Researchers at Newcastle University proved that unpleasant sounds provoke a much stronger response in the human brain than pleasant ones.
Volunteers listened to 74 sounds, and their brain activity was measured with an MRI scanner while they were exposed to them, recording their reactions.
Annoying screeching sounds are processed by the brain's auditory cortex, as are all sounds, but also activate the amygdala, a primitive brain region responsible for reflexes and emotions.
Dr. Sukhbinder Kumar, initiator of the study, described his findings in the Journal of Neuroscience.
"It appears there is something very primitive kicking in. It’s a possible distress signal from the amygdala to the auditory cortex," he says, suggesting that the noises we hear have very much to do with the feeling of danger we sometimes perceive.
The disturbing sound of a knife on a bottle was the unlikely winner for most annoying ever, while the noise of bubbling water was among the most soothing and relaxing.
Without further ado, check out the top 5 least bearable sounds, as related by the Telegraph.