Why does hearing sounds like nails on a chalkboard and also imagining them, create such an irritating sensation?
In: Biology
I remember reading the theory that it could be an evolutionary reaction to our primate ancestors’ giant bird predators.
https://www.sciencedaily.com/releases/2006/08/060830005634.htm
(Edit: apparently that wasn’t clear: the sound of a chalkboard or plate scratch was posited to be similar to the screech of giant primate-eating raptors of our primordial ancestors)
People are designed to hear speech, people having conversations, especially well. Because you are so sensitive to the sound of people’s voices you are also really sensitive to any noise at the same frequency. Nails on a chalk board happen to be at the same frequency as people talking, but sound nothing like it. So it really hurts your brain to try and process it, but equally because you are so sensitive to it, you can’t ignore it.
Imagine it’s like the ‘[uncanny valley](https://en.m.wikipedia.org/wiki/Uncanny_valley)’ but for sound.
My biggest trigger is knives and forks screeching against plates. We use plastic plates a lot….
I can tolerate the screech of nails on a chalkboard and it’s super interesting that it’s in the range of human speech. The sound of rubbing a balloon or chewing on a piece of rubber literally makes my brain hurt..just the thought of it makes me squint. Is that also in the same sound range of speech?
I remember reading a scientific article claiming it could be the sound of an ancient predator which our early ancestors feared to death. And so the trauma caused by their voice was implanted in our DNA till now!
Does anyone else get the same irritating sensation over someone folding paper? I have never been able to fold paper my whole life cause of how the thumb goes across the paper and even imagining that feeling brings chills.
I heard a theory that these sounds resemble the scream of primates that indicate danger. We have that atavism from our far ancestors.
I hope it’s okay to post a follow up question but this post made me think of this—I get the same feeling of nails on a chalkboard when I’m eating any sort popsicle with a wooden stick, the feeling of biting on the stick part is the part that bothers me. Just imagining it gives me an uncomfortable feeling. Does this feeling stem from the same frequency thing, or is it something else?
Evolutionary protection to prevent you from chewing rocks or grinding your teeth cuz you used to need your teeth to live.
Hi Everyone,
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That means you can’t share your experience, or that other thing that also causes this for you without also providing an actual explanation as to why. Feel free to put them in child comments, or as a response to this comment.
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