Horrible noises in Radio 4 test

An 18-year-old amateur scientist is launching a national experiment to test our reactions to horrible noises. Izzy Thomlinson, from Shropshire, wants to find out why some people are more sensitive than others to sounds like scraping cutlery and squeaky balloons. She is a finalist in So You Want to Be a Scientist?, BBC Radio 4's search for the UK's best amateur researcher. In January, Izzy was selected as one of four finalists by a panel of judges led by Nobel laureate Sir Paul Nurse. The finalists have been teamed up with a professional scientist to help turn their ideas into a real science experiments, as part of Radio 4's weekly science programme Material World. A-level student Izzy Thomlinson applied to investigate why we hate particular noises, and how this varies with age. Now she has designed an interactive experiment to test people's reactions. "I'm particularly interested in testing noises that people find horrible, but you can't think of a logical reason why," Izzy explains. Suggestions from Radio 4 listeners have included tearing polystyrene, squeaky felt tip pens and rustling carrier bags. Together with her mentor, Prof Trevor Cox from Salford University, they want to find out whether age, gender and personality affect our sensitivity to these noises. Acoustic engineer Prof Cox says the jury is out as to why people react so strongly to strange sounds, like nails scraping down a blackboard. In a previous study, he found that the most irritating noise in the world is the sound of someone vomiting. This provokes a reaction of disgust, which alerts us to the threat of disease. But why the sound of cutlery scraping against a plate makes some people shudder is still a mystery. "Our response to this sound is an enigma, what would be the evolutionary or cultural reason for responding so strongly to scraping sounds? It seems to serve no purpose. We're not going to be able to answer this directly from our research, but hopefully Izzy will be able to shed a little more light on what is going on." Izzy will be updating her research diary on Facebook, and the test can be taken here. You can hear more about the experiment on this afternoon's Material World at 16:30 BST.