Synesthesia, some people perceive individual symbols, characters, numbers

In summary: If you do, then you are in the top 25% based on my estimate and reading. I have a theory that EVERYONE has synesthesia, but most don't recognize it. For example, when you think about a door knob, do you feel anything in your hand?In summary, the conversation discusses synesthesia, a condition in which individuals perceive individual symbols, characters, numbers, and letters as having their own color. It can also involve a mixing of senses, such as seeing letters as colors. The conversation includes personal experiences with synesthesia, famous people who have claimed to experience it, and a recommendation for further reading on the subject. The possibility of synesthesia being more
  • #71


http://www.1watchmovie.com/the-real-superhumans-discovery-channel/"

Amazing video including a woman synestheste who has combined color, taste, sound, and a man who blind from birth paints by sense of touch, including brain study conducted at Harvard University showing his visual areas activated as he paints, and a man who becomes a sudden savant with amazing mathematical ability, and Ray Kurzweil who seeks immortality by taking steps to live long enough (has family history of heart disease among other things) to become a benefactor of breakthroughs in gene/stem cell research, and a man who controls his body temperature and attempts to run a 1/2 marathon in subzero temperatures in only shorts, and no shoes.

One more thing, when they performed a simple memory test (recall 15 items on a list) on the woman with synesthesia she got 9 right after being read the list. The interview went on for over an hour and then unannounced came back to the same test. This time she got 14 of the 15 right. Somehow in that period her mind had stored that information, even thought the first time she couldn't recall them. Pretty remarkable.

Rhody...
 
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  • #72


rhody said:
zooby,

After a second look, at 7:15 in his presentation, Cytowic states, about 1 in 23 people have some form of synesthesia, and that the most common kind is sensing days of the week as color. At 12:00 he says, about 1 in 10 people have the number form without synesthesia, and you have synesthesia you have about a 60% chance of having a number form. I am a bit confused as well, because about a minute before he was introducing the number form describing it with a visual, further qualifying it as spatial sequence synesthesia, because what numbers, calendars, shoe sizes, temperatures, etc... are is that they are all over learned sequences. Listen to these two segments carefully and see if your interpretation is what I reported above.
I look at it this way, the section from 11 to 12 minutes is complex, linked and detailed, maybe critical focus was lost and he did not fully clarify what he intended to say.
I finally watched this yesterday and I agree that he failed, for some reason, to clearly lay out this whole "number form" thing. He implies that a "number form" is related to, but is not exactly, synesthesia. "Number form", though, from the context, seems to be short for "the number form of synesthesia". He has, after all, thrown it in amongst discussions of forms of synesthesia. Yet, having a "number form" seems merely to mean someone has an externally located and positioned association with numbers with no sensory hallucination. I can't tell for sure. It's very confusing.
 
  • #73


zoobyshoe said:
I finally watched this yesterday and I agree that he failed, for some reason, to clearly lay out this whole "number form" thing. He implies that a "number form" is related to, but is not exactly, synesthesia. "Number form", though, from the context, seems to be short for "the number form of synesthesia". He has, after all, thrown it in amongst discussions of forms of synesthesia. Yet, having a "number form" seems merely to mean someone has an externally located and positioned association with numbers with no sensory hallucination. I can't tell for sure. It's very confusing.

zooby,

I agree. I came to the same conclusion as you. No one is perfect, even when speaking in public. That being said, after I post my summary of the last 1/2 of the book, I am almost done reading it. I have a nagging question, in rare cases people have what is known as bi-directional synesthesia, which I take to mean, sound sensation -> color sensation -> taste sensation -> sound sensation ? which may occur in many forms due to the combinations possible when mixing two or more of the five senses.

I will try to do some research on my own and include any clarifying information that I dig up. Right now I am led to believe that anyone who has bi-directional synesthesia leads a quiet secluded life for obvious reasons with sensation overload and annoying repeating feedback.

Rhody...
 
  • #74


Just found this: http://home.comcast.net/~sean.day/html/types.htm" from over 1090 people participating.

Also: from the same link:

Dr Cytowic now has plenty of company doing research as well.

Note: Dr Ramachandran who wrote Phantoms in the Brain, for me that launched this little learning adventure last winter.

Feel free to probe and contribute if you wish.

Up to date list of researchers and their published articles/research, profiles/pictures on this page, quite nice...

2cs79k4.jpg


Rhody...
 
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  • #75


rhody said:
zooby,
I have a nagging question, in rare cases people have what is known as bi-directional synesthesia, which I take to mean, sound sensation -> color sensation -> taste sensation -> sound sensation ? which may occur in many forms due to the combinations possible when mixing two or more of the five senses.
From the videos alone, no further research, I understood bi-directional synesthesia to involve only two senses. Let's take taste and touch. In the case of bi-directional synesthesia a person would have their sense of touch activated by tasting food, and would also have their sense of taste activated by touching things. So, eating a pizza would cause then to feel as if they're touching a particular kind of surface, form, or material. Likewise, touching a piece of wood, for example, would cause them to feel they're tasting a particular substance in their mouth. So, this scenario goes through my mind: at the same time they're tasting the pizza and having some feeling of touch triggered, touching the pizza would trigger a conflicting taste in their mouth. Depending on the senses involved you could imagine it might be hellish, and this bi-directionality of two senses alone could cause the kind of sensory overload that would lead them to sequester themselves.

The other thing, multi-modal synesthesia, wasn't completely clear to me from the videos. I had the impression that the many modes were always triggered by stimulation of the same initial sense. Sound might trigger taste and a color display. But it wouldn't be bi-directional. Initially tasting something wouldn't also trigger the other two, and the initial sight of a splash of colors wouldn't trigger the other two. There would be a dedicated triggering sense that had to be stimulated to cause the rest to activate.

There is a review-like compactness to his remarks that sometimes ends up being cryptic. He only alludes to things that probably should be more thoroughly explained. Maybe he's assuming familiarity with his new book.
 
  • #76


Ben Niehoff said:
I also have letter-color synaesthesia. The colors are typically very specific shades, and sometimes they seem to have other qualities such as shininess or translucence. Someone earlier mentioned that A tends to be red, B blue, and C yellow. However, for me, A is a reddish orange, B is light blue, C is pale yellow. E is bright, cherry red.
Ben, does reversing the background have any effect? Are white letters on black any different?

Here's a page of Blackle (the energy saving google) where the letters and numerals are all white on black background:

http://www.google.com/cse?cx=013269018370076798483:gg7jrrhpsy4&cof=FORID:1&q=synesthesia&sa=Search

Same question for waht and daughter of evo.
 
  • #77


zoobyshoe said:
Ben, does reversing the background have any effect? Are white letters on black any different?

Here's a page of Blackle (the energy saving google) where the letters and numerals are all white on black background:

http://www.google.com/cse?cx=013269018370076798483:gg7jrrhpsy4&cof=FORID:1&q=synesthesia&sa=Search

Same question for waht and daughter of evo.

zooby, what, and Evo, via Evo child,

I just read zooby's question, and looking down the author/publication list a few posts ago, I found this: http://home.comcast.net/~sean.day/Dixonetal2005.pdf" .

After you read the first paragraph or two, a simple question, does the sensation of color letters appear on the page, or projected into external space, according to Dr Dixon, projection only occurs in about 10% of people with the sensation in colors and letters ?

From quickly scanning the conclusions I think they are trying to determine if those with color letter synesthesia have better comprehension, recognition, etc... in processing the information than those who don't have it.

Rhody...
 
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  • #78


zoobyshoe said:
Ben, does reversing the background have any effect? Are white letters on black any different?

Here's a page of Blackle (the energy saving google) where the letters and numerals are all white on black background:

http://www.google.com/cse?cx=013269018370076798483:gg7jrrhpsy4&cof=FORID:1&q=synesthesia&sa=Search

Same question for waht and daughter of evo.

That's interesting. I'll try to do my best to describe it. The black background and white/gray letters are sort of uncomfortable, but the visual letter to color association is still there. When I close my eyes, and mentally think of a letter or say it outloud, I also experience a sense of color. When I changed font color to green, and keep background black, I would say it's harder to get a color experience just from visual input. What happened was I looked at a green letter "A" for example, and sort of have to think of an "A" and then get a color experience similarly as if I had my eyes closed and thought about it.

Interestingly, when I changed to a white background, and keeping font green, I get a direct letter to color experience rather quickly.

So I'm not really sure what's going on exactly, the differences are subtle. I would say though that there is a time delay that varies from the point of looking at the letter to getting a synesthesia color "kick" and it subtly varies from different combinations of font and background colors.
 
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  • #79


rhody said:
After you read the first paragraph or two, a simple question, does the sensation of color letters appear on the page, or projected into external space, according to Dr Dixon, projection only occurs in about 10% of people with the sensation in colors and letters ?

After reading those paragraphs, I'd say definitely that there is no external projections going on, it's more of an internal thing. Although I do have a biased urge to say that letters should have those synesthesia generated colors. So if "A" conjures up images of yellow, I also feel that it should be yellow.
 
  • #80


I wanted to re-read Man Who Tasted Shapes but the one copy in the library system here was on hold.

I found out both Amazon and Ebay have many paperback copies available for, like, a dollar (plus shipping).

https://www.amazon.com/gp/product/0446670685/?tag=pfamazon01-20

I ordered one, and am already halfway through my re-reading. It's very much more interesting than I remembered. I think anyone who's been following this thread won't be disappointed if they spring the five or so bucks for a copy ($1.00 for the book, $4.00 for the shipping, I paid.)
 
  • #81


zoobyshoe said:
I wanted to re-read Man Who Tasted Shapes but the one copy in the library system here was on hold.

I found out both Amazon and Ebay have many paperback copies available for, like, a dollar (plus shipping).

https://www.amazon.com/gp/product/0446670685/?tag=pfamazon01-20

I ordered one, and am already halfway through my re-reading. It's very much more interesting than I remembered. I think anyone who's been following this thread won't be disappointed if they spring the five or so bucks for a copy ($1.00 for the book, $4.00 for the shipping, I paid.)

zooby,

If you finish the first half of the book, take a quick peek at my post #34, and feel free to add anything that struck you. I am almost finished with the book, and plan to post the rest of my insights here soon, I will copy the list from post #34 and include the last half in one place for ease of reading. I just looked at Cytowic's personal site and plan to buy, "The Neurological Side of Neuropsychology" next and report back on it. Like I said awhile ago, I think this thread has plenty of life (because of my interest) in it. HeHe. This is a general comment, I can't believe with the fairly large membership on PF, that there aren't more synesthetes lurking about.

Rhody...
 
  • #82


rhody said:
zooby,

If you finish the first half of the book, take a quick peek at my post #34, and feel free to add anything that struck you. I am almost finished with the book, and plan to post the rest of my insights here soon, I will copy the list from post #34 and include the last half in one place for ease of reading. I just looked at Cytowic's personal site and plan to buy, "The Neurological Side of Neuropsychology" next and report back on it. Like I said awhile ago, I think this thread has plenty of life (because of my interest) in it. HeHe. This is a general comment, I can't believe with the fairly large membership on PF, that there aren't more synesthetes lurking about.

Rhody...

I'm thinking there's not a lot to be gained by keeping such careful notes on this particular book. At the time of writing he says ten out of a million people have synesthesia. Of course we all know that's been majorly revised to one in twenty-three people. From the videos you posted we see a large part of the technical data in Shapes is outdated. He's chucked his whole limbic theory as well, which is a main thrust in this book.

The book to take notes on would be his latest, Wednesday is Indigo Blue.

The Man Who Tasted Shapes is still an extremely worthwhile read because of the vivid descriptions you get of the condition from his interviews with the two synesthetes who've accidentally fallen into his lap, and because this book is the story of the revival of interest in the subject, which had been dormant for decades, and more so the story of his giving credibility to the subject. It's really a great introduction to neurology in general for the layman, even better than books by Oliver Sacks.
 
  • #83


hypatia said:
I tend to remember music by smells/scents, but I don't believe I have Synesthesia.

Is there a good definition available? Unlike the word "synaesthesia" describes, lists of synaesthetic experiences include seemingly non-sensory modes, such as learned or cultural concepts such as graphemes and units of time. Along the lines of the quote from Hypatia, metaphores, goose-bump reactions to music, dance etc, are mentioned as related, but I'm not sure how they differ. Eagleman speculates upon further modes of memory, planning, and morality. Emotion appears related. The best definition I've seen is "atypical binding within or between modalities"(Cohen Kadosh). In that case, I wonder about the amount of atypicality.
 
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  • #84


zooby,

I just finished the book, I didn't realize that the Afterword was added in 2002 from pages 231 - 254 and includes some information you may or may not be aware of.
Make sure you have the new book with the afterword, and not an older copy without it. There are a couple of areas in the Afterword I think others will find of interest. When you said in your last post, that since finishing the book, "The Man who Tasted Shapes" he chucked the whole limbic theory, could you elaborate on that. I have to go through the marked pages in the last half of the book and find new observations/facts/tests/testimony that wrap this up. I may read the other book, "Wednesday is Indigo Blue" as well in the future. I will post the remaining summary soon.

Rhody... :cool:
 
  • #85


rhody said:
zooby,

I just finished the book, I didn't realize that the Afterword was added in 2002 from pages 231 - 254 and includes some information you may or may not be aware of.
Make sure you have the new book with the afterword, and not an older copy without it.
Oh! Now you tell me.

Hehe. It's too late. I'm see one of the reasons my copy was probably so cheap is because it's from 1993. Prolly first paperback edition. Doesn't have the update.

There are a couple of areas in the Afterword I think others will find of interest. When you said in your last post, that since finishing the book, "The Man who Tasted Shapes" he chucked the whole limbic theory, could you elaborate on that.
This came out in an offhand remark he made in the long video while he was showing slides of cortical activation of sensory areas. These scans showed that both cortical areas are activated: that of the externally stimulated sense, and that of the concomitant synesthetic sense. In reference to this documentation of cortical activation, he mentioned that formerly he believed that the cortex was inactivated and the limbic system hyperactivated. He says, with a touch of embarrassment it seemed, something to the effect "We've had to put all that thinking behind us now." (I haven't rechecked the video, so that's an anecdotal recollection.)

I didn't construe that to mean he doesn't think the limbic system participates, (it has to be adding the strong emotional associations, at least, and also performing the memory formulation that is so strong in synesthetes), but it would mean he no longer believes the limbic system participates in the manner he used to suspect. In a separate paper I found, about five years back, he said that he suspected the mixing was specifically taking place in the hippocampus. That makes a certain amount of sense if you believe the cortex is silent. This newer evidence of cortical activation ought to shift the salient limbic involvement to the thalamus. The thalamus is the "conductor" of the cortical "members of the orchestra". Synesthesia would result if the thalamus misdirected both the violins and the brass to play the violin part, metaphorically speaking.

I have to go through the marked pages in the last half of the book and find new observations/facts/tests/testimony that wrap this up. I may read the other book, "Wednesday is Indigo Blue" as well in the future. I will post the remaining summary soon.
I still have a hundred or so pages to go. I'll wait to see if I feel like jumping right to "Indigo Blue". I also ordered "Synesthesia: a Union of the Senses" because I found a dirt cheap copy on ebay. In most places it's on the expensive side. I bid on, and won, a copy for $5.00. (It says it's a "signed" copy. I don't know if that's supposed to mean autographed by Cytowic or that it's defaced by the signature of some former owner.)
 
  • #86


zoobyshoe said:
Oh! Now you tell me.

Hehe. It's too late. I'm see one of the reasons my copy was probably so cheap is because it's from 1993. Prolly first paperback edition. Doesn't have the update.


This came out in an offhand remark he made in the long video while he was showing slides of cortical activation of sensory areas. These scans showed that both cortical areas are activated: that of the externally stimulated sense, and that of the concomitant synesthetic sense. In reference to this documentation of cortical activation, he mentioned that formerly he believed that the cortex was inactivated and the limbic system hyperactivated. He says, with a touch of embarrassment it seemed, something to the effect "We've had to put all that thinking behind us now." (I haven't rechecked the video, so that's an anecdotal recollection.)

I didn't construe that to mean he doesn't think the limbic system participates, (it has to be adding the strong emotional associations, at least, and also performing the memory formulation that is so strong in synesthetes), but it would mean he no longer believes the limbic system participates in the manner he used to suspect. In a separate paper I found, about five years back, he said that he suspected the mixing was specifically taking place in the hippocampus. That makes a certain amount of sense if you believe the cortex is silent. This newer evidence of cortical activation ought to shift the salient limbic involvement to the thalamus. The thalamus is the "conductor" of the cortical "members of the orchestra". Synesthesia would result if the thalamus misdirected both the violins and the brass to play the violin part, metaphorically speaking.


I still have a hundred or so pages to go. I'll wait to see if I feel like jumping right to "Indigo Blue". I also ordered "Synesthesia: a Union of the Senses" because I found a dirt cheap copy on ebay. In most places it's on the expensive side. I bid on, and won, a copy for $5.00. (It says it's a "signed" copy. I don't know if that's supposed to mean autographed by Cytowic or that it's defaced by the signature of some former owner.)

zooby,

I am not worried, I know I am in good company here, we will get it right and sorted out, after all, that's what doing research is all about. Hey, I didn't know I could be a poet too. hehe

Rhody...:biggrin:
 
  • #87


Particularly regarding grapheme-colour synaesthesia, and looking at VBM, MEG, fMRI and EEG data, a lot of interest lies in the fusiform gyrus amongst other areas, for example-

V4/V8 is mentioned by Nunn et al., 2002
http://www.psych.ndsu.nodak.edu/mcco...nesthesia).pdf

Weiss and Fink, 2008 mention the fusiform gyrus and parietal cortex.
http://brain.oxfordjournals.org/cgi/.../full/awn304v3


In Hubbard, Arman, Ramachandran & Boynton, 2005 "Neurocognitive Mechanisms of Synesthesia" there is also the prediction that-

In lower synesthetes, we suggest that crossactivation may occur between adjacent regions of the fusiform gyrus involved in letter recognition and color processing, whereas higher synesthesia may arise from crossactivation in the parietal cortex, particularly in the region of the angular gyrus, the ventral intraparietal area, and the lateral intraparietal area (Hubbard et al., 2005b).
http://www.unicog.org/publications/H...onReview05.pdf
 
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  • #88


http://docs.google.com/viewer?a=v&q...3zDVFw&sig=AHIEtbTtrwzDwuLK0KL0kOWOLwD_wnlplw


This is a bit old, 2006, but I think it answers my question to a large extent, in that it may be impossible to have a good definition yet. Amongst other possibilities, it is possible that everyone is born with this and that state changes, or it is possible, more broadly, that it is something that everyone has and it remains with them, to some degree. Such possibilities are evidenced in acquired synaesthesia, like in those who have lost or impaired modes, and in induced synaesthesia, for example, hypnotism amongst other research-

Linking is not working, but the paper is called "Induced Cross-Modal Synaesthetic Experience Without Abnormal Neuronal Connections", Cohen Kadosh et al.

As well, the paper discusses prevalence of cross-modality, as well as possible underlying universals and possible mechanisms common to synaesthetes and non-synaesthetes alike.
 
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  • #89


rhody said:
I am not worried, I know I am in good company here, we will get it right and sorted out, after all, that's what doing research is all about. Hey, I didn't know I could be a poet too. hehe
All neurolgists are natural poets, a fact I invented just now.

Rhody, I am afraid I have just discovered the book ends on page 152, the end of the chapter about the xenon gas test. After that Cytowic goes off into off-topic rants about attitudes that bother him. Way too much opinion, not enough synesthesia.

I discovered the San Diego Public Library system has 4 (FOUR) copies of Wednesday Is Indigo Blue, but they are all checked out! This seemingly obscure subject is certainly becoming pretty popular.
 
  • #90


I hesitate to mention this, that being said, I wanted to relate a brief experience I had yesterday, late in the day while reading a boring article on a PC. The background was off white with uniform back lettering in my field of view, no graphics, color, different fonts, etc..

I was forcing myself to read it, after awhile my head dipped a bit and I nodded off for a bit and when my autonomic reflex action took over my head snapped up, and the display changed, but only for a second when I opened my eyes, before and after each word in the normal whitespace areas were small half moon semi-circles that were a blood red color.

I was still pretty tired and this did not register, and I nodded off a second time, this time my field of view was lower on the screen and horizonally across a single line two words appeared to be highlighted in light green, while one was what I would call a burnt orange. After the second rebound, I woke up fully and the recognition of what I just had experienced sank in. If it were not for studying synesthesia I doubt I would have paid attention, or noticed the extra background color, so to speak.

I will only believe it is not part of an active imagination when it happens again. If I have a nodding off experience and see similar colors with the same stimuli will I think that I had a glimpse into what some experience daily. It was not unpleasant or distracting at all, just added input that I was easily able to deal with.

Rhody...
 
  • #91


rhody said:
If I have a nodding off experience and see similar colors with the same stimuli will I think that I had a glimpse into what some experience daily.

This experience suggests the mechanism might be discovered in the information we have about how brain functions change between wakefulness and sleep.
 
  • #92


zoobyshoe said:
This experience suggests the mechanism might be discovered in the information we have about how brain functions change between wakefulness and sleep.

I've seen a couple of references to research or to a paper relating this with cross-modality, possibly authored by Sagiv again, but haven't actually seen any work.
 
  • #93


This is a continuation of post #34, the first half of the book, numbers 16 and greater are the last part. I wanted to keep it all together and to remind myself as I complete my short (but detailed when needed) summary.

1. Mingling of two or more of the sensations (sight, sound, touch, taste, smell) in a cross modal fashion. Most commonly reported is color and hearing.

2. Synesthetic experience is constant and stable (same stimulus results in same response) for the most part. There is no known abnormal pathology known to it.

3. More women than men have it, or at least are reported to admit having it.

4. Seven of the forty two individuals studied by Cytowic had immediate relatives who had it, suggesting there is a genetic component to it.

5. There is no known agreement when those with mixed sensations of say color hearing when two individuals with that trait were compared, their experiences and descriptions were completely unique to the individual describing them.

6. Cytowic was impressed at how highly individualized the triggering stimuli usually are, explaining why the expression of synesthesia vary from person to person. It is an all or nothing trait, and some people seem to have it more than others.

7. Human imagination fill the gaps of those (without it) in trying to understand it. Those who experience it daily have trouble describing the "ineffable quality" of it, leading to bewilderment and confusion of those trying to grasp it. It must be experienced, and cannot be imparted or transferred to others.

6. Failure of tests for items 5 thru 7 above lead Cytowic to a more qualitative investigation of the triune brain, from the bottom up, from the primitive brain (brain stem structures), to the limbic system, and finally to the cortex to determine the origins) of the mixed sensations that those with syesthesia experience. Were one or more of these structures responsible, and if so which and why.

7. Cytowic designed and administered a series of tests designed to qualify what those people experiencing synesthesia were sensing, this result being what is known as "Form Constants", now believed to be a limited number of perceptual frameworks, that appear to be built into the nervous system and are probably part of our genetic heritage.

8. Synesthesia can be induced temporarily by those who use LSD. LSD exerts three physiological actions, two of which oppose one another. It enhances low-level synapses coming from the brainstem relay, the hypothalmus, and at the same time suppressing the synaptic connections between the hypothalmus and high brain areas. Third, LSD causes an overall alertness and enhancement of synaptic pathways to the limbic system, the part of the brain that gives meaning to events and is concerned with emotion and memory. This part is key, "by blocking the normal flow at a point before a unified experience is created, LSD makes it 'stick" at a detail of the perception, like when a phonograph needle skips and plays the same part of a record over and over.

9. Those with synesthasia have great memory for detail, and an indelible recollection of the synesthetic event itself.

10. Temporal Lobe Epilepsy (TLE) can result in the joining of the elements of smell, taste, vision, touch and hearing, memory and emotion and epileptic synesthesia occurs in four percent of TLE events. A personal observation here, compared to people with lifelong synesthesia I can imagine it must be very frightening to suddenly be barraged with a 'mingling of the senses", whereas people who have synesthesia are used to its stimuli and effects.

11. Cytowic and Dr David Stump, an expert in measuring brain metabolism, used a cerebral blood flow (CBF) technique in which a radioactive isotope of xeon (harmless inert gas) is used to identify what areas of the brain are processing, given the blood and glucose is being delivered and consumed, with a helmet device fitted with radiation detectors (16) measuring 16 different brain regions while the subject engages in a task, in this case one that induces a synesthesia response.

12. A baseline state was taken, then two tests were conducted, one to simply stimulate the patient with a stimuli that resulted in a synesthesia response, and the second test, this time adding amyl nitrate (to boost the synesthesia response).
All three tests, baseline, normal stimuli, and normal stimuli with amyl nitrate went smoothly each lasting about eight minutes.

13. Review of the data yielded the following: baseline, low flow for someone the patients age, normal stimuli resulted in the blood flow to the left hemisphere of the patients brain at 18% less than in the baseline, that's right, than in the baseline, Holy crap ! The amount of flow is three times below the accepted flow of a normal person's. This was the first time Dr Stump (who was stumped, pun intended) had ever seen a reduced flow during the activation task (in this case a stimuli that brings on the sensation of synesthesia). The same effect was observed when amyl nitrate was administered. Synesthesia does not occur in the cortex, basically it shuts down when it occurs. The energy is being stimulated in the limbic brain, in the area where zoobyshoe describes as the hippocampus, which up to now I was under the assumption has to do with the storing of new memories, which makes sense in that people with this trait are able to retrieve them in great detail. I just didn't realize that it may be an area where a mingling of the senses occur. One point to note, the limbic system is deep enough that its metabolic activity is beyond the range of the CBF test to detect it.

14. Drugs can either stimulate or block the effects of synesthetes as follows:
The human cortex as we will see later plays an important part in either enhancing or dulling the effect of synesthasia.

15. As a rule when the cortex is depressed (reduced blood flow results in enhanced synesthesia effects) and when stimulated (increased blood flow results in a dulling or blocking effect of the sensation), Amphetimines block or dull the effects of synesthesia, while alcohol and amyl nitrate enhance it.

16. In 1922 Max Planck's principle dictates that of all possible paths, the one selected is the one that uses the least possible energy.

17. The limbic system processes input quickly, enhances cortical processes, and by extensive reasoning, reduces entropy, acts on incomplete information, creates order from continuous and incoherent of sensations, this gives humans their esthetic capacity. This capacity to determine relevance is what makes us unpredictable and creative.

18. The brain stem and cerebellum provide an action component for motor output, the model of the world is contained in the cerebral cortex, while the critic lives in the limbic system.

I think I understand (basically two main concepts) so far, areas of the brain operate at different frequencies and when triggered by a visual, sound, smell, taste, or touch stimulus can cause other areas in the brain, (normally suppressed to everything but that stimulus) to create a near simultaneous activation in the brain which for most of us is silent because the adjacent processing area in the brain does not respond.

19. Cytowic in his afterward (page 243) published in 2003 puts the elaborate and at time simplified explanation to rest, in 2002, a functional MRI study by Julia Nunn confirmed what was long expected: V4 activation (without V1 or V2 activity(early visual areas)) in synesthetes who see color in response to spoken words. Whereas both synesthetes and controls activated auditory and language areas as expected, the synesthetes also activated the color area (V4), but only on the left--in agreement with earlier results. Such lateralization is tantalizing, given their color experiences were not confined to the right visual field. The fMRI technique, which is the most refined one we have to date, also disclosed activation in transmodal areas concerned with memory and affect, consistent with both the subjective statements and clinical observations of synesthetes.

An unexpected result of this study was when actually viewing colored surfaces, synesthetes don not activate their left V4, the area for color. Right V4 did function for both synesthetes and controls. Ordinarily viewing colors activates both right and left V4, as well as ealry visual areas V1 and V2. The implication therefore, is that participation of left V4 in synesthetic color experience renders it unavailable for color perception--in other words, synesthesia appears to have hijacked an existing brain function. This surprise is consistent with the observation that nonsynesthetes merely imagining colors (compared to performing a visual control task not involving color) do not activate V4, Thus the brain basis of synesthetic color experience is consistent with real color perception rather than color imagery. This refutes earlier criticisms that synesthetes are just "making it up" or have "overactive imaginations."

20. Most who study synesthesia now believe that inheriting an X-linked dominant genertic mutation results in failure in synesthetes' brains to prune juvenile projections between brain structures that normally exist temporariliy during the development of all brains. Everyone is born synesthetic, only to lose the capacity as the brain matures.

21. An exception to the people who have not had their brain structures pruned is when we are able to quiet the chatter of our cognitive mind. Roger Walsh of the University of California (2002) has evidence to support it. He says synesthasia is one hundred times more common in meditative states compared to baseline prevalence. With increasing levels of experience, the numbers who experience synesthesia increases (35% vs 63%). Even within the most inexperienced beginners groups those experiencing synesthesia had twice as much average practice time (17 years) than those who did not experience synesthesia (8 years). Among a third group who had between 24 to 31 years of practice, over half had polymodal experiences and also perceived categories synesthetically--thoughts, emtions, and images felt as a sensation. For all three groups, synesthesia was most apparent during meditation.

I will add the remaining information on the binding problem and the linking to metaphor and language tomorrow evening before the thread is no longer editable.

I hope you all have enjoyed this wild ride. I know I have.

P.S.

Here is some background info I was looking at while researching this post:

Here are a couple of useful videos for context: http://www.youtube.com/watch?v=g6KpIrKCDwg"

I found this paper: http://www.google.com/#hl=en&q=alph...&oq=alpha+frequ&gs_rfai=&fp=84c7fb41710deb10"

Rhody... :biggrin:

Zooby: Fixed #1, sorry I missed it. More this evening...
 
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  • #94


rhody said:
zooby,

I think this thread has plenty of life...

Rhody...

You're welcome
 
  • #95


Rhody, # 1 needs to be fixed. The most common, as reported by Cytowic at that time, was Colored Hearing.

See page 51:

"I had soon found many cases of synesthesia recorded in both the scientific and general literature, as well as two books devoted to it. Colored Hearing was published in French in 1890, while a German text appeared in 1927 called Colored Hearing and the Synesthetic Factor of Experience. Most accounts emphasized colored hearing, which I discovered was the most common form of synesthesia."

Since this book was published we know he's declared that Grapheme -> Color syesthesia is the most common.

The kind experienced by the title 'character,' taste -> touch is, incidentally, an exceptionally rare form. Cytowic's life's work was sparked by his accidental encounter with an extremely unusual case.
 
  • #96


flatmaster said:
You're welcome

Flatmaster,

No disrespect intended to you the OP, thank you for starting this thread...

Just curious, did you have a chance to look at this thread, started back in March, https://www.physicsforums.com/showthread.php?t=374522" Post #7, that's where this whole little adventure into synesthesia started, with zoobyshoe mentioning Cytowic's book ? I took the bait, bought it, read it, and the rest they say is history.

Rhody...
 
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  • #97


So, Rhody, the question is, having finished the book, what did you find salient? What stands out in your mind? How did it alter your conception of things?
 
  • #98


zoobyshoe said:
So, Rhody, the question is, having finished the book, what did you find salient? What stands out in your mind? How did it alter your conception of things?

zooby,

I was in the process of updating my post last night with the summary and it timed out so I lost everything I was typing, not cool. I will add a summary on the binding problem in a bit, I just don't feel like trying to recreate it all from scratch right now.

I enjoyed the book, and like any investigator I have more questions (focused this time with a bit of background to guide me). I want to know the area name or names associated with all five senses, the book focused on the sight color areas extensively, most likely because there were few subjects to test with the rarer forms of synesthesia, for instance smell -> sound 0.3%, touch -> smell 0.3%, taste -> hearing 0.3% (from 365 cases compiled by Sean Day Ph,D. moderator of the synesthesia list) as well as combined rare sense ones.

I want to find a case whether person has bi-directional synesthesia and how it debilitates them, keeping them out of society because of the confusion caused by the reverberating sensations, that must be an awful way to live.

A personal observation, if the day comes that a very well produced documentary appears on Frontline, 60 Minutes, or 48 Hours, and all the media attention that goes with it awakens the world to synesthesia, that someday in the not too distant future Dr Cytowic and Dr Eagleman may wake up to find shiny little gold Nobel medallion(s) around their necks. That is my humble and biased opinion.

Rhody...
 
  • #99


If you're in the mood to ponder debilitating things, take a break from synesthesia and get a quick and tragic tour of what the hippocampus is all about:

Clive Wearing - the man with no memory
https://www.physicsforums.com/showthread.php?t=315603

This will show you, among other things, why Cytowic's early theory of the hippocampus as the "location" of synesthesia didn't really make much sense. The hippocampus is about memory. Everything's connected to the hippocampus because every experience is always being compared to memory.

Watch the videos when you have time but also be sure to read the excellent article by Sacks:
OliverSacks said:
Episodic or explicit memory, we know, develops relatively late in childhood and is dependent on a complex brain system involving the hippocampi and medial temporal-lobe structures, the system that is compromised in severe amnesiacs and all but obliterated in Clive.
http://www.newyorker.com/reporting/2007/09/24/070924fa_fact_sacks?currentPage=all
 
  • #100


rhody said:
A personal observation, if the day comes that a very well produced documentary appears on Frontline, 60 Minutes, or 48 Hours, and all the media attention that goes with it awakens the world to synesthesia, that someday in the not too distant future Dr Cytowic and Dr Eagleman may wake up to find shiny little gold Nobel medallion(s) around their necks. That is my humble and biased opinion.

Rhody...

Going back further, I think it is interesting that Francis Galton, who first described this sort of thing, and who wrote that the “tendency is very hereditary” (Sir Francis Galton, 1883, "Inquiries into Human Faculty") was Charles Darwin’s relative. They were half-cousins, who shared a Grand-Father in Erasmus Darwin, who wrote a treatise on “generation”, which was influenced by associationism, and which anticipated Lamarckism. Galton and Charles Darwin were also generally friends who visited, and corresponded with, each other.
 
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  • #101


fuzzyfelt said:
Going back further, I think it is interesting that Francis Galton, who first described this sort of thing, and who wrote that the “tendency is very hereditary” (Sir Francis Galton, 1883, "Inquiries into Human Faculty") was Charles Darwin’s relative. They were half-cousins, who shared a Grand-Father in Erasmus Darwin, who wrote a treatise on “generation”, which was influenced by associationism, and which anticipated Lamarckism. Galton and Charles Darwin were also generally friends who visited, and corresponded with, each other.

Yes indeed, I found about this yesterday. Francis Galton was quite a scientist, and he made many contributions in various fields

http://en.wikipedia.org/wiki/Francis_Galton
 
  • #102


This is a continuation of post #93. Making additions to #1 with rarer types of synesthesia, all other stuff is new starting with #22.

1. Mingling of two or more of the sensations (sight, sound, touch, taste, smell) in a cross modal fashion. Most commonly reported is color and hearing. Rarer types: page 232 from Dr Sean Day's study of 365 cases, all in percentages:

Note: The first group are grapheme associations, the rest, rarer still are mingled sense sensations:

colored time units: 19.2
colored musical sounds 14.5
colored general sounds 12.1
colored phonemes 9.6
colored musical notes 10.4
colored tastes 6.3
colored personalities 4.4
colored pain 4.4 (woah, I would like to hear from someone with this trait)
colored odors 5.8
colored temperature 2.2
colored touch 1.9

and

sound -> touch 2.7
sound -> taste 2.7
sound -> smell 1.1
sound -> temperature 0.5
taste -> touch 1.1
taste -> hearing 0.3
touch -> taste 0.5
touch -> hearing 0.5
touch -> smell 0.3
vision -> taste 1.9
vision -> hearing 1.1
vision -> smell 1.1
vision -> touch 0.8
smell -> touch 1.1
smell -> sound 0.3

22. 1923 Max Planc defined a principle that says, among all possible paths, the one taken is always the one that uses the least energy. The principle finds itself exquisitely expressed in the efficiency of the human brain.

23. It is worth noting the rates at which parts of the brain are believed to process information (internally) and accept input from and provide input to:
a. Limbic system (400 hz internal clock), inputs to/outputs from 5 hz, 80/1 ratio
b. Cortex (high speed internal clock, rate not provided) , inputs to/outputs from 10 hz
c. Communication between limbic system and cortex: 2:1 ratio

The rest of the summary is from the Afterword published in 2003.

24. Cytowic's definition of the characteristics required for synesthesia:
1. Involuntary and automatic
2. Spatially extended
3. Consistent and generic
4. Memorable
5. Affect laden (carrying a sense of certitude, trivial tasks are filled with "emotional effect", mostly pleasurable, except in rare cases: vile tasting words, or nausea hearing a voice or musical instrument.

I originally said I was going to report on The Binding Problem, and Metaphor and Language. It turns out that only the Binding Problem presents new information (to me anyway).

25. Binding problem summary: diverse attributes are processed in different areas and at different times in the brain. Consider the perception of: color, orientation and motion, according to Cytowic they are processed in this order but with a delay of 30 ms between color and orientation, and a 40 ms delay between orientation and motion. How does the brain process this and make it seamless ?

26. Cytowic suggests the brain searches for "constancy" by assigning essential features to a category. The mystery is how the brain perceives and processes constantly changing input, assigning objects their constant features.

27. Cytowic suggests a new model for processing within the brain, taken from chapter 6: Synesthesia: A Union of the Senses, summarized by:
1. Distribution of function across structures.
2. Simultaneity of activity on several levels
3. Use transmodal (not pertaining to anyone sense) models (V4: color, V5: motion and direction) that do three things:
a. Construct multi-sensory representations of the world
b. Lend memory and affect to experience
c. Participate in establishing categories via groups of coarsely tuned neurons.

28. The model organizes brain tissue into five major networks (one per sense), and many lesser distributed systems, a critical idea here is one of multiple synaptic levels being active simultaneously, with each node capable of influencing the state of adjacent levels (resulting in a synesthetic experience).

And that, my friends is a brief summary of the book...

Rhody...
 
  • #103


Here is an example of what a long term of what someone who has meditated for over 20 years can achieve, http://www.youtube.com/watch?v=LFFMtq5g8N4&feature=fvw" he shows how he can quiet all areas in his brain and describes the frequency ranges, and shows proof on a portable EEG machine, bringing to a halt all measured frequencies on the EEG during meditation.

Here is his http://www.kenwilber.com/blog/list/1" if you play his second video, "The Sky Turns into a Bog Blue Pancake", fast forward to 4:20 where he says, "you can actually taste the sky in that sense", definitely a synesthetic connection, he goes on to say how viewing a mountain, he can actually touch it. It seems Ken has multi-sensory synesthesia (taste, touch), as a direct result of decades of meditation.

So we have concrete proof and testimony from someone who has meditated for over two decades and what he has been able to achieve, here is his http://en.wikipedia.org/wiki/Ken_Wilber" .

Here is an older (2002) testimony of http://serendip.brynmawr.edu/bb/neuro/neuro01/web1/White.html" , who describes a synesthetic experience, but only while dreaming. See her description below.
When I was very young, I experienced a recurring dream that I was staring, entranced, at a delicate white flower. It was like nothing I had seen or experienced in my waking life, because the pristine, thinly-veined petals were such an exquisite color that it manifested itself upon my dreaming brain as a color and a sound. The white song was a single note - like a distant choir lifting its voice in concerted wonder. I would wake from the dreams bewildered at the ease with which my brain, when asleep, could produce in me a tangle of sensations I could never enjoy while conscious.

Rhody...
 
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  • #104


I call hogwash. The only way an EEG can show no brain activity is if you're brain dead, you don't have the EEG hooked up correctly, you're faking the EEG reading, or you're only showing part of the EEG.

And of course, the wikipedia article says:
Wilber describes the current state of the "hard" sciences as limited to "narrow science", which only allows evidence from the lowest realm of consciousness, the sensorimotor (the five senses and their extensions). What he calls "broad science" would include evidence from logic, mathematics, and from the symbolic, hermeneutical, and other realms of consciousness.
If that's true he really has no idea what science is. Science is "narrow" because it only deals with what can be repeatedly observed and proven? What a moron.
 
  • #105


Zooby,

Have you ever heard of someone having a synesthestic experience only while dreaming and not awake as in the case of Sadie White listed above ? That was a first for me, which is the reason that I mentioned it.

Rhody...
 

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