Can you "hear" flashes of light? Do you have synesthesia? Take a test


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My mother had measles encephalitis at 13 and started seeing sound-- flashes of colored light. It was 1964, and they diagnosed her as schizophrenic and kept her in the psych ward for months because of these “hallucinations.” I still can’t believe none of the doctors thought “Gee, maybe a brain infection has lasting neurological effects that are distinct from mental illness.”


That huge flashbulb in the illustrative GIF actually makes noise when it flashes, so it’s not a good illustrator of this phenomenon. I can imagine the sound just by watching the GIF. Heck, I think I have a box of those in the garage. Time for a test…


Have you verified that these automaticly flashing images will not trigger seizures in some people?


I really didn’t know how to answer this. I didn’t experience the video as inducing sound, but I did experience a voice in my head mimicking some of the sounds that the images would have made. Like, if you watched the video next to a kid who went, “bang!” every time something got hit, the video would indirectly induce audio experience, but you’d say it didn’t. But if that kid is inside your brain, I just don’t know what to say except I don’t think that’s what they mean.


My brain usually makes up a faint soundtrack to go along with some highly rhythmic, looping sorts of visual inputs. Similar to a semi-conscious finger tapping or other such response to music.

Doesn’t everyone do that? I’ve never though of it as strong or trippy enough to be considered actual synesthesia, but what do I know.

I do more strongly experience the opposite (?) effect sometimes: when I hear a sudden noise right on the verge of falling sleep, there’s the sensation an equally sudden bright flash over the usual closed-eye darkness.


Please speak up, I can barely see you!


This one always does it for me:


I didn’t really get anything from the videos I saw on the test, but that one I think I do experience I kind of “thud” when it lands. Maybe the images they were showing weren’t loud enough.


They don’t bother much with a precise definition of auditory sensations, do they? I too get your “brain foley” experience, but it’s more of a voluntary thing so I don’t think it’s quite the same.

I do work quite often with actually putting sound to silent video, so I might be weirdly biased one way or another.


I’d wager that dramatically screws up the results.


Hmmm - I think 100 ug of some nice low pH material would help my synesthesia score immensely.



I keep boxes of Press 25’s around to feed my Speed Graphic, and they make a definitely audible noise when triggered. I am always amused when these are used in movies, because the sound is often greatly magnified as an effect.


I think that’s part of the point. Many of the videos are things that actually make familiar sounds, many aren’t. They may be testing out how much synesthesia is connected to the imagination, or are trying to weed out those who mistake such imaginings from actual synesthesia.
I still marked zero for all but one of the videos as i could tell that i was imagining imagining the sounds. For example, with a bounced tennis ball video i thought the word “plok”, not the actual sound that that word is imitating.


This is similar to the only one that i didn’t report a zero on (i reported a one, this would be three). Like @Humbabella, i can “hear” a distinct thunk on this one, just as in a roller coaster ride video in the test i could “hear” the rattling of the car along the track.


The Epilepsy Foundation’s website says this: “Generally, flashing lights most likely to trigger seizures are between the frequency of 5 to 30 flashes per second (Hertz).”

The flashing lights in the GIF don’t seem to fall into that range.


When I was young I used to cover my eyes for fireworks. My sister has number-color synasthesia, and I have no idea how my brother is wired, but I suspect his polarity is reversed.

I can ‘hear’ the thud and several of the wires making that wire flexing noise. Is it strange that I can imagine that vividly?

lots of this:


I guess that’s why LED lighting designers have never been pressed to do anything about that 50/60 Hz flashing… For someone who has something similar to nystagmus this is the general feeling I get when looking at LED pre-lit Christmas trees (especially the blue ones).


I’m not sure if I “hear” something inasmuch as I “feel” something. It is like someone in another house or apartment amping up the bass on the stereo. You might not be able to hear it but you can feel it.