Hey there, it's Ira Flato, and you're listening to Science Friday.

Today on the podcast, a breakthrough and understanding Alzheimer's disease.

This was so surprising that we didn't believe it at first.

In the sub-population of aging individuals who start to show memory loss,

lithium levels significantly dropped in the affected brain regions.

Scientists have been working for decades, as you know, to untangle the mysteries of Alzheimer's disease,

the debilitating brain disorder that over time robs people of their

memories and overall function. New research points to lithium being a possible key to this puzzle.

In a first ever finding, scientists discovered that lithium naturally occurs in the brain

and that taking it away can trigger

Alzheimer's symptoms in mice. So how could this translate to lithium being a treatment for

Alzheimer's in humans? Joining me now as a senior author on that paper, Dr. Bruce Yankner, professor

of genetics and neurology at Harvard Medical School in Boston, Massachusetts.

Welcome to Science Friday. Thank you, Ira. I'm delighted to be here with you.

Now, I know that you have been studying Alzheimer's for decades. What is it about this disorder that has

kept your interest for so many years? Well, first and foremost, it's a disorder of higher cognitive function

in humans, which is arguably what distinguishes our species on this planet. And it is a disorder

that is uniquely human, although we see some changes in other aging mammals. Alzheimer's disease as an entity only occurs in humans.

So I suspected early on that by understanding Alzheimer's, we might be understanding something

very fundamental about the human brain. So let's talk about this new finding involving lithium.

Walk me through what you learned here.

So we came about this in an indirect way.

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