Why Do We Hate The Sound Of Nails On A Chalkboard?
Nails on a chalkboard, wailing babies, and forks scratching across plates are all intensely unpleasant sounds. But why do we cringe when we hear them? A 2012 study in the "Journal of Neuroscience" subjected participants to 74 different sounds, and found that the most universally reviled ones fell in a frequency range between 2,000 and 5,000 hertz. (The most awful sound? According to the study, a knife on a bottle won out over nails on a blackboard.) There are multiple theories as to why we feel pained by these noises. Some think it's an evolutionary response to sounds that are similar to distress calls, whereas others chalk it up to the anatomy of our ears.
Key Facts In This Video
Human ears are extra sensitive to a particular range of pitches, and there are several theories as to where that sensitivity comes from. (0:45)
A 2012 study found that cringe-inducing sounds activate an interaction between the brain's auditory cortex and amygdala. (3:09)
Some researchers think that the anatomy of the human ear amplifies certain frequencies, sometimes to the point of causing pain. (3:47)