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  • YAEL HANEIN: So I want to describe to you

  • research activity that is taking place

  • in my lab over the past several years,

  • including some extensive collaboration that we

  • do with several colleagues.

  • And I want to get started with describing

  • just a little bit the visual system.

  • The visual system basically looking

  • across different creatures, different animals,

  • is fundamentally the same.

  • And at the very core, it's the capacity

  • of the brain to reach out and to look into the environment.

  • And one of the fascinating things about the visual system

  • is that it's really adapted to accommodate

  • the different needs of different creatures.

  • So humans in particular have very strong needs, one of which

  • is actually to recognize facial expression.

  • And clearly, as humans we have developed technology

  • that goes hand in hand with our visual capacity.

  • So overall, put together, about 80% of what we perceive

  • and comprehend, but also remember and plan,

  • is based on visual information.

  • So we're really technological creatures, I mean,

  • and this is probably one of the best places

  • to highlight this point.

  • But it's really not just about survival.

  • It's survival, but also expanding our capacity

  • in terms of our ability to read, to learn, to plan

  • the future, which really goes hand in hand

  • with our technological capacity and our visual capacity.

  • Now the important thing to realize

  • is that technology and modern science

  • actually have some additional link with visual information.

  • And this is a little bit tricky to comprehend.

  • So if we look overall at longevity,

  • we all know that people live longer.

  • The numbers are quite amazing when we look at them.

  • And so if you just look at what was the reality just about

  • 100 years ago, people didn't live very long.

  • So modern medicine had immense capacity

  • at prolonging life and making all of us live much longer.

  • So clearly there are some differences

  • between developing and developed countries.

  • But generally in the developed world, people live very long.

  • And this has to do with the ability

  • to eradicate a lot of diseases that

  • typically cause early death.

  • Now how does that relate to vision?

  • So one of the consequences of living longer

  • is the fact that certain diseases, as I mentioned,

  • have disappeared.

  • But on the other hand, several other diseases

  • that were unknown before are becoming very prevalent.

  • And one of them is AMD, or age-related macular

  • degeneration, which is the situation where

  • the central part of our macula, or central part

  • of our visual system, which is the macula, it's

  • the center of the retina, becomes degenerate.

  • And that means that when we age, there's

  • an onset of the disease.

  • And when we look at the population

  • of 80-year-olds and above, there's

  • a staggering number of people that

  • will suffer from this disease.

  • So if you go ahead and extrapolate

  • what would be the situation in 20 years, in 50 years,

  • the numbers are going to be very high.

  • So the current estimates is by the year 2050,

  • among the American population, there

  • would be over 5 million people suffering from AMD.

  • Now AMD doesn't mean total blindness,

  • but what AMD means is that our capacity

  • to read, to write, to recognize faces

  • is severely damaged to the point that in many patients

  • it's damaged completely.

  • And the consequences are loss of independence, depression,

  • and a major financial burden on the patients themselves,

  • but also on additional circles of family and friends.

  • So by this point you're all spooked.

  • And this is probably the time to start

  • talking about the future and the technological solutions.

  • And so this is where we introduced

  • the issue of artificial vision.

  • Now artificial vision sounds like complete science fiction.

  • But in fact, over the last several decades,

  • there is a whole range of related technologies

  • that have been developed and have

  • been proven to do just what we're

  • aiming to do in artificial vision.

  • So cochlear implants are devices that

  • are implanted in the cochlea in the ear

  • and have been used already with just over 200,000 people.

  • And what these devices do, they can take auditory information,

  • transfer that into electrical stimulation,

  • and stimulate nerve cells, and basically

  • address the nerve track in order to stimulate information that

  • ultimately is conceived as auditory information.

  • And so this technology has been really the trigger

  • and the motivation to develop additional technologies

  • such as the artificial vision.

  • And so artificial vision are devices

  • that you see on the right-hand side.

  • These are actually devices, actual prototypes, two of which

  • have already passed even regulatory cycles

  • and are approved for use not for AMD patients,

  • but for RP patients.

  • And such devices utilize microfabrication technology

  • and allows people to see.

  • Now what does it mean, it allows people to see?

  • It allows them to have the sensation

  • of visual information.

  • So what these pioneering studies have demonstrated

  • is several very fundamental issues.

  • First, it has demonstrated the fact

  • that you can build a device.

  • You can implant it for a long term.

  • And you can transfer electrical signals

  • that are perceived by the brain as visual information.

  • The second point is that you can also

  • demonstrate using cochlear implants and these implants,

  • that the brain plasticity have the capacity to, over time,

  • to understand better and better this visual information that

  • is being transferred.

  • So basically the science fiction part of it

  • has been taking a little bit out of it in the sense

  • that we know that these things are technologically possible.

  • The challenge remains though that the systems that

  • have been developing over many, many, many years--

  • this is a long path it takes from the design

  • to the actual realization of these devices-- they're still

  • very bulky, very big, require external energy source,

  • and requires extensive wiring.

  • And often this wiring has to extend out

  • of the eyeball, which makes the whole thing pretty messy when

  • you think about it in terms of surgical procedures.

  • So that the moon shot thought is really to take all of that

  • and turn that into a compact device,

  • basically something that can be inserted neatly into the eye

  • and placed against the retina.

  • So this is clearly what you would

  • like to do when you talk about an artificial retina,

  • but then the question is how do you go about doing that?

  • So what you really need is new materials, either new polymers,

  • new nanotechnology tools, just tools that actually did not

  • exist when the original artificial retina devices were

  • beginning to be developed.

  • So now we do have new materials available.

  • And what we've been trying to do is really

  • to go back to the very basics and to try

  • to imitate the system to the very, very fundamental levels.

  • So a natural system is relied on photoreceptors.

  • The photoreceptors are the elements

  • that are degenerated in AMD.

  • And what you want is actually the capacity

  • to be able to elicit electrical information instead

  • of those elements, instead of these photoreceptors that

  • are gone.

  • Now in the natural system, especially in the macula,

  • there are a lot of these photoreceptors.

  • There's a very high density of them.

  • And they operate in a very efficient way.

  • And so what we're trying to do is

  • to use carbon nanotube as a scaffold

  • onto which we want to introduce energy harvesting

  • elements or photo harvesting elements,

  • and the combination of these two,

  • the photo conducting elements on the one hand

  • and the carbon nanotube as a scaffold on the other hand,

  • can simultaneously generate the needed electric field,

  • which is needed in order to stimulate the retina.

  • Now in terms of actually demonstrating that,

  • so one approach that we've demonstrated very recently

  • with colleagues from Bangalore is using conductive polymers.

  • So you can take newly-developed conducting polymers,

  • deposit them on the interface of electrodes.

  • You can take a blind retina, place the blind retina

  • on the interface, shine light in a very precise way,

  • and demonstrate that the retina can see.

  • So this is a blind retina that sees visual information that

  • are mediated by the special interfaces.

  • The actual approach, or the major effort in my lab,

  • is actually to use the carbon nanotubes as a scaffold.

  • And this is an ongoing work that we've

  • been doing for the past 10 years in which we've been constantly

  • demonstrating the great advantage of using carbon

  • nanotubes for this application.

  • So carbon nanotubes have several fundamental properties,

  • which are really ideal for this application.

  • One is that it's almost like a natural Velcro, which

  • makes a very strong and intimate contact

  • with biological systems.

  • And we've been demonstrating that in vitro, ex vivo,

  • and in vivo.

  • So these are absolutely fantastic materials

  • in binding to the biological system.

  • The other thing is that they are a fantastic electrochemical

  • system, and you can use them as electrodes

  • both for recording and stimulation.

  • You can really convince yourself that you

  • obtain absolutely fantastic recording capabilities just

  • because of their very large, three-dimensional structure.

  • The other thing, which comes from their entangled nature,

  • is the fact that you can make films from these surfaces.

  • You can work out the fabrication process in such a way

  • that you can integrate that into many different carriers,

  • into polymeric carriers, which are biocompatible, and can

  • automatically integrate this whole system

  • into a standalone device.

  • So when you take all of these together and use the carbon

  • nanotube as a scaffold, and now bring

  • into this party, the quantum rods,

  • now you have a system that can do both.

  • It can anchor or bind to the biological system,

  • but it can also do the energy transfer

  • of taking photons and converting them

  • into charge separation, which ultimately stimulate

  • the retina.

  • Now there's a lot of science in the science

  • fiction in the sense that you really

  • have to work out a lot of details.

  • There are many, many, many details,

  • and I have exactly 32 seconds to lay them out.

  • But you really have to work about how you couple the carbon

  • nanotubes and the quantum dots.

  • You really have to make sure that the system

  • is stable and biocompatible, that the charge transfer

  • happens in such a way that it doesn't damage the system.

  • And all of these things have to be, of course, proven.

  • But once you do that, you actually realize that it works.

  • And you can demonstrate again, using blind retina, ex vivo,

  • that using nice, sharply-defined optical pulses,

  • that you can stimulate the retina

  • and reconstruct visual information in essentially

  • a blind system.

  • So there's a long way to go in order

  • to fill the full picture of this.

  • But this is where we're at at the moment

  • and really looking forward for the future.

  • So just to conclude, the real challenge

  • is really at the bottom, not just to extend life,

  • but really to make sure that this prolonged life is

  • happy, healthy, and independent.

  • So thank you very much.

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