Research has shown people who find sounds such as chewing, heavy breathing or tapping of a pen unbearable have a brain abnormality.

The condition, known as misophonia, causes people to have an intense emotional reaction to certain 'trigger' sounds.

Medical opinion has been sceptical in the past as to whether misophonia is a genuine condition, but now researchers at Newcastle University have reported finding a difference in the frontal lobe of sufferers.

In an report published in the journal Current Biology, scientists said scans of misophobia sufferers found changes in the brain activity when a trigger sound was heard.

Researchers found a difference in the "emotional control mechanism" that causes their brains to go into overdrive on hearing trigger sounds.

Dr Sukhbinder Kumar, from the Institute of Neuroscience at Newcastle University, said: "This study demonstrates the critical brain changes as further evidence to convince a sceptical medical community that this is a genuine disorder."

Tim Griffiths, Professor of Cognitive Neurology at Newcastle University and UCL, said: ""I was part of the sceptical community myself until we saw patients in the clinic and understood how strikingly similar the features are."

One misophonia sufferer said her GP laughed when she told him about her symptoms.

Olana Tansley-Hancock, 29, from Ashford in Kent, was eight years old when family meals became unbearable for her.

She said: "The noise of my family eating forced me to retreat to my own bedroom for meals.

"I can only describe it as a feeling of wanting to punch people in the face when I heard the noise of them eating - and anyone who knows me will say that doesn't sound like me."