Fingernails on a chalkboard? Nope. Rubbing a balloon? Uh-uh. Screeching tires? Not even. Researchers at the University of Newcastle in the U.K. have brutalised the eardrums of 16 subjects to try and find out what sound agitates humans the most.

After playing the participants 74 different sounds while they were trapped inside an MRI – let's be honest, one of the worst ways to spend an afternoon imaginable – the scientists deduced that it was the sound of a sharp knife on glass that most irritates our amygdala, the primitive part of our brain, making us want to run screaming in the other direction. Perhaps it mimics the sound of a pterodactyl as it swooped down to pick up our ancestors. Perhaps it's just awful. Either way, the real winner is SCIENCE.