Teenager Ricky Dean lives his life writing lists. He uses boards, notes and his iPhone to relentlessly write down anything and everything he's done or needs to do – because without them, the 19-year-old would be lost.
For Ricky has a rare memory condition, just like Guy Pearce's character in the movie Memento – which means he has no sense of time.
He has to make lists to remind him to do the most basic tasks that we all take for granted, such as eating, brushing his teeth and doing his homework.
Ricky, from Taunton, Somerset, was starved of oxygen when he was born and has no short-term memory.
Doctors say there is no name for his condition and despite his problems he has still gained five GCSEs.
Ricky said: "It can be very difficult at times, but my family and friends are so supportive.
"My mates are constantly having a joke about it, which is good, telling me I borrowed a tenner from them the week before.
"I can never remember if I have or not, so I make a list and if they're just winding me up I get my own back.
"My condition can be so frustrating for people, especially if they don't understand that I just don't remember anything to do with time.
"If I didn't have my lists, telling me to brush my teeth or have lunch, I would be lost.
"The worst thing is missing appointments with friends and forgetting good things, I can't look forward to anything, because I have no concept of time."
As a child, Ricky was diagnosed with autism, but when he was 11 his parents took him for a full memory scan which revealed the full extent of his memory loss.
Until three years ago Ricky rarely left his family home, because he could never remember where he was going, but now he uses lists on his iPhone to keep track of his life.
Mum Nicki, 46, said: "We try to promote independence but tasks such as cooking or running a bath present too much risk, because he wouldn't know whether the oven or bath had been on for five hours or five minutes."
Now Ricky, who took five years of one-on-one tuition to complete his GCSEs, is studying agriculture and horticulture at a specialist unit at Bridgwater College.
Ricky said: "My phone is pretty much my memory now. I use it for everything, just so I can have a normal life."
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