Hear bumps in the night? You’ve got exploding head syndrome!

AS you drift off at night do you ever hear a door slam or a loud shout, only to find that the rest of the house is still sound asleep?

Then you could be suffering from ‘exploding head syndrome’, psychologists say.

The condition – where imaginary noises wake you as you drop off to sleep – affects between 10 and 20 per cent of people, according to a study.

And the noises can vary from explosions to a crack of lightning, fireworks or even gunshots.

The noises usually start suddenly and last for a few seconds. Some people also experience visual disturbances, such as lightning or flashes.

The condition stops people from sleeping and can lead to psychological problems because sufferers sometimes believe they are having a seizure or are being attacked, experts said.

For some, the condition is so bad that it can have a significant impact on their lives.

It had been believed the condition only affected people over the age of 50, but Dr Brian Sharpless, of Washington State University, says his research proves it often occurs in young people.

He interviewed 211 students, of whom a fifth had experienced the problem at least once.

Dr Sharpless said that the disorder happens as the brain is shutting down.

When the brain goes to sleep, it shuts down like a computer, with motor, sound and visual brain cells turning off in stages.

But instead of shutting down properly, the brain cells respon- sible for sound are thought to fire all at once, creating a blast of energy that the brain interprets as a loud noise.

Dr Sharpless said: ‘That’s why you get these crazy loud noises that you can’t explain, and they’re not actual noises in your environment.’

He also found more than a third of students who had exploding head syndrome also experienced isolated sleep paralysis, a frightening experience in which one cannot move or speak when waking up.

People with this condition will literally dream with their eyes wide open, he said.

Dr Sharpless added that sufferers ‘may think they’re going crazy and they don’t know that a good chunk of the population has had the exact same thing’. While exploding head syndrome might sound funny, Dr Sharpless said it could actually be extremely frightening.

It can lead to sleeping problems and worse: An attack may cause temporary tachycardia – a faster heart rate than normal - and palpitations.

In the longer term, it can also lead to panic disorder, depression and catastrophising, a condition in which patients misinterpret symptoms as signs of more serious conditions, such as a stroke. Dr Sharpless criticised the lack of treatment for exploding head syndrome and sleep paralysis, although researchers are carrying out tests on drugs that may help.

‘One of the drugs they gave for exploding head syndrome actually didn’t make the noises go away,’ he said. ‘It just turned the volume down.’

Many people are simply relieved to get a diagnosis and learn that they are not alone.

‘There’s the possibility that just being able to recognize it and not be afraid of it can make it better,’ Dr Sharpless said.

The research was published online in the journal Sleep Medicine Reviews.

‘They think they are going crazy’