What is the most annoying sound ever? Finger nails on a chalk board? Nope...

Scientists studying the brain‘s reaction to sound have determined the piercing screech of a knife against a glass bottle to be the human ear’s worst nightmare.

A research team at the University of Newcastle in Australia examined brain activity in a group of volunteers, who listened to 74 recorded sounds under an MRI machine and ranked each experience.

The top 5 most irritating sounds are:

#5.)  Nails on a chalkboard.

#4.)  Rubbing a ruler against a glass bottle.

#3.)  Writing on a chalkboard with chalk.

#2.)  Dragging a fork across glass.

#1.)  Rubbing a knife against a glass bottle.

Listen below (if you dare!) and tell us what sound is the most irritating to you! The most irritating to me? No doubt, ALL OF THEM!