Quote:...Scientists from Newcastle University have drawn up a league table of the least pleasant sounds we may encounter as part of everyday life – albeit a slightly old-fashioned life as the top five include the rasp of chalk on a blackboard.

Working with 13 volunteers, they tested reactions to 74 different noises both in outward response and more closely via small changes in the brain.

The results are published in the latest issue of the Journal of Neuroscience and show, among other things, that acoustically anything in the frequency range of around 2,000 to 5,000 Hz was found to be unpleasant. The author of the paper, Dr Sukhbinder Kumar, is not surprised. He says:

This is the frequency range where our ears are most sensitive. Although there's still much debate as to why our ears are most sensitive in this range, it does include sounds of screams which we find intrinsically unpleasant....

http://www.guardian.co.uk/uk/the-northerner/2012/oct/10/newcastle-university-scientists-brain-unpleasant-sounds-reaction?newsfeed=true