'The simple question that revealed I had dementia - at just 46.'

When she was just 46, Christine Bryden – science advisor to the prime minister and single mother of three daughters – was diagnosed with younger-onset dementia. Doctors told her to get her affairs in order as she would soon be incapable of doing so. In her memoir, Christine writes about the moment she was diagnosed, and how she has rewired her brain since then.

My mother closed her eyes, held her pen aloft, and made circles in the air. Then she brought it down onto the page of her open Good Housekeeping magazine, already pockmarked all over. Her ballpoint was running low on ink. She squinted down at the mark she’d made on the page.

‘P,’ she said.

I looked at her, my own pencil poised, scrap of paper in front of me. She glanced at the clock on the mantelpiece.

‘Go!’

And we were off. We were playing a game we called Town, Country, Sea, River. We had to write down as many of them that begin with the letter ‘p’ as we could, then girls’ names, boys’ names, animals and plants, in five minutes. Mum was competitive. She excelled at this game, and although I was 10 and she 38, she pushed me to beat her, and never conceded.

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As a result, I’d scour the old atlas in between games, memorising the names of obscure towns, countries and rivers. English was Mum’s second language – maybe she enjoyed the challenge of remembering the English names for things.

Memory is one of the cognitive processes I have great difficulty with now, so I treasure this snapshot of my childhood. It reminds me of a time in my life when my brain was growing, stretching, forging new pathways, as opposed to now, when it is on a gradual decline.

It reminds me of precious time with my brilliant mother, who has since died. And I treasure it simply because it is a memory, and I love and guard the memories I have left.

Many years later, in a small room in a research centre on the other side of the world, I was sitting with a neuropsychologist. I was to do a battery of tests, the scores of which, combined with an MRI scan I would be having that afternoon, would be given to a professor who would try to diagnose my type of dementia.

The neuropsychologist asked me to name as many objects as I could that begin with the letter ‘s’ – not including any proper nouns. I started to tell her about the game I had played with my mother as a child. She smiled politely, but cut me off. She just wanted to get on with the test. So I started thinking. Nothing came. Slowly, very slowly, I came up with a few concrete objects that I could see around me in the room and out the window. Stapler, seat, sky. Then I thought some more.

‘Ah . . . stables!’ I exclaimed triumphantly. ‘Step! Um . . .’

Then inspiration faded. Nothing more came. I felt so disappointed with my failure, remembering how good I’d been at this game when I was a child. But a thought occurs to me now ... how well would I do at this test, how well would I cope with life, with dementia, if Mum hadn’t pushed me to achieve and remember so much when I was a child?

This is my life story – but it’s also, in a sense, a biography of my brain. When I was a child it was a hungry little brain, absorbing two languages, geographical facts, soaking up as many books as I was allowed to borrow from the library each week. When I was an adolescent it was quite a clever brain, adoring the newfound concept of ‘study’ instead of just winging my exams, poring over my adored textbook: Fieser & Fieser’s Organic Chemistry.

When I was a young woman it was a troubled brain – battling with the puzzling and, at the time, little understood afflictions of anorexia and depression.

As a middle-aged woman my brain came into its own again – I was admired and promoted at work, I was beginning to form meaningful, healthy and life-saving friendships, I was learning how to be a better mother to my three daughters.

And then, a short time after that, my brain developed a form of dementia that should have killed me by now but hasn’t, and although my brain is in a decline and I’ve lost a lot of function, I’ve managed to re-wire it even as it is degenerating and to keep as much of it going as I can.

Dementia itself is not a disease, but a way of describing a progressive decline in memory or other thinking skills. Alzheimer’s disease is the most common cause of dementia, followed by vascular dementia and various types of fronto-temporal dementias.

There are three things to say about my dementia upfront: firstly, there is no doubt as to my diagnosis. There has been a progressive, measurable atrophy (wasting away) of my brain tissue over the past twenty years, shown on CT, PET and MRI scans, and my performance on neuropsychological tests has shown a decline as well.

Secondly, my form of dementia is unusual, because it is progressing very slowly – much slower than average, and despite numerous tests the experts are unable to pinpoint the exact cause of it. Nobody will know for sure what form of dementia I have until they are able to biopsy my brain – and I need every brain cell I have right now, so that moment of truth won’t happen until after I die.

And thirdly, my brain before my dementia was functioning at a very high level – possibly in the top couple of percentiles in the world – so in order to understand how much I’ve lost, you need to understand how much I once had. Whether or not this is a factor in why my dementia is atypical, having this rare, slow-progressing form of the condition has enabled me to make some important contributions that I hope will be helpful for others, all around the world, with dementia.

I’m an expert in the lived experience of dementia. I’ve developed strategies for coping with some of the common difficulties encountered by people with dementia (these strategies are peppered throughout the text, but you’ll also find a comprehensive list in the appendix: ‘Advice’). I speak out for people with dementia, for their rights, for their dignity – and most importantly, for their hope.

A diagnosis of dementia can be crippling. And if you’ve been told by a doctor that you have perhaps five years before you’ll be in a nursing home, and a few years after that before you die, that news has a devastating effect on your motivation to keep trying.

It’s a huge paradigm shift to go from accepting decline to expecting survival. But I am fighting a battle to survive with dementia each day, trying with all my remaining energy to re-wire my brain almost as fast as it is becoming unravelled, diseased and dysfunctional. I believe that a degree of rehabilitation is possible. I want to talk about surviving dementia, of defying dementia, and of thriving with dementia.

And I want to talk about my brain’s journey from my birth to now – because I want to try to understand, and describe, how my life experiences combined to make the woman I am proud to be today: a vibrant, healthy, striving, loved and loving 66-year-old woman with dementia.

This is an extract from Before I Forget: How I Survived a Diagnosis of Younger-Onset Dementia by Christine Bryden, Penguin Books Australia. Find out more about Christine Bryden here

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