What is it about nails on a chalkboard that make just about everyone cringe? Any scientific reason?

The frequency of the sound stimulates the nervous system causing an involuntary muscular reaction at the base of the neck. This has the effect of causing you to shudder; making your spine tingle; putting your teeth on edge, or a combination of all three.What is it about nails on a chalkboard that make just about everyone cringe? Any scientific reason?
Good question. i am adding this to my watch list.What is it about nails on a chalkboard that make just about everyone cringe? Any scientific reason?
The sound is definitely unpleasant- screechy like a bird of prey or a trapped animal. It could be a natural instinct for humans to flinch when they hear these noises.





Another reason could be empathy with the scratcher. The act of scratching a slate chalkboard is rough on the fingernails, and often causes irritation of the nerves. Anyone who has ever raked his hands across a blackboard can easily identify with this painful sensation.
It is just the sound
It's just the sound. High pitched, screeching sound.
NO CLUE
I agree with mbunston the high frequency and high pitched screech is more noticeable to people the age of 12-20.
My scientific view. The contact between chalk and the chalkboard produces a vibration the very same efect that you experiment when you suddenly step on the breaks of your car and the wheels over the pavement produce that particular high sound. It is vibration of one of the tow elements that produces sound and the one you quote particularly high has to have an answer in the length of the part of the chalk from the fingers till it reaches the chalkboard and the angle it is performing with that surface, also the kind of surface and the material of the chalk. My humble view, at least that is waht i am planing to tell my son in case he inquiries me. Greetings