Dr Dev Banjeree explains why somnambulism is so common

Is sleepwalking explained by genetics or environment?

Dr Dev Banjeree explains why 'somnambulism' is so prevalent.

The Consultant Sleep Physician at Birmingham Heartlands Hospital tells BBC Radio 5 live: "We all have a propensity to sleepwalk. It's to do with a part of sleep called slow-wave sleep."

"We've always thought it might run in families," Dr Banjeree tells Nicky Campbell on 5 live Breakfast. "It's always been a mystery."

You can hear other BBC Radio 5 live highlights by visiting the Best Bits section on the website.

5 live Breakfast is broadcast Monday - Friday, 06:00 - 10:00 on BBC Radio 5 live.