Fingernails on a blackboard

Why does this feel so bad? (when you hear it) & it can’t possibly help from an evolution angle either. So why?

Actually, I think there could be an evolutionary angle.

When I hear, or even think of, fingernails scratching across a blackboard, I get goosebumps and the little hairs on my arm etc stand on end. Had I a long coat of hair or fur, I would look bigger with my hair standing on end.

So, if you want to consider that the screeching sound that a pouncing predator makes, resembles the sound of fingernails on a blackboard, you can see a remotely possible connection. When a hair covered organism hears such sounds, its hair stands on end so as to make itself look bigger and thus less attractive to a predator. Possibly, the ‘hair-on-end’ arrangement may also work to absorb bites better than simply having the hair matted down.

All of this is speculation.

Thanks,doc-QtM,I think, said I’d see you here. Of course, a sympathetic nervous reaction. Only been here a few days, & I forgot to check old threads 1st. This board has been around so long, hard to believe this wasn’t asked before.

Here’s Cecil’s take on it. This makes (a bit) more sense than my speculation.

And, welcome to the SDMB!

Thank you. Read & appreciated. & appreciate politeness too. BTW, last week my secretary had a terrible case of overuse caused laryngitis. Her voice made me feel that way. I told her either to go home or whisper.

Greetings as well.

This is one of those things that I just can’t relate to. The sound of fingernails on a blackboard has never bothered me beyond the fact that it just sounds a bit annoying. I wonder how common it is for people to actually be bothered by the sound?

The blackboard doesn’t bug me either however I cannot stand the sound of metal on metal or anything like that.

My problem comes up ALOT more than the chalkbaord thing…think anytime you are eating with china plates and silverware.

I have to eat on either paper plates or plastic or I cannot eat.

Man just typing this gives me goosebumps.

A bit strange, but long ago a friend and I were playing in a swimming pool trying to see how long we could stay underwater. We brought in various large heavy objects to help hold us down, including a length of thick metal chain. For some reason the ‘sound’ of the links of the chain clanking together, underwater, made the WEIRDEST feeling in the back of our necks. Similar to the blackboard thing but like 10x as strong. Haven’t tried it recently, wonder if it was just ‘one of those things’.

I have no problems with nails on a blackboard, or metal knives on plates, but I do freak out with goose bumps even at the thought of a blunt pencil on dry paper - the dull scraping of dry on dry. Many types of pen also produce this killer textured noise which so freaks me out. This is a particularly grating as I work in a drawing office where I constantly have to leave the room if someone is colouring in.

So, follow-up question:
Does every person have a specific frequency of noise or scraping which rankles their nerves?
Is there a way to reduce your sensitivity to certain nerve-effecting noises?

Not sure about 1st question-people have 1 to 4 wisdom teeth- vestigia too. I think “flooding” ie, constant exposure to obnoxious stimuli might help reduce irritation caused by it. Trouble is, too annoying to try it.

In Cecil’s answer, no explanation of why a reaction would remain “vestigal” tens of thousands of years after it had any practical use. People with high stress reactions to non-dangerous situations would seem to be selected against in natural selection, don’t you think?

I’m like that with chalkboards but also with fingernails acorss paper/cardboard. That’s almost worse.