Some days all I want to do is give up the constant, exhausting struggle and stop trying to be normal. But I can't. It's not in me to walk away from a fight. I'll keep fighting and telling my story. Before I forget.

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. Twenty years later she is still thriving, still working hard to rewire her brain even as it loses its function. The unusually slow progress of her condition puts Christine in a unique position to describe the lived experience of dementia, a condition affecting tens of millions of people worldwide.

In this revealing memoir, she looks back on her life in an effort to understand how her brain - once her greatest asset, now her greatest challenge - works now. She shares what it's like to start grasping for words that used to come easily. To be exhausted from visiting a new place. To suddenly realise you don't remember how to drive. To challenge, every day, the stereotype of the 'empty shell'.

Brave and inspiring, this is Christine's legacy for people with dementia and those who care about them.

'Christine teaches us that we are more than what our brains are capable of remembering, that while we can still breathe and love, we all have something important to contribute to this world.' Lisa Genova, author of bestseller Still Alice