Photo: © PA Real Life
Imagine being able to remember every single day of your life, all the way back to when you were a newborn.
Australian woman Rebecca Sharrock is one of only 60 people in the world with a highly superior autobiographical memory (HSAM), also known as hyperthymesia.
Sharrock can recite the entirety of the Harry Potter books, remember every school lesson she had, and recall what she was doing on any given date.
She told Sunday Morning she was diagnosed with autism at 15 and obsessive-compulsive disorder at 16, but did not realise she had HSAM for another five years.
"I did know that I could remember the vast majority of my past experiences," she said.
"I just put that down to my obsessive-compulsive disorder, how I just can't let go of certain feelings or thoughts and just can't drop things."
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On 23 January 2011 - a Sunday morning - her parents called her into the living room of their home to watch a 60 Minutes segment about people with HSAM, she said.
"I turned to my parents and said, 'Why are they calling this amazing? Isn't that normal?'"
That was when they told her they suspected she had HSAM, she said.
Sharrock was diagnosed after undergoing Skype tests with American researchers and flying to California for a brain scan.
Nowadays, she participates in ongoing studies at the University of Brisbane and is in therapy to help her cope with her condition.
Filing memories into mental folders helped her to make sense of them, she said.
For example, she first heard about the Virginia Tech massacre on 16 April 2007, the Boston bombing on 16 April 2013, and the Notre Dame fire on 16 April 2019.
"Even though they're separate memories they do subconsciously link together."
Despite the folders, her mind was "still very chaotic and very cluttered and very busy all or most of the time", she said.
"That does give me many headaches during the day, it does give me a lot of anxiety.
"When I'm trying to fall asleep at night I do get distracted by all of these flashbacks and all of these recollections that just involuntarily flash through my mind."
Therapy was helping her to think of her condition as "a gift, not a curse", she said.
Sharrock said her very first memory was of being a newborn in hospital. She remembered a cotton blanket and a tag being clipped to her ankle.
She also remembered every dream she had ever had.
While therapy had helped, she could still "get lost in a memory" and lose track of the present moment because the sensation was so intense, she said.
"For an hour or a few hours my mind's just stuck in that past event or past experience. Those experiences are very irritating ... they're a very annoying occurrence."