text: A mother who one day woke up believing she was a teenager after losing 17 years of memory overnight is set to detail her remarkable experience in a new book. In 2008, Naomi Jacobs - then aged 32 - woke up terrified of her son, in totally unrecognisable surroundings and thought she was 15 years old. Overnight, she had been struck with Transient Global Amnesia, a form of memory loss brought on by stress that had wiped the 'episodic' part of her memory. Naomi Jacobs was 32 when she woke up one morning having lost her memory of the past 17 years of her life . The last thing she could remember was falling asleep in her bunk bed as a schoolgirl, dreaming about a boy she had a crush on. She thought it was 1992, John Major was prime minister and she was about to sit her GCSEs. Mobile phones were still the size of a house brick, the internet a mystery - and her 10-year-old son was a stranger. But Miss Jacobs told the BBC it was when her son bounded up to her yelling 'mum' that she succumbed to 'total shock'. She said: 'Everything from fear to joy from seeing this child that I didn't have any memory of giving birth to, but knew undoubtedly that he was mine because he looked so much like me, to terror of having the responsibility of this small child. 'I was convinced that I was going to fall asleep again that night and wake up in 1992. It wasn't real to me what was happening.' Miss Jacobs pictured as a 15-year-old - the age she believed she was when she woke up one morning when struck by amnesia in her early 30s . Miss Jacobs had Transient Global Amnesia, a form of memory loss brought on by stress. It affects five in 100,000 people in Britain, rising to 23 in 100,000 in the over 50s. Before her attack, Miss Jacobs, of Manchester, was worrying about a homeopathy business she ran. She was studying for a psychology degree and had her final exams approaching, and had recently split up with the father of her child. The condition caused the 'episodic' part of her memory to shut down, meaning she had lost all her emotional memories. But her semantic memory was still intact, meaning she could remember things she had repeated over time such as how to drive and phone numbers she had regularly dialled. Miss Jacobs has previously described lying awake at night and crying as she desperately tried to make sense of her life and longed to be back at school. She is now set to detail how she began to understand who she was in a new book, titled Forgotten Girl. The book reveals how she went about piecing her life back together using her personal diaries and those close to her. There is no specific treatment for Transient Global Amnesia other than support and reassurance from family and loved ones. Fortunately, Miss Jacobs had this support, and after eight weeks her memory began to return to normal. Transient global amnesia (TGA) is a type of amnesia involving the sudden, temporary disturbance in an otherwise healthy person's memory. The leading hypotheses are some form of epileptic event, a problem with blood circulation around, to or from the brain, or some kind of migraine-like phenomenon. TGA attacks are associated with some form of precipitating event in at least one-third of cases. In females, this event is more often of a strong emotional character; in males, it is more often related to some physical exertion. The most commonly cited precipitating events include sexual intercourse, swimming in cold water or enduring other temperature changes, and emotionally traumatic or stressful events. TGA is most common in people between age 56 and 75, with the average age of a person experiencing TGA being approximately 62.
target: Naomi Jacobs woke up one morning believing she was 15 years old .
  She was in fact a 32-year-old mother of one running her own business .
  Miss Jacobs had been struck by what is called Transient Global Amnesia .
  The condition had wiped away the past 17 years of her memory overnight .
  She admits succumbing to 'total shock' when her son called her 'mum'