Translator: Jennifer Smithson Reviewer: Tatjana Jevdjic
Good evening everyone. I'm Anwar, from the Speakers Team.
Our next speaker is a graduate of Supélec Paris.
He is currently a researcher at CEA-LETI in Grenoble
and he is here to talk to us about his research
on the interaction between information systems
and biological systems.
Please welcome Rodolphe Héliot.
(Applause)
Thank you, Anwar. Hello everyone. And thank you for coming.
I'm a researcher at LETI in Grenoble and I'm here to talk about neurons.
That video was a great introduction. Excellent. Thanks!
The title is Back and Forth.
I'm going to talk about going back and forth in every sense of the term.
And with a little luck, you'll understand what I mean.
We begin with the story of two feuding families,
the families of Romeo and Juliet.
They really don't get along.
On the one hand, we have the biological world
and on the other, the electronic world.
A certain Montague and a certain Capulet
want to get to know one another.
So every now and then,
in the dead of night,
without telling his family,
because he knows they would not approve,
Romeo sneaks out to see Juliet.
In much the same way,
the electronic world sometimes gives
the biological world a boost.
We can all think of examples
of biological systems supported in some way by electronics.
Take the pacemaker, for example.
At this moment, millions of people throughout the world
are being kept alive by pacemakers.
Lots of research is being done in this and similar fields,
using electronics
to help out biology.
I've had the opportunity to work on such systems
for about 10 years. Here, for example,
helping people with disabilities
regain their mobility.
Today, I'm going to try to expand on this concept
in order to show you some of the interactions
that exist between the biological world
and the electronic world, what we can do with them and,
above all, what lessons can be drawn.
Historically, these two families have failed to understand one another
for one reason: they have no common goal.
The biological world wants to understand what's happening.
A researcher in biology wants to understand the world,
wants to understand the biological world.
On the other hand, the world of electronics
is composed mainly of engineers.
And they have a very different goal:
they want to build.
They build systems,
phones, computers, everything.
These two families were never meant
to be compatible.
Nevertheless, they do interact
in small ways.
And I'm going to try to show you
how that happens.
But to do this, I have to give you some background.
I'm going to talk a little about my job: I'm an architect.
Not that kind of architecture. Sorry.
I design computers.
Their structure is much smaller, much less obvious,
and was pioneered by a man
named John von Neumann
whose work before and after the war
attempted to define how computers work.
In fact, all modern computers,
laptops, cell phones, everything,
work in much the same way.
I won't go into the details, that's not the point.
But I do want to talk a bit about how computers work.
On one side, we have what is known as a processor,
and on the other, we have memory.
When you go to the supermarket to buy a PC, you check out the specs:
1.5 GHz, 4 GB of memory. Great.
These are two of a computer's main components.
And it so happens that, because of the way they are organized,
they spend their time communicating with each other.
The processor asks the memory,
"Can you please send me some data?''
The memory sends it. – "Thanks!"
I'm working. – "OK, I'll send you some data."
"Great. Thanks, I got it."
Basically, what happens is we spend our time
going back and forth between the processor on one side
and the memory on the other.
Imagine a sprinter in the starting blocks,
holding a relay baton.
He has to get
from 0 m to 100 m
as fast as he can, because a computer has to be fast
to relay information, wait 2 seconds, collect another baton
and get from 0 m to 100 m in the other direction.
Then start all over again.
After 5 minutes, the sprinter is exhausted.
Why? Because he expended an enormous amount of energy going back and forth.
What makes this design so great is its versatility.
But it does have one major flaw: it uses a lot of energy.
This is a real problem. And when we see what happens...
Oh, great story!
5 years ago, I was in an electronics department in the States.
I was working on these computers.
One day, I attended a talk given by a professor
in the department of neuroscience. I mentioned neurons before...
This was an old professor; imagine the typical professor,
with a beard, a tattered old vest... that sort of thing.
He had a PhD in neuroscience; he was talking about pain, which by its very nature
has very little to do with my area of expertise.
And he said, "What's great about the brain
is that the same neuron can be used for many things at once."
This sentence refers to specific processes in neuroscience.
But when applied to my own work in electronics,
it gains a whole new meaning.
It has the potential to create new concepts.
And it made me wonder: how exactly does the brain work?
Could we use it to build a new kind of computer?
Why is this so fascinating, you ask?
Because, everything considered, the brain uses 15 watts of energy.
That's 4 or 5 times less than a light bulb in your bathroom.
And yet, when you think about what your brain can do,
you have to admit that it's way better than a light bulb!
For example, if I were to ask you —
now this isn't a random example, it's a very difficult task for a PC today —
if I were to ask you the name of a president who looks like yoghurt.
Some of you know what I'm talking about. The kind of task that requires making connections,
between very different ideas, is extremely difficult for a computer.
It could do it if we needed it to, but it wouldn't use 15 watts, it would use a billion.
And I'm only exaggerating a little.
Could we use the brain as a guide to build a new, more efficient
breed of computer?
After all, it grows, it works, it has a network of neurons...
Basically, it's not that complicated.
The brain is full of neurons, a mass of tiny dots, all intertwined.
They're always talking, in constant communication. Complicated.
But when you take a closer look at the brain,
at what happens when the brain processes information,
when the sprinter relays his baton from one point to another,
sometimes he goes by little squares
and other times by little circles.
The squares are bits of memory,
the circles are bits of calculations.
Instead of going back and forth between them, he follows a straight path.
Instead of going back and forth all the time, the sprinter just keeps running in a straight line.
And this is much easier, much less exhausting.
Bottom line: he uses much less energy.
Great!
So what can we do with this?
Do you recognize this person?
I see some of you do!
She's very famous.
She posed for Playboy magazine in the 1970s.
She was in the centerfold, if you know what I mean.
Her name is Lena.
But she's also famous for another reason.
She was the first person to be scanned.
Her picture in the Playboy centerfold was scanned
by American researchers in computer science,
in electronics, in the 1970s.
Since then, this picture has become the standard for image processing,
for testing image processing algorithms.
It's quite funny.
10 years ago, she received a special prize from the IEEE,
an academic society that oversees everything electronic,
for her immense contribution to the field.
Seriously! She's everywhere, even today.
The image is a bit blurry,
but it has decent pixelation.
There are plenty of algorithms for processing this image and make it less fuzzy,
to make it sharper, more attractive.
We run these algorithms every day
on our PCs, our cell phones.
For example, for those of you who use Instagram, when you apply a sepia filter
you're using one of these algorithms.
This type of processing is being made possible by new structures inspired by the brain.
And it will result in huge energy savings.
Instead of using — I don't know — 15 watts, we won't need more than 0.5 watts.
We've cut it down by a factor of 30. That's huge!
So what does this mean?
It means we'll be able to make more powerful computers,
longer lasting cell phones
with longer lasting batteries. Lots of things.
But that isn't the main idea.
We can make a super computer. That's great,
but it's not the main point of my presentation.
The important thing — what I want you to understand —
is that we've brought together Romeo and Juliet.
This was, as you recall, our initial problem.
These two worlds — the electronic and the biological world — are finally communicating.
And the result is something completely unexpected.
My main message today to the students
here at INSA, and to everyone in this room, is:
Go see what's happening next door.
If you're in electronics,
go see what's happening in the biology department.
If you're in business,
go see what's happening in art, for example.
Break down the barriers.
History is full of examples of people breaking down barriers.
This was in 1989.
A lot of good came out of it.
My message today is:
Break down the barriers, open your eyes to what's happening around you,
and beautiful things will come of it.
Thank you.
(Applause)