What is it like to look at your children or husband and not recognise them? One woman is fighting to overcome the disturbing effects of a virus that struck entirely without warning.
When Claire looks into the eyes of her children, it is a moment of profound confusion.
The 45-year-old mother of four suffers from prosopagnosia, sometimes known as face blindness. She cannot recognise the faces of her children, her husband or even herself, after a virus struck little more than two years ago, causing inflammation in her brain and permanently harming the temporal lobe.
The loss of key parts of Claire's memory has proved traumatic and has profoundly disrupted the sort of relationships most of us take for granted. Every day is a battle.
"I find it very difficult just living my everyday life. I go up to the village or out to the school and they say hello to me, how are you. I haven't got a clue who they are or how I know them," Claire says.
But given the correct trigger, she can sometimes put a name to a face, says clinical neuropsychologist Bonnie-Kate Dewar, who is helping Claire with the condition.
"Claire may see someone in her village and not be able to recognise them from their face," explains Ms Dewar. "But when they say 'oh yes but I'm so-and-so and I live here', sometimes that may actually put the connection back together and she's able to recognise and know that person."
Yet prompting doesn't always work - suggesting that, for some faces, the knowledge of that person has been wholly lost, or sits in a deeper recess of the brain.
"What I really need is their whole identity not just their name," says Claire. "They might say to me what their name is and it still means nothing to me."
At home with her children and husband
Although scientists can describe Claire's condition, they are powerless to cure her.
One problem that looms large is that researchers are still arguing about how memory works on even the most basic level - such as what happens when we create or recall a memory.
Some believe memories are stored inside our brain cells, others that they are encoded in the connections between them. But how our memories stay put, and why things are forgotten, are burning issues.
A lot of what we think of as lost memories are still in the brain somewhere. We might struggle to recall the name of the person we met at the office party last week but find it much easier to select the right answer from a multiple choice quiz down the pub. In effect we forget, until something jogs our memory.
But Claire's virus means whole areas of memory have been wiped or are inaccessible. And her condition underlines how crucial memory is to our everyday lives, says Ms Dewar.
"So much of our relationships are dependent on our memories and our history with people," says Ms Dewar, "and with Claire it has had a particularly difficult impact because this is where her difficulty lies."
Identity, says Claire, means more than just a name.
"It means a whole person, how we know each other, how we shared times, knowledge, understanding, caring. It's very meaningful. We just take it for granted if we're given a name that we think 'oh yes you're the person' and you don't even have to think it through but that's just gone from me."
With Ms Dewar's help, Claire is working on compensatory memory strategies; working around the damaged parts of her brain using techniques such as learning and problem solving.
How does it work?
"Pat, one of [Claire's] friends delivers eggs and Pat has a bright red beard so she is able to use his beard in a problem-solving way to say well this is who he might be," says Ms Dewar. "She also uses context to identify her family members. When one of her sons is playing football, she looks at the number on his back and is able to follow him that way."
Home videos of Claire's family have allowed her to access some of her past life which she has lost. But that can only partially fill small gaps in the entire history of her family life, bringing up four children.
Claire's husband, Ed, says he's now well used to raking over past family memories in a bid to help his wife.
RELATED BRAIN DISORDERS
Visual aphasia: Problems recognising text
Mirror agnosia: Objects in one side of field of vision cannot be recognised
Somatosensory agnosia: Problems recognising things by touch
"You do it to make decisions, to go back and do things you enjoyed before. It marks out how your relationship grows," he says.
Another aid is what Claire calls her friendship book.
"I've made this special book and Bonnie-Kate has helped me to write down the name of somebody, their family, where they live, special things, where we met, the things in life that we shared, that mean we know each other. So their identity out of nothing is there and once I've got it written down I can re-use it."
Claire describes it as "like finding myself".
"We went camping," says Claire reading from the friendship book, "and had a gale in the night and flooding and they lost their tent and ended up crammed in the car. Lovely memories like that I've put in the book."
"Caroline isn't just a name. She is here in my friendship book and we belong to each other as friends and that whole feeling, meaningfulness of identity, not just of my friend but of myself and how we fit together has been so drastically lost that I can't tell you how important it has been to write these things down about people and share special memories while we've been doing it.
Me And My Memory is on Radio 4 on Wednesday 26 July at 0930 BST and is part of Radio 4's Memory Season.
Add your comments on this story, using the form below.
I suffered a head injury several years ago, resulting in memory problems. (Some one might say something, or an event might occur, and within moments I would have forgotten about it, unless I concentrated soley on that event).
Different people with similar head/brain injuries seem to demonstrate different symptoms, suggesting that the workings of the brain is complex. It used to be thought that the brain was unlike the rest of the body, in that it could not repair itself, but apparently it has been recently found that brain cell regeneration does occur albeit on a slower scale than the rest of the body.
My memory, although still not perfect, is much improved, allowing me to function normally now. It's taken a long time for me, all I can say is I feel for Claire and her family, and hope that Claire's problem also resolves itself with time.
Tony Bradley, Plymouth UK
I have had moderate prosopagnosia all my life. So far as I know I was just born with it. The most difficult thing for me is when I can't recognise people in social situations, so I often seem to be ignoring people I've already met. People often think I'm stuck-up and rude, but I'm not - I just truly don't know who they are. By the way, I don't mind being called "prosopagnosic", but I really hate the term "face blindness": I'm not blind to faces, I just can't remember them.
I also have this condition though to a far lesser degree than Claire. Prosopagnosia is often referred to as "face blindness" to express the parallels with dyslexia and it can be a very isolating condition. Meeting people in crowded places or the first weeks in a new job are particularly confusing but I have learned learning to recognise people by how they dress, how they walk and the sound of their voice rather than by recognising their faces but I still walk past people I know in the street without recognising them until they speak. I can only imagine how devastating this would be for a mother who cannot recognise her own children.
I suffer from a milder form of prosopagnosia and have done from birth, although I've only been diagnosed in the last year. It was only recently I discovered that my inability to recognize faces wasn't normal, It's always amazed me how other people can recognize characters in films, or even tell who someone is from a passport photograph. For me, it's something I've always had, so I don't find it effects my day-to-day life, although I'd be hard pushed to recognize my wife if I met her unexpectedly.
A few years ago a new, young library assistant joined the staff of the busy academic library where I work. With confidentiality at interviews, we were only told she'd had an accident in the past which left her with a slight limp. It was my job to train her, and the automated library system requires staff to remember the processes, such as warnings about fines, overdue books, recalled loans etc. and to deal with them accordingly.
Every day to this girl was like her first day at work. I appreciate that some people have problems with computers so was patient with her and explained repeatedly how you deal with the messages that accompany most transactions, but it wasn't until, after several weeks, I realised that not only was she not picking up the work at all, but she didn't know me or my name and that each day for her was like meeting a new trainer!
I tested her gently and realised that out of a staff of 15 who all work together, the only person she recognised and the only name she knew was that of the one male on the staff. To some extent she tried to cover up her difficulties and when we tried to talk to her about it she was aggressive. Sad, and sad too that we couldn¿t accommodate her or understand that she had been very damaged by her accident and couldn¿t function in a place like ours.
There's a really interesting account of another case of prosopagnosia, as well as other related conditions, in Oliver Sacks' excellent book "The Man Who Mistook his Wife for a Hat" - a fascinating read.
Adrian Horsewood, London, UK
I read this very moving and interesting story whilst at work. It really outlines how special each day is and how wonderfully we are created.I do hope that Claire's memory will be someday restored and pray that her family have the strength and support needed to help them adjust to their new situation. Jade
Miss Jade Small, Sutton Greater London England
Whilst my experience was only shortlived, it gives me some slight understanding og her fear. For a period of approx. 3 days I lost the power of speech. My brain knew what I wanted to say, but either my words did not come out at all or it came out as complete nonsense. I hope that in the fullness of time this lady's life will return to some form of normallty.
Colleen P.M. Edwardsl, Ilkeston, Derbyshire
I am a congenital prosopagnosic, recently tested at the Institute of Cognitive Neuroscience in London and found to be 5 standard deviations adrift of normal at face recognition (about 1 in a million). I've had 44 years to devise compensatory processes (mostly unconsciously as CPs are rarely diagnosed - people just think we're really dozy, unobservant and rude not to recognise them). In fact we use a tremendous amount of brainpower trying to recognise people, dredging through data we have had to consciously memorise because the automated trigger of the face does not work for us.
Meetings at work can be exhausting! But at least I can remember people once I know who they are. I have every sympathy with Claire, who will have an even harder time because her brain will have been using faces as the "key field" in her personal database, and now she's lost the key field she obviously can't access the other data she's stored for each person.
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