If you've had surgery, you might remember starting to count backwards from ten, nine, eight, and then waking up with the surgery already over before you even got to five.
And it might seem like you were asleep, but you weren't.
You were under anesthesia, which is much more complicated.
You were unconscious, but you also couldn't move, form memories, or, hopefully, feel pain.
Without being able to block all those processes at once, many surgeries would be way too traumatic to perform.
Ancient medical texts from Egypt, Asia and the Middle East all describe early anesthetics containing things like opium poppy, mandrake fruit, and alcohol.
Today, anesthesiologists often combine regional, inhalational and intravenous agents to get the right balance for a surgery.
Regional anesthesia blocks pain signals from a specific part of the body from getting to the brain.
Pain and other messages travel through the nervous system as electrical impulses.
Regional anesthetics work by setting up an electrical barricade.
They bind to the proteins in neurons' cell membranes that let charged particles in and out, and lock out positively charged particles.
One compound that does this is cocaine, whose painkilling effects were discovered by accident when an ophthalmology intern got some on his tongue.
It's still occasionally used as an anesthetic, but many of the more common regional anesthetics have a similar chemical structure and work the same way.
But for major surgeries where you need to be unconscious, you'll want something that acts on the entire nervous system, including the brain.
That's what inhalational anesthetics do.
In Western medicine, diethyl ether was the first common one.
It was best known as a recreational drug until doctors started to realize that people sometimes didn't notice injuries they received under the influence.
In the 1840s, they started sedating patients with ether during dental extractions and surgeries.
Nitrous oxide became popular in the decades that followed and is still used today.
although ether derivatives, like sevoflurane, are more common.
Inhalational anesthesia is usually supplemented with intravenous anesthesia, which was developed in the 1870s.
Common intravenous agents include sedatives, like propofol, which induce unconsciousness, and opioids, like fentanyl, which reduce pain.
These general anesthetics also seem to work by affecting electrical signals in the nervous system.
Normally, the brain's electrical signals are a chaotic chorus as different parts of the brain communicate with each other.
That connectivity keeps you awake and aware.
But as someone becomes anesthetized, those signals become calmer and more organized, suggesting that different parts of the brain aren't talking to each other anymore.
There's a lot we still don't know about exactly how this happens.
Several common anesthetics bind to the GABA-A receptor in the brain's neurons.
They hold the gateway open, letting negatively charged particles flow into the cell.
Negative charge builds up and acts like a log jam, keeping the neuron from transmitting electrical signals.
The nervous system has lots of these gated channels, controlling pathways for movement, memory, and consciousness.
Most anesthetics probably act on more than one, and they don't act on just the nervous system.
Many anesthetics also affect the heart, lungs, and other vital organs.
Just like early anesthetics, which included familiar poisons like hemlock and aconite, modern drugs can have serious side effects.
So an anesthesiologist has to mix just the right balance of drugs to create all the features of anesthesia, while carefully monitoring the patient's vital signs, and adjusting the drug mixture as needed.
Anesthesia is complicated, but figuring out how to use it allowed for the development of new and better surgical techniques.
Surgeons could learn how to routinely and safely perform C-sections, reopen blocked arteries, replace damaged livers and kidneys, and many other life-saving operations.
And each year, new anesthesia techniques are developed that will ensure more and more patients survive the trauma of surgery.
Greg Gage: Who wouldn't love acing a geography exam, remembering all the locations of the countries on a map or avoiding embarrassing situations of suddenly forgetting the person's name standing right in front of you.
It turns out that memory, like other muscles in the body, can be strengthened and enhanced.
But instead of practicing with flash cards, there may be an interesting way that we can hack our memory while we sleep.
(Music) Why do we sleep?
This has been a question asked since the early days of civilization.
And while we may not know the exact answer, there are a number of really good theories about why we need it.
Sleep is when the brain transfers short-term memories experienced throughout the day into long-term memories.
This process is called memory consolidation, and it's the memory consolidation theory that has scientists wondering if we can enhance certain memories over others.
There was a paper recently in the journal "Science" by Ken Paller and his colleagues at Northwestern that seemed to show that this may be true, and that piqued our curiosity.
Joud has been working on a DIY version of this task to see if we can improve memories through the use of sound in sleep.
So Joud, how do you test if we can improve our memories with sleep?
Joud Mar’i: We need a human subject.
[Step 1: Play a game] We have a memory game that we have on an iPad, and then we make our subject play this game and remember the images and where they appear on the screen.
GG: So this is like a memory game you used to play as a child, which picture was where.
And we tie each picture with a sound that represents it.
JM: So, if you can see a picture of a car, for example, and you would hear the car engine.
(Car engine starting) GG: Just before you go to sleep we're going to test you.
We're going to see how well you remember where the pictures are.
Every time you see the picture, you're going to hear the sound.
And now comes the experiment.
You're going to go take a nap.
[Step 2: Take a nap] And while you're sleeping, we're going to be recording your EEG.
JM: And then we wait for them to go into what's called the slow-wave sleep, which is the deepest phase of your sleep where it's really hard for you to wake up.
GG: OK, pause.
So, here's some information on sleep.
There are four stages: we have lighter stages of sleep and REM, but what we're interested in is called slow-wave sleep.
And it gets its name from the electrical signals called Delta waves that we record from the brain.
This is the part of sleep where scientists believe that memory consolidation can happen.
In this deep period of sleep, we're going to do something that you don't know we're going to do.
JM: Here's where the tricky part comes, and we start playing our cues.
(Car engine starting) GG: Do you play all the cues?
JM: No.
We only want to play half of them to see if there's a difference.
GG: So your hypothesis is the one that they were listening to while they're sleeping they're going to do better at.
JM: Yes, exactly.
GG: When you wake back up and play the game again, do you do better or worse than before a nap?
What we found is that if we played you a cue during your sleep, for example, a car -- You would remember the position of that car when you woke back up again.
But if we didn't play you the cue during the sleep, for example, a guitar, you'd be less likely to remember that guitar when you woke up.
The memories that were cued they remembered better than the ones they weren't, even though they don't remember hearing those sounds?
JM: Yes, we ask them.
GG: We know they're sleeping, they can't hear it, they wake up, they do better on those than the ones you didn't play.
GG: That's amazing.
JM: It's like magic.
GG: Joud ran this experiment on 12 people and the results were significant.
It's not that you remember things better; it's that you forget them less.
I was a huge skeptic when I first heard that you could do better at a memory test just by playing sounds during sleep.
But we replicated these experiments.
The facts and memories we collect throughout the day are very fragile, and they are easily lost and forgotten.
But by reactivating them during sleep, even without us being aware, it seems like we could make them more stable and less prone to forgetting.
That's pretty incredible.
Our brains are still active even when we're not.
So if you're like me and a bit forgetful, perhaps a solution is a pair of headphones and a soft couch.
I'm the product of a bold leadership decision.
After 1956, when Tunisia became independent, our first president, Habib Bourguiba, decided to invest 20 percent of the country's national budget in education.
Yes, 20 percent, on the high end of the spectrum even by today's standards.
Some people protested.
What about infrastructure?
What about electricity, roads and running water?
Are these not important?
I would argue that the most important infrastructure we have are minds, educated minds.
President Bourguiba helped establish free, high-quality education for every boy and every girl.
And together with millions of other Tunisians, I'm deeply indebted to that historic decision.
And that's what brought me here today, because today, we are facing a global learning crisis.
I call it learning crisis and not education crisis, because on top of the quarter of a billion children who are out of school today, even more, 330 million children, are in school but failing to learn.
And if we do nothing, if nothing changes, by 2030, just 13 years from now, half of the world's children and youth, half of 1.6 billion children and youth, will be either out of school or failing to learn.
So two years ago, I joined the Education Commission.
It's a commission brought together by former UK Prime Minister and UN Special Envoy for Global Education Gordon Brown.
Our first task was to find out: How big is the learning crisis?
What's actually the scope of the problem?
Today we know: half of the world's children by 2030 will be failing to learn.
And that's how actually we discovered that we need to change the world's focus from schooling to learning, from just counting how many bodies are in classrooms to actually how many are learning.
And the second big task was, can we do anything about this?
Can we do anything about this big, vast, silent, maybe most-neglected international crisis?
And what we found out is, we can.
It's actually amazing.
We can, for the first time, have every child in school and learning within just one generation.
And we don't even have to really invent the wheel to do so.
We just need to learn from the best in class, but not any best in class -- the best in your own class.
What we did is actually we looked at countries by income level: low-income, mid-income, high-income.
We looked at what the 25 percent fastest improvers in education do, and what we found out is that if every country moves at the same rate as the fastest improvers within their own income level, then within just one generation we can have every child in school and learning.
Let me give you an example.
Let's take Tunisia for example.
We're not telling Tunisia, "You should move as fast as Finland."
No disrespect, Finland.
We're telling Tunisia, "cgeorge@example.com."
They spend similar amounts for primary and secondary pupils as percentage of GDP per capita, but achieves today higher results.
Vietnam introduced a standardized assessment for literacy and numeracy, teachers in Vietnam are better monitored than in other developing countries, and students' achievements are made public.
And it shows in the results.
In the 2015 PISA -- Program for International Student Assessment -- Vietnam outperformed many wealthy economies, including the United States.
Now, if you're not an education expert, you may ask, "What's new and different?
Don't all countries track student progress and make those achievements public?"
No.
The sad answer is no.
We are very far from it.
Only half of the developing countries have systematic learning assessment at primary school, and even less so at lower secondary school.
So if we don't know if children are learning, how are teachers supposed to focus their attention on delivering results, and how are countries supposed to prioritize education spending actually to delivering results, if they don't know if children are learning?
That's why the first big transformation before investing is to make the education system deliver results.
Because pouring more money into broken systems may only fund more inefficiencies.
And what deeply worries me -- if children go to school and don't learn, it devalues education, and it devalues spending on education, so that governments and political parties can say, "Oh, we are spending so much money on education, but children are not learning.
They don't have the right skills.
Maybe we should spend less."
Now, improving current education systems to deliver results is important, but won't be enough.
What about countries where we won't have enough qualified teachers?
Take Somalia, for example.
If every student in Somalia became a teacher -- every person who finishes tertiary education became a teacher -- we won't have enough teachers.
And what about children in refugee camps, or in very remote rural areas?
Take Filipe, for example.
Filipe lives in one of the thousands of communities alongside the Amazonas rivers.
His village of 78 people has 20 families.
Filipe and a fellow student were the only two attending grade 11 in 2015.
Now, the Amazonas is a state in the northwest of Brazil.
It's four and a half times the size of Germany, and it's fully covered in jungle and rivers.
A decade ago, Filipe and his fellow student would have had just two alternatives: moving to Manaus, the capital, or stopping studying altogether, which most of them did.
In 2009, however, Brazil passed a new law that made secondary education a guarantee for every Brazilian and an obligation for every state to implement this by 2016.
But giving access to high-quality education, you know, in the Amazonas state, is huge and expensive.
How are you going to get, you know, math and science and history teachers all over those communities?
And even if you find them, many of them would not want to move there.
So faced with this impossible task, civil servants and state officials developed amazing creativity and entrepreneurship.
They developed the media center solution.
It works this way.
You have specialized, trained content teachers in Manaus delivering classroom via livestream to over a thousand classrooms in those scattered communities.
Those classrooms have five to 25 students, and they're supported by a more generalist tutoring teacher for their learning and development.
The 60 content teachers in Manaus work with over 2,200 tutoring teachers in those communities to customize lesson plans to the context and time.
Now, why is this division between content teacher and tutoring teacher important?
First of all, as I told you, because in many countries, we just don't have enough qualified teachers.
But secondly also because teachers do too many things they're either not trained for or not supposed to do.
Let's look at Chile, for example.
In Chile, for every doctor, you have four and a half people, four and a half staff supporting them, and Chile is on the low end of the spectrum here, because in developing countries, on average, every doctor has 10 people supporting them.
A teacher in Chile, however, has less than half a person, 0.3 persons, supporting them.
Imagine a hospital ward with 20, 40, 70 patients and you have a doctor doing it all by themselves: no nurses, no medical assistants, no one else.
You will say this is absurd and impossible, but this is what teachers are doing all over the world every day with classrooms of 20, 40, or 70 students.
So this division between content and tutoring teachers is amazing because it is changing the paradigm of the teacher, so that each does what they can do best and so that children are not just in school but in school and learning.
And some of these content teachers, they became celebrity teachers.
You know, some of them run for office, and they helped raise the status of the profession so that more students wanted to become teachers.
And what I love about this example is beyond changing the paradigm of the teacher.
It teaches us how we can harness technology for learning.
The live-streaming is bidirectional, so students like Filipe and others can present information back.
And we know technology is not always perfect.
You know, state officials expect between five to 15 percent of the classrooms every day to be off live-stream because of flood, broken antennas or internet not working.
And yet, Filipe is one of over 300,000 students that benefited from the media center solution and got access to postprimary education.
This is a living example how technology is not just an add-on but can be central to learning and can help us bring school to children if we cannot bring children to school.
Now, I hear you.
You're going to say, "How are we going to implement this all over the world?"
I've been in government myself and have seen how difficult it is even to implement the best ideas.
So as a commission, we started two initiatives to make the "Learning Generation" a reality.
The first one is called the Pioneer Country Initiative.
Over 20 countries from Africa and Asia have committed to make education their priority and to transform their education systems to deliver results.
We've trained country leaders in a methodology called the delivery approach.
What this does is basically two things.
In the planning phase, we take everyone into a room -- teachers, teacher unions, parent associations, government officials, NGOs, everyone -- so that the reform and the solution we come up with are shared by everyone and supported by everyone.
And in the second phase, it does something special.
It's kind of a ruthless focus on follow-up.
So week by week you check, has that been done, what was supposed to be done, and even sometimes sending a person physically to the district or school to check that versus just hoping that it happened.
It may sound for many common sense, but it's not common practice, and that's why actually many reforms fail.
It has been piloted in Tanzania, and there the pass rate for students in secondary education was increased by 50 percent in just over two years.
Now, the next initiative to make the Learning Generation a reality is financing.
Who's going to pay for this?
So we believe and argue that domestic financing has to be the backbone of education investment.
Do you remember when I told you about Vietnam earlier outperforming the United States in PISA?
That's due to a better education system, but also to Vietnam increasing their investment from seven to 20 percent of their national budget in two decades.
But what happens if countries want to borrow money for education?
If you wanted to borrow money to build a bridge or a road, it's quite easy and straightforward, but not for education.
It's easier to make a shiny picture of a bridge and show it to everyone than one of an educated mind.
That's kind of a longer term commitment.
So we came up with a solution to help countries escape the middle income trap, countries that are not poor enough or not poor, thankfully, anymore, that cannot profit from grants or interest-free loans, and they're not rich enough to be able to have attractive interests on their loans.
So we're pooling donor money in a finance facility for education, which will provide more finance for education.
We will subsidize, or even eliminate completely, interest payments on the loans so that countries that commit to reforms can borrow money, reform their education system, and pay this money over time while benefiting from a better-educated population.
This solution has been recognized in the last G20 meeting in Germany, and so finally today education is on the international agenda.
But let me bring this back to the personal level, because this is where the impact lands.
Without that decision to invest a young country's budget, 20 percent of a young country's budget in education, I would have never been able to go to school, let alone in 2014 becoming a minister in the government that successfully ended the transition phase.
Tunisia's Nobel Peace Prize in 2015 as the only democracy that emerged from the Arab Spring is a legacy to that bold leadership decision.
Education is the civil rights struggle, it's the human rights struggle of our generation.
Quality education for all: that's the freedom fight that we've got to win.
Thank you.
(Applause)