject of food (this idea was discussed at this blog in a post dated January 27th 2011, with more consideration in a later post).

(below ideas added February 6th 2014)

The idea that creativity might be immediately enhanced during and only during the duration of physical or visual-spatial activity because the activity activates areas of the brain associated with movement and in turn these areas activate other areas of the brain including those that give rise to conceptual thinking, and the increased activation makes novel associations between diverse thoughts and concepts more likely, and that this process is like synaesthesia or is a type of synaesthesia, and the types of physical activity that are the most effective inducers of this effect might be highly specific, highly specific in effects, highly varied between individuals and highly idiosyncratic, as is typical of synaesthesia inducers and concurrents. Driving a car can act as an inducer of this effect. (I have gone some way to exploring this idea in past posts.)

The idea that mental flexibility might be immediately enhanced by the above effect, which I will name “movement – thought-flexibility synaesthesia”.

The idea that thinking might be immediately enhanced by the above effect.

The idea that memory might be immediately enhanced by the above effect.

The idea that the above effect is similar to embodied cognition or is a type of embodied cognition.

(below ideas added February 14th  and  February 20th 2014)

The idea that synaesthesia is like the process of face recognition (and vice versa), because they both

– are subject to the verbal overshadowing effect or something similar

– are automatic

– are involuntary

– have a sensory inducer, in face recognition always visual, in synaesthesia I think most frequently visual

– have or can have a concurrent that could be described as a memory, a concept or a personality (I’m comparing face recognition with personification synaesthesias and the synaesthesias that I have described at this blog which have visual memories of scenes as concurrents)

– are or can be visual in both the inducer and concurrent

– typically involve the fusiform gyrus

– involve set pairings of inducers and concurrents (same person’s face seen before then recognized later)

– involve set parings of highly specific inducers and concurrents (I recognize that an employee at my local supermarket has a sister who has just started working there too, as their faces and bodies and hair are near-identical, but for the extra acne and the more receding chin of the new employee. They are very similar in appearance but my discrimination is highly specific, just as I can recognize that the green wall on the lower floor of a public library is close to but not quite the same colour as Tuesday.)

– both can have, but do not always have an actual face as an inducer (we can recognize the faces of celebrities in photos, caricatures and art, even seeing Marilyn Monroe’s face in a pattern of brown coffee cups stuck to the wall at the coffee shop at the art gallery.)

(below idea added February 17th 2014)

“My particular interest in personification is my own theory that personification synaesthesia (as experienced by myself) or something like it gives rise to superiority in face memory (or being a super-recognizer) by naturally making the faces of unknown people more memorable and interesting”

The above is a quote from an article that was published at the blog in October 2013.

(below ideas added February 19th 2014)

The idea that the synaesthesia brain is the result of the developmental influence or shaping from, or the adaptation to, the behavioural phenomenon of “flow” as described by Mihaly Csikszentmihalyi.

The idea that synaesthesia, intellectual giftedness or high IQ and autism or Asperger syndrome seem to coincide more often than chance because gifted and autistic kids are more likely to experience “flow” and this in turn can influence the developing brain in a way that gives rise to synaesthesia.

(below ideas added February 20th 2014)

The idea that the genuine conscious awareness of synaesthesia is a threshold phenomenon that operates in conflict or competition with conscious thinking, meaning that consciously thinking about synaesthesia can inferfere with the perception of concurrents, and synaesthesia must reach a particular level of intensity before it interrupts the experience of consciousness and becomes itself the subject of conscious awareness. I think that the idea that thinking about synaesthesia can interfere with the perception of synaesthesia might be related to the “verbal overshadowing” effect which has been described and debated about by researchers. In fairness I should point out that Mark C. Price speculated in the recently published (2013) Oxford Handbook of Synesthesia that synaesthesia could be subject to the verbal overshadowing effect. My own ideas were arrived upon independently from Price’s writing or work.  I base the ideas of synaesthesia being a threshold phenomenon which can also be interfered with by conscious thinking on a number of my own observations. In direct contradiction to what I had expected to find, my scores for accuracy for individual letters and numbers in The Synesthesia Battery (a scientifically-validated online test of synaesthesia) were lower for the numbers and letters that have colours that I find beautiful and which I have thought about to some degree, while my best accuracy was for the numbers and letters that have the dull and ugly colours. It seems the less I think about the concurrents the more accurately I can percieve them when they are evoked. I have also noticed that most of the types of synaesthesia that I experience I was not consciously aware of before I started to think about and examine the idea of synaesthesia. I never realised that I had complete stability in the colours I associate with months and days of the week till I tested myself. While I had a dim awareness of colour colouring my thoughts, I’d not realised that this worked like synaesthesia till I went looking for a pattern using simple testing. My fine motor movement-visual memories of scenes synaesthesia evokes concurrents that are so fleetingly and subtly experienced that they just feel like random thoughts, and indeed I now believe it is possible that the random thoughts of many or even all people are in fact synaesthesia of various types. I have also observed that there are some very unsubtle and intrusive types of syn that I experience, and they are typically rarely experienced and are associated with people, emotions, faces, singing voices or music that I find striking or novel as inducers. Because of the circumstances of these examples of synaesthesia, I think some kind of threshold is being breached when these types of synaesthesia are experienced by me.

The idea that one of the established defining criteria for synaesthesia, that it gives rise to perceptions or concurrents which are “consistent and generic (i.e., simple rather than pictorial)”, is wrong, and specific categories of memories of complex visual images such as faces and scenes, which are processed in the fusiform gyrus, can also be experienced as genuine synaesthesia concurrents. I base this assertion on the fact that I often involuntarily experience synesthesia concurrents of this type, and I have written about such experiences right from the first post in this blog which was published in 2010. I have also named types of synesthesia that have complex visual memories as concurrents: the strange phenomenon, fine motor task – visual place memory synaesthesia, involuntary method of loci memorization, etc. There are also many accounts or scientific observations of synaesthesia with complex visual concurrents in the scientific literature on synaesthesia.

Prevalence rates of some interesting neurological conditions and disorders

Number form synaesthesia   ~12% (Ward, Sagiv & Butterworth 2009)

Dyslexia   5-10% English-speakers (Mitchell Feb 2011)

Dyscalculia   5-6% (Mitchell Feb 2011)

Congenital amusia (tone deafness)   4% (Mitchell Jan 2011) (Mitchell Feb 2011)

Day of the week -> colour synaesthesia   2.8% (Banissy et al 2009)

Prosopagnosia   1-2% (Mitchell Feb 2011)

Congenital prosopagnosia 2.5% (Mitchell Jan 2100) (This figure is inconsistent with the above figure as people with congenital prosopagnosia should be a sub-set of all people who have prosopagnosia)

Mirror-touch synaesthesia   1.6% (Banissy et al 2009)

Grapheme -> colour synaesthesia   1.4% (Banissy et al 2009)

ASD including autism   ~0.6% (Wikipedia)

So this means that, if the disorders besides autism listed above do not overlap in the people they affect, possibly almost a quarter of the population either can’t read, can’t do maths, can’t comprehend music normally, or can’t recognize faces adequately, while diagnosable autism is thought to only be found in less than a percent of people. So why so much hysteria and research funding about autism and so little funding for research into all the other issues?

The total number of synaesthetes in the population cannot be calculated by simply adding up the different types of synaesthesia listed above, because we know that individual synaesthetes often have a number of different types. Regardless, it is clear that synaesthetes make up a sizeable proportion of the population, and synaesthesia isn’t rare at all. So why is it that most teachers that I have spoken to have never heard of synaesthesia, a neurological condition (not disorder) that can directly affect learning (positively and on occassion negatively) and can affect the student’s sensory experience in the classroom?

References

Banissy, Michael J, Kadosh, Roi Cohen, Maus, Gerrit W, Walsh, Vincent, Ward, Jamie Prevalence, characteristics and a neurocognitive model of mirror-touch synaesthesia. Experimental Brain Research. (2009) 198:261–272. Published online: 3 May 2009. DOI 10.1007/s00221-009-1810-9 http://www.springerlink.com/content/26mh37152110617x/fulltext.pdf

Mitchell, Kevin The Neuroscience of Tone Deafness: The strange connection between people who can’t sing a tune and people who are “face blind”. Scientific American. January 18th 2011. http://www.scientificamerican.com/article.cfm?id=the-neuroscience-of-tone

Mitchell, K. J. Curiouser and curiouser: genetic disorders of cortical specialization.Current Opinion in Genetics & Development. 2011 Feb 4. [Epub ahead of print] http://www.ncbi.nlm.nih.gov/pubmed/21296568

Ward, Jamie, Sagiv, Noam and Butterworth, Brian The impact of visuo-spatial number forms on simple arithmetic. Cortex. Volume 45 Issue 10 Pages 1261-1265 (November 2009). http://www.cortexjournal.net/article/S0010-9452(09)00213-5/abstract

New journal paper appears to contrast prosopagnosia with synaesthesia

I’d love to read this new journal paper. It is by the same author from an Irish university who wrote a recent article in Scientific American magazine that I recently mentioned in this blog. Synesthesia (a familial developmental neurological condition) is contrasted with familial developmental disorders such as dyslexia, dyscalculia, prosopagnosia, color agnosia and amusia.

Curiouser and curiouser: genetic disorders of cortical specialization.

Mitchell KJ.

Current Opinion in Genetics and Development. 2011 Feb 4. [Epub ahead of print]

http://www.ncbi.nlm.nih.gov/pubmed/21296568?dopt=Abstract

Link between face recognition and synaesthesia becoming obvious – interesting new article about tone-deafness and prosopagnosia in Scientific American magazine

This interesting recent article explains the many similarities between tone-deafness and face-blindness, and how both conditions can be caused by “structural disconnection” rather than damage to the specific parts of the brain that “do” face recognition or musical perception. The distinction between the developmental and congenital forms of these conditions are explained.

You don’t need to be a genius to see that the “structural disconnection” discussed in this article could be seen as the opposite of synaesthesia, but just in case that isn’t completely obvious, synaesthesia is mentioned at the very end of the article, in the notes about the author of this article, who is a scientist at Trinity College in Ireland who studies “the genes involved in wiring the brain and their possible involvement in psychiatric disorders and perceptual conditions, including synaesthesia.” Indeed!

A word of caution – I don’t think there is anything in this article that says that prosopagnosics are more likely to be tone-deaf, or vice versa. Although it would seem a sensible assumption that a group of traits should be found together: good face recognition should be found with intact or great or maybe even excellent ability to consciously comprehend musical notes (perfect pitch or absolute pitch), should be found with synaesthesia, but this is not always the case. Apparently there are synaesthetes who are also very poor at face recognition, and the synaesthete author Vladimir Nabokov has been reported by Oliver Sacks to have possibly had “a profound amusia” (Sacks 2007, 2008 p. 109-110), based on a passage that Nabokov wrote in his memoir Speak, Memory. I think amusia is a fancy word for tone-deafness. In the book Musicophilia Oliver Sacks describes a number of different types of amusia, and interestingly, this prosopangnosic author also describes in his book some episodes of  amusia that he experienced which were a part of the aura of his  migraine headaches. There are so many connections here that it’s almost like looking at a plate of spaghetti!

Are people who have perfect pitch better than average at face recognition? Are super-recognizers synaesthetes? Is perfect pitch unusually common in synaesthetes? Are the opposite deficits associated with each other? Get to work, researchers!

Mitchell, Kevin The Neuroscience of Tone Deafness: The strange connection between people who can’t sing a tune and people who are “face blind”. Scientific American. January 18th 2011. http://www.scientificamerican.com/article.cfm?id=the-neuroscience-of-tone

Mitchell, K. J. Curiouser and curiouser: genetic disorders of cortical specialization.Current Opinion in Genetics & Development. 2011 Feb 4. [Epub ahead of print] http://www.ncbi.nlm.nih.gov/pubmed/21296568

Sacks, Oliver Musicophilia: tales of music and the brain. Revised and expanded edition. Picador, 2007, 2008.

Tranel, D. Damasio, A. R. Knowledge without awareness: an autonomic index of facial recognition by prosopagnosics. Science. 1985 Jun 21;228(4706):1453-4. http://www.sciencemag.org/content/228/4706/1453.abstract  http://www.ncbi.nlm.nih.gov/pubmed/4012303

 

Postscript 2013 – I’ve had comments from at least one person who is apparently a definite and high-profile super-recognizer to the effect that she is not a synaesthete, so that’s a strike against the idea that supers are synaesthetes. Regardless, I reserve the right to point out that some researchers have found that some study subjects who claim to not have synaesthesia have returned test results that suggest that they are, so it appears to be possible to be a synaesthete and not know it.