You're listening to the BBC World Service and this is Solving Alzheimer's.

This week, the world's most challenging disease.

Or in the words of a 12 year old girl in South Korea.

It's the scariest disease in the world.

Scary and in some places utterly horrifying.

What horrified me is a person being stoned and everybody joins in the stoning. you know, it's a mob.

All because they were talking to themselves, they were dishevelled,

so they must be a mad man.

I could see. That person had the main check.

My grandmother had Alzheimer's and I saw this disease up close and personal and I watched it systematically disassemble the brilliant

wonderful woman who was my grandmother.

That is legitimately terrifying.

My expert for this program.

Hi, my name is Lisa Genova.

I'm a neuroscientist and author.

I write about people living with neurological diseases and disorders who tend to be ignored, feared, and misunderstood.

This disease is terrifying and embarrassing and confusing and it would be much easier not to look at this and to pretend it doesn't exist and to hope it doesn't affect us.

And yet the very real statistics was actually happening now and this is going to get worse

is that right now at 85, one in three people have Alzheimer's and that number is fast approaching one and two.

Dementia describes a number of degenerative brain conditions

but the most common one is Alzheimer's disease, which starts with short-term

memory loss and confusion.

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