Top 10 Most Horrible Sounds

Acoustic research shows that frequencies between 2,000 and 4,000 Hz – exactly the range of nails on a chalkboard – overstimulate the human ear canal the most.

For people with misophonia, the sound of fellow diners eating or slurping triggers an acute fight-or-flight response in the brain.

Loud verbal aggression triggers an immediate release of cortisol and adrenaline in everyone in the same room.

The piercing, sky-high squeal when a microphone picks up its own amplified signal sends audiences' hands to their ears en masse.

Retching activates mirror neurons in our brain, so many people immediately feel nauseous themselves when they hear the sound.

When steel train wheels grind against steel rails, a deafening metal-on-metal screech arises that carries for kilometers.

The grating, squeaky sound of Styrofoam blocks in a cardboard box triggers the same physical disgust in many people as a chalkboard.

The grinding sound of enamel rubbing together with brute jaw force sounds like stones being crushed.

A ground loop or bad capacitor can cause a persistent 50 Hz hum that slowly destroys your concentration in the background.

Without the right technique, string instruments and beginning wind players produce shrill discords that cut right through you.