Why Is The Sound of Nails On A Chalkboard So Irritating?

If you are like most students, you probably hate the sound of chalk writing on a chalkboard. Come on! Admit it, you would much rather be talking to your friends in the classroom instead of listening to another class lecture. However, there is an even scarier sound that you should be worried about.

You guessed it! The sound of your teacher scratching her nails on the chalkboard.

The mere mention of it can send shivers down one’s body and make one uncomfortable.

Why Does That Screech Make Us Uncomfortable?

Our strong response actually has to do with the structure of our ear. The anatomy of our ears are such that it amplifies the sound in the range of 2kz-4kz, and guess what, the uncomfortable noise of nails scraping on a chalkboard falls directly in this frequency range.

Our brain contains a region called the amygdala, which is responsible for processing our emotions. Therefore, when we hear the sound of nails rubbing on chalkboard, the auditory part of the brain that perceives sound interacts with the amygdala. The amygdala is responsible for the way we cringe our body or cover our ears when we hear this irritating noise.


No wonder students are told to cut their nails when they go to school. Otherwise, they would just try the same trick on the teacher!

Frankly, I don’t think that’s particularly fair.


  1. Wikipedia
  2. Fingernails on a chalkboard garner Vanderbilt psychologist Ig Nobel Prize – Vanderbilt University
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About the Author:

Ashwin Vinod has a B.Tech in Electronics and Communications from APJ Abdul Kalam Technological University, Trivandrum (India). He likes to watch movies, reading fiction novels and surf the internet.

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