Fingernails on a blackboard. Why does the very phrase send chills down one’s back? The question has annoyed scientists for at least 2,300 years. Aristotle mentioned “hard sounds”, but didn’t try very hard to explain them.
In the mid-1980s, three scientists subjected volunteers to a battery of electronically synthesised nails-on-blackboard screeching. D Lynn Halpern, Randolph Blake and James Hillenbrand, at Northwestern University in Evanston, Illinois, published details in the journal Perception and Psychophysics. They called their study “Psychoacoustics of a Chilling Sound“.
So begins this week’s Improbable Research column in The Guardian.