The Quantum Pontiff

A very cool discovery out of Caltech: auditory synesthesia. Synesthesia, you probably know, is an effect wherein the stimulation of one sense causes automatic sensations in another sense. For example, grapheme-color synesthesia is where numbers or letters appear to those observing to be shaded or tinged with different colors. Now two researchers at Caltech, Melissa Saenz (Who I know! I know someone who discovered something really cool!) and Christof Koch, have identified a new form of synesthesia, auditory synesthesia. To describe it, it’s funner to read what Dr. Saenz has to say about how it was discovered.

“While I was running an experiment at the Caltech Brain Imaging Center, a group of students happened to pass by on a tour, and I volunteered to explain what I was doing,” explains Saenz, who, along with Christof Koch, the Lois and Victor Troendle Professor of Cognitive and Behavioral Biology at Caltech and professor of computation and neural systems, reports the finding in the August 5 issue of the journal Current Biology.

“As part of the experiment, a moving display was running on my computer screen with dots rapidly expanding out, somewhat like the opening scene of Star Wars. Out of the blue, one of the students asked, “Does anyone else hear something when you look at that?” After talking to him further, I realized that his experience had all the characteristics of a synesthesia: an automatic sensory cross-activation that he had experienced all of his life,” says Saenz.

A search of the synesthesia literature revealed that auditory synesthesia–of any kind–had never been reported. Intrigued, Saenz began to look for other individuals with the same ability, using the original movie seen by the student as a test. “I queried a few hundred people and three more individuals turned up,” she says. Having that specific example made it easy to find more people. That movie just happens to be quite “noisy” to the synesthetes and was a great screening tool. When asked if it made a sound, one of the individuals responded, “how could it not?” I would have been less successful had I just generally asked, “Do you hear sounds when you see things move or flash?” because in the real environment, things that move often really do make a sound,” for example, a buzzing bee.

This may be why auditory synesthesia hadn’t been detected by neurobiologists. “People with auditory synesthesia may be even less likely than people with other synesthetic associations to fully realize that their experience is unusual. These individuals have an enhanced soundtrack in life, rather than a dramatically different experience, compared to others,” says Saenz. However, when asked, all of the synesthetes could name examples of daily visual events that caused sounds that they logically knew to be only in their minds, such as seeing a fluttering butterfly or watching television with the sound turned off.

Very cool stuff, I must say, and the way it was discovered is just, well its just cool, I must say. Even better, the researchers believe that the effect may be very common. Which is great because if you go this demo page you can watch a video which tests whether you have got da auditory synesthesia. I’m hoping that beyond my mom and my wife and my dog who read this blog, maybe there are enough people out there to actually find one who tests positive in this test. If you do, please comment! It would be great to hear from someone for which this isn’t just a press release.

For those interested, the paper describing this research is here and a Nature News article here.


  1. #1 Markk
    August 6, 2008

    Rats, One negative anyway. Although it was funny that I could perceive “myself” trying to convince “myself” to hear a whooshing noise.

  2. #2 Jan
    August 6, 2008

    I heard something. A… faint buzzing/whirring/whooshing sound that changed along with the image. It sounded vaguely electronic in origin and was subtle enough – or else I’m so used to this phenomenon – that at first I thought it was just part of the background noise of the office. Then I realized it was changing in time with the video. And it seemed to come from my ears, rather than being something I was imagining.


  3. #3 Dave Bacon
    August 6, 2008

    Wow, interesting Jan. Have you ever noticed anything similar before?

    I’m especially intrigued by the fact that this could have gone undiscovered in such a large portion of the population…but I can totally buy why this might occur (that’s non-scientific Dave talking 🙂 )

    I actually spent a long period of time in high school trying to figure out if I could train myself to actually hear music without there being music. I could never convince myself that I’d succeeded. A large chunk of my brain is tied up in music, I think, because I constantly sing songs and hum and whistle…when I’m not listening to music while working. I’d love to spend time thinking about cross sensory research 🙂

  4. #4 JohnQPublic
    August 6, 2008

    Does that explain the smell when reading string theory?

  5. #5 CRM-114
    August 6, 2008

    Negative. Rats. Normality ain’t all it’s cracked up to be.

  6. #6 Daniel D. Brown
    August 6, 2008

    Definitely some cool research. It serves as an excellent reminder of how far we really are from understanding the (seemingly) less complex wiring and function of sensory perception. I’m ready to to know how more complex things like consciousness emerge from these pathways NOW dammit 🙂

    Ah well, perhaps in our lifetimes…

    Excellent blog by the way.

  7. #7 Becca
    August 6, 2008

    I heard a sound… and then looked up and realized it was from my lab. DARN!

  8. #8 speedwell
    August 6, 2008

    I’m not sure this counts. I had to loop the video to get any effect. The dots, when moving, did not make a sound, but at each point where expansion stopped and turned into a contraction and vice versa, I heard a very distinct “whump” sort of noise, midway between how your heartbeat sounds to you when you concentrate on it, and a very soft playback of a recording of an entire orchestra playing a single chord at precisely the same time, very emphatically. The same “noise” sometimes wakes me up when I’m about to doze off in a long, boring meeting or when I’m sitting up too late.

  9. #9 Cherish
    August 6, 2008

    The only thing I heard was the wormhole theme from Stargate.


    It was silent in this brain.

    Could this perhaps have some relation to the way people think or learn?

  10. #10 Jel
    August 6, 2008

    nothin, except I imagined I heard pebbles scraping together softly as dots went into middle. I reckon that was just imagination – finding what you’re looking for. I mean we all hoped we were that little special didn’t we? What if you’d told us that hearing a noise meant we were probably also slightly less intelligent than average?

    Jan’s response sounds a bit contrived to me – a bit like my experience. I reckon you’d have to hear the sound quite clearly.

    Test would be more valid if we watched it and were simply asked what did we notice? followed by ‘ok and was there a sound’?

  11. #11 Page
    August 7, 2008

    I wonder if they had any problems distinguishing between people with tinnitus and those with auditory synesthesia? I also wonder if people with tinnitus experience variation in their inner tone when they are using other sensory modalities?

  12. #12 Anandi
    August 7, 2008

    Hey! I know Dr. Saenz/Melissa too! How cool. I’m the person who associates letters and numbers with colors, though I don’t actually physically see them that way. It’s just that sometimes I think certain colors/words should *be* a specific color, or that the color someone chose is just not right for those words/letters/numbers.

    I can’t get the movie to work. But I’ve never noticed hearing things when they weren’t there.

  13. #13 Matthias
    August 10, 2008

    Nope, no reaction on the video.

    What I did notice when I was a child (maybe around 10ish) was that I could “hear” CRT televisions in a constant high pitch beep. I *think* this one’s for real when they are actually running, but I could hear it even when they were completely off – sometimes even out of sight. It was enough for me to know that there was a telly there, and i could hear it.

    The effect’s not so strong nowadays, although I do still hear that sound occasionally, mostly just out of the blue (might as well just be a mild Tinnitus). I also have the feeling as if it was there all the time, and i was just so used to it I would only notice it when it increases (or does noticing it increase it?).

    It also came back almost instantaneously as I thought about it and looked at the telly in my room

  14. #14 Bradford Holcombe
    August 20, 2008

    Absolutely! Two distinct tones for each direction. Sounds sorta like the noise of a TV turned on, with the sound turned off; a very high-pitched whine. I have heard this effect for years. I always thought that something in display cards made noises when drawing such things. I thought I had really good hearing. Turns out, it is all in my head!

  15. #15 David
    August 22, 2008

    Now I can’t trust my senses. As soon as the video started, my mouth started watering. Oy.

  16. #16 Leslie
    August 26, 2008

    Looks like you have a 0.5 negative. Not quite sure if i actually heard something, or that my ears are super sensitive .. so that i can basically hear anything. Though i thought the sound frequency of my environment changed when i looked at the moving image. But i didn’t quite hear a loud buzzing sound. Hopefully i can find out more about this synesthesia, i think i have a different type of it.

  17. #17 kate
    November 20, 2008

    Hey I see colors for numbers and letters too!!!!!!! I also see colors for sound!!!!!!!! I didn’t know what synesthesia was untill a month ago when i read a book!!!!

  18. #18 stephen
    February 28, 2009

    There is a pitch change from AAAAA to OOOOOO i also see music.

  19. #19 Claudia
    July 5, 2009

    I’ve seen the display before; it’s on YouTube now. I have a few types of synesthesia, and the image makes this bizarre sound like someone breathing in your ear.

  20. #20 GameGuru
    July 14, 2009

    Do you know the spongebob theme song? In a quiet, quiet place where there is NO sound, perhaps before going to sleep, you can repeatedly think about it. If you think/play the spongebob theme song in your head long enough, you will think you can hear it. No kidding, you will think you can HEAR it. You will pull out a microphone, set it on record, and place it next to your ear!

  21. #21 Dy-Anne
    August 2, 2009

    i did not hear anything.

    though i think i have something similar but i have not been able to find anything on it — insteado f hearing a noise with a sight i get visual disturbances for sudden noises. like when my husbands coughs – i will see a wave – like a heat wave in the lower part of the vision of my left eye. it happens everytime. its really annoying. (esp since he is a smoke and coughs all the time)

  22. #22 Nathan
    August 5, 2009

    I heard some sounds. It was higher pitched as the dots came nearer, and it lowered when they receded. I think that I may have a form of synesthesia, because I see colors with different musical instruments. The brightness of the color is associated with the horn. Percussion are very bright, ex. snare and keyboard, low percussion are very dark. Trumpets-yellow, F horn-cloudy magenta, trombone-cloudy blue, euphonium, basoon- dark pink, tuba-navy blue, clarinet-brown, flute-light blue, saxophone, guitar-orange. And other various ones. It’s harder to distinguish the colors when the full orchestra is playing, but become clearer if there is a soli. The colors also move if the tempo or phrasing changes.

  23. #23 Larissa
    August 26, 2009

    I agree in general with Dy-anne and nathan- i always see colors and moving shapes when I hear sounds like music. – I have an interesting music taste, I love techo because all the colors and shapes pop out better then more blended music. If I turn up the music really loud at night with some songs it’s like I can reach out and touch them. of course I also have the grapheme color synesthesia too. -keep up the research i guess thanx 4 the post

  24. #24 Chloe
    August 27, 2009

    I had no idea that this was synesthesia! I hear a high pitched ring almost every time something moves in such a way. or if it’s flashing. This has always always happened to me.

  25. #25 nathan buchanan
    September 5, 2009

    lol i was watching this on youtube and didn’t know what it was. the sound of a distorted siren was driving me crazy as i was watching it though. a very loud, red, distorded siren sound. now i know. . .

    that’s so crazy lol

  26. #26 Jim Dodds
    September 14, 2009

    Yikes! I had the insight Saturday that tinnitis is actually synesthesia, when some headlights crossed my path and my ear noise flared up. Now this! Whoa!

  27. #27 Teresa Downwright
    September 19, 2009

    No, I didn’t hear anything when I watched this video, except that I smelled hot ash. Maybe I have a different kind? One that associates sight with smell?

  28. #28 lianna
    September 21, 2009

    I hear the sound of a squeaky floorboard when its stepped on. Wow this is really weird, other people see or smell different things.

  29. #29 manda
    September 26, 2009

    I heard a whoosing sound; I have graphmere color synesthesia, OLP synesthesia, and some other synesthesia experiences…I’ve never heard of this one before. I’d love to find out more; One of the things my synesthesia does is that music has shapes and colors for me. Could that possibly have something to do with this?

  30. #30 Kai
    October 5, 2009

    When I watch it, I “hear” an in and out whooshing sound, but it’s not as obvious as an external noise. It’s easily crowded out if other noises are happening around me.

  31. #31 Sandra
    October 10, 2009

    I didn’t hear anything. I have the opposite kind of synesthesia. I see and feel sounds. It’s usually pretty cool but kind of annoying when I’m in a quiet room and then one person is talking really loudly.

  32. #32 acı cehre
    October 10, 2009

    I have the opposite kind of synesthesia. I see and feel sounds. It’s usually pretty cool but kind of annoying when I’m in a quiet room and then one person is talking really loudly.

  33. #33 Cherie
    October 29, 2009

    That was way cooool!!! A whooshing, deep hum that increased in intensity then reversed itself… tasted sour increasingly and decreasingly too.

  34. #34 Nonny Kor
    November 2, 2009

    i watched with one eye only, and switched… then when i watched with both together, the dots got bigger and ran sideways… and hypnoticallly… i’m really kinda deaf, so would have loved to have heard ANYthing! bummer……. loved the comment above about tinnitus… if i didnt hear that, i wouldnt hear anything… (deaf joke, sorry)…… thanx for posting this… interesting.

  35. #35 Annette
    December 1, 2009

    I heard it. I have a lot of different synesthesia types, but I didn’t know that this was another one. Really very cool. I have a buddy who can look at stuff like this and taste it. Often, if you have one form, you have many others. It’s quite a gift and very helpful in painting. I absolutely believe that this is common, but the problem is that not many people know about it.

  36. #36 Tirzah
    December 2, 2009

    I heard it. I suppose that I have different types of synesthesia as well, although hearing this was unexpected. It was like someone breathing (I put the video on repeat).

  37. #37 Morgan
    March 11, 2010

    It was like hearing a geiger counter, or taping fingernails rapidly on a hard surface and seemed to come twords me when the dots were going out, and away when the dots were going in.

  38. #38 Franceska
    April 27, 2010

    I’ve got it the other way around. I see colors and shapes when I hear sounds. But when I looked at that video I just heard a boring up and down sort of thing which wasn’t a sound in my ears but in my head. a pattern that was directional. Its hard to explain and I don’t think that makes any sense.

  39. #39 Kelli
    May 25, 2010

    This hurts to watch. Ow!

  40. #40 sikiş
    May 26, 2010

    Includes an udder disaster of a last line: “Milking these ideas as much as possible should prove to be very insightful from both theoretical and practical perspectives.

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