Dr. E.J. Chichilnisky: How the Brain Works, Curing Blindness & How to Navigate a Career Path

welcome to the huberman Lab podcast where we discuss science and science-based tools for everyday [Music] life I'm Andrew huberman and I'm a professor of neurobiology and Opthalmology at Stanford School of Medicine my guest today is Dr EJ chelski Dr EJ chelski is a professor of neurosurgery Opthalmology and Neuroscience at Stanford University he is one of the world's leading researchers trying to understand how we see the world around us that is how visual perception occurs and then applying that information directly to the design of neural prosthesis literally robotic eyes that can allow blind people to see

once again today's discussion is a very important one for anyone who wants to understand how their brain works indeed EJ spells out in very clear terms exactly how the world around us is encoded by the neurons the nerve cells within our brain in order to create these elaborate visual images that we essentially see within our minds and with that understanding he explains how that can be applied to engineer specific robotic Ai and machine learning devices that can allow human brains not only to see once again in the blind but also to perceive things that typical

human brains can't and indeed for memory to be enhanced and for cognition to be enhanced this is the direction that Neuroscience is going and in the course of today's discussion we have the opportunity to learn from the world World expert in these topics where the science is now and where it is headed during today's discussion we also get heavily into the topic of how to select one's professional and personal path and indeed you'll learn from Dr chelski that he has a somewhat unusual path both into science and through science so for those of you that

believe that everyone that's highly accomplished in their career always knew exactly what they wanted to do at every stage you will soon learn that that is absolutely not the case with EJ he described tries wandering through three different graduate programs taking several years off from school in order to dance Yes you heard that correctly to dance and how that wandering and indeed dancing helped him decide exactly what he wanted to do with his professional life and exactly what specific problems to try and Tackle in the realm of Neuroscience and medicine it's a discussion that I'm

certain that everybody scientist or no young or old can benefit from and can apply the specific tools that EJ describes in their own life and Pursuits before we begin I'd like to emphasize that this podcast is separate from my teaching and research roles at Stanford it is however part of my desire and effort to bring zero cost to Consumer information about science and science related tools to the general public in keeping with that theme I'd like to thank the sponsors of today's podcast our first sponsor is eight sleep eight sleep makes Smart mattress covers with

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enter the code huberman to save 20% off your first order again that's r.com and enter the code huberman at checkout today's episode is also brought To Us by betterhelp betterhelp offers Professional Therapy with a licensed therapist carried out online now I've been going to therapy for well over 30 years initially I didn't have a choice it was a condition of being allowed to stay in school but pretty soon I realized that therapy is extremely valuable in fact I consider doing regular therapy just as important as getting regular exercise including cardiovascular exercise and resistance training which

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an astronaut you go places no one else has been willing to go before he developed new technologies in order to do that all with the Bold mission of trying to understand how the nervous system which of course includes the brain works and how to make it better with engineering so today we are going to get into all of that but just to start off and get everybody on the same page maybe we could just take a moment and talk about the brain and nervous system and you know what it consists of that allows to do

all the sorts of things that we're going to get into like see things in our environment and respond to those things in our environment so at risk of throwing too much at you right out the gate what's your one to five minute version of how the brain works oh I don't have a one to five minute version of how the brain works but I can tell you how I think uh vision is initiated in the brain and um you and I go back a long way so we have a lot of common understanding about this

but I'll narrate it from scratch if if that makes sense um so vision is initiated in the retina uh of the eye which is a sheet neural tissue at the rear of the eye that captures the light that is incident on the eye that comes in through the through the eye transforms that light into electrical signals processes those electrical signals in interesting ways and changes them up and then sends that visual information to the brain where it is used to bring about our sense of vision and uh you you asked me about the 1 to

five minute version how the brain works I don't know but I do know that the brain receives all these patterns of electrical activity coming out of these nerve cells and the retina and somehow assembles that into our visual experience whether that be responding to things coming at us or our circadian rhythm that that govern our sleep and behavior or identifying objects for prey or avoiding Predators or appreciating Beauty and what we know is that the brain receives a fantastically complex set of signals from the retina and puts that all together into our visual experience and

we are very visual creatures obviously so I think that's a big part of how the brain works because so much of what we do revolves around vision revolves around how the brain puts together these signals coming out of the retina and I would love to understand how that works at the moment I don't uh and what we're trying to do is get a really complete understanding of how that begins in the retina and then how we can restore it in those who have lost sight why focus on this issue in the retina this thin set

of layers of neurons that line the back of the eye what why why explore there I mean obviously there are centers within the brain that of course contain neurons nerve cells that are involved in Vision if one wants to understand visual perception and I agree by the way that visual perception is one of the most dominant forces in the quality and experience of our life why focus on the retina why not focus on the visual cortex or the visual Thalamus I me what's so special about the retina well we have to focus on all of

it because understanding the retina won't give us a full understanding of how all this works obviously and if you don't have your visual cortex and visual Thalamus you won't see but if you don't have your retina you also won't see you won't even have a chance to see so I focus on the retina because um I enjoy the possibility that we can really understand a piece of the nervous system in my lifetime in our lifetimes we can understand it so well that we can build it replace it restore its function that's farther off in this

in the central regions of the brain it's going to be quite a bit harder um I find satisfaction in really understanding something so well that I can write down in a mathematical formula what it's doing that I can test my hypotheses up and down and yes we really get how this little machine works and that I can engineer devices to replace the function of that circuit when it's lost that to me is just deeply satisfying but there also has is a really fundamental role for people who want to go and do more exploratory work in

the visual brain as you mentioned in the visual cortex and the phalus and other places because ultimately those retinal signals won't lead to anything if those areas aren't putting it all together to govern our perception and our ultimately our Behavior so let's talk about the retina in its full Beauty and detail three layers of cells line the back of the eye like a pie crust somehow take light that comes into the eye lens focuses that light if it doesn't do that well we put lenses in front of our eyes such as contact lenses or spectacles

and somehow takes that light and transforms it as you said into neural signals and processes that within the retina so let's take a deep dive into the retina and do so with the understanding at least my understanding is that in part thanks to your work and the work of others this is perhaps the best understood piece of the brain yes I think it's a solid argument that it's the best understood piece of the brain and uh we'll turn back to that in a minute so um the retina begins with a sheet of cells called the

photo receptor cells that are highly specialized these are cells that essentially don't exist anywhere else in the brain and what they do is transform light energy into electrical signals in neurons very specialized very uh demanding cells they require a lot of Maintenance and they die relatively easily which is what gives rise to some some of the forms of blindness those are the you might call them pixel detectors they're tiny cells called photo receptors that each one captures light from a particular location in the world that sheet of cells has done that initial transduction process where

light is converted into neural signals that the brain can then begin to work with the second layer is responsible for processing adjusting changing mixing and matching uh comparing signals and different neurons many complex operations that we're still trying to understand and consists of dozens of distinct cell types that extract features if you will of the visual World from the elementary pixels represented in the photo receptor cells so that second layer is receiving the input from that sheet of photo receptors and picking stuff out of it the third layer of cells is the so-called retinol gangan

cells that's the only uh term that I'd like to probably will come up repeatedly in this conversation uh so for your for your viewers and listeners um these retinol ganglin cells are the ones who are responsible for taking the signals that are there in the retina and sending them to the brain so that the process of vision can begin they are the The Messengers if you will from the retina to the brain the retinal ganglin cells and there are about 20 different types in humans um are again feature extractors they pick out different bits and

pieces of the visual scene and send interesting stuff to the brain trying to leave out the uninteresting stuff and the 20 or so cell types all pick out different types of information from the visual scene you can sort of think of them as Photoshop filters each cell type in the retina um again about 20 different Gangland cell types each type represents the full scene the entire visual world but picks out different features such as some cells pick out spatial detail tiny little Points of Light almost some cells pick out and Signal information about things that

are moving in the visual World some cells pick out information that's been captured about different wavelengths from the photo receptor cells and there thereby giving us our sensations of color and probably more things in those 20 different gangin cell types that we don't fully understand the result then is that the retina has this sort of a representation of the visual world but it has 20 different representations not one it's not one picture that comes out of the retina and gets sent to the brain no no no it's 20 different pictures and you can think of

maybe as 20 different photoshopped pictures but one of them has the edges highlighted one of them has the colors highlighted one of them has movement uh encoded in it and these somehow these filters send the information to many different targets in the brain and our brain puts it Al together and then we have a cohesive sense of the visual World which is the remarkable feature that we really don't understand amazing is it fair for those that don't work with Photoshop to think about these um different Photoshop filters perhaps as like different movies of the visual

world one movie contains the outlines of objects and people and things another movie is showing the motion of blobs in the environment meaning whatever is moving environment is kind of just represented as blobs another movie is just the color in the environment another and then all of those what I'm calling movies are sent into the brain and then the brain somehow combines those in ways that allow us to see each other and see cars and objects and recognize faces is that is that one way to think about that that's exactly how I think about it

maybe it's a better way to say it no I I I like the Photoshop filter uh analogy I just for those that don't work with Photoshop um you know I I just think that the movie analogy might might be a decent alternative how the retina works is an example we think of how all sensory systems work there's an initial representation in a specialized cell type that is it is that is responsible for and capable of extracting physical features from the world and then neural circuits in the brain use that information in different ways to grab

stuff out of the visual world in the auditory system there's the the sound world is represented also in specialized cells that capture sound energy and transduce that into neural signals and then subsequent p uh stages of processing in the auditory system pick out different features of our auditory world like the frequency how high or how low a tone is right the direction it's coming from right the movement of it uh how loud it is different features are extracted so the we think the visual system is just an example of how the external world is represented

in our brain and of course in some sense a a philosophical approach to the brain is really saying well there's the sensory world and then there's the actions we take and there's almost nothing else that we really know other than those two things how the sensory world comes in and then finally it results in our action that's what our brain is about because vision is so important for people I find it absolutely compelling and fascinating I mean as an example as you know well many people study rodents uh to understand how different aspects of the

brain work and um you know rodents are interesting animals and do all sorts of really cool things but they interact with the world differently than we do they in in a lot of ways they sense by smelling they they identify objects by smelling and they navigate with their whiskers in to a large extent we don't do any of that you don't navigate with your whiskers at least I don't think you do you don't recognize me when I walk in the room by my smell no you use for all that and we humans use Vision so

it's a really fundamental aspect of who we are as biological creatures I wonder if just for sake of entertainment uh we could think about how the human retina and therefore Vision in our species differs a little bit from some extreme examples of vision in other species not to make this a comparative um or Zoological um exploration but just to really illustrate the fact that the specific cell types within our retinas create a visual representation of the outside world that can be and often is very different from that of other species um for instance or at

least my understanding is that the mantis shrimp sees I don't know 60 to 100 different variations of each color that we are essentially blind to because their photoreceptors can detect very subtle differences in red for instance long wavelengths of light what most people refer to as red um pit vipers cons sense heat emissions essentially with their eyes but also other organs um and on and on you know it I raise this because I think the the human neuro retina is such an incredible example of extracting features from the visual world that then we recreate but

I think it's also worth reminding everyone and ourselves that it's not a complete representation of what's out there like there's a lot in light that we don't see because our neuro retina just can't turn it into electrical signals right you want to give some examples of what we can't see and if any um particular examples from the Animal Kingdom Delight you feel free to throw those out well one thing you mentioned color um we experience a rich sensation of color when we look at the world and say wow I see all these colors that's immediate

and that's just how we talk about it but in fact we have very little information about color color is a very high-dimensional complex thing or wavelength I should say wavelength information really is about how much energy there is in the light around us at different wavelengths we only have three sort of snapshots of that in our retinas with the three different types of photo receptor cells that are sensitive to different wavelength different bands of the wavelength Spectrum three is not a lot as you just said other creatures have many more ways of capturing wavelength information

and one way you can verify for yourself that we just have three is to realize that if you look at your TV there are only three primaries on your TV there's a red there's a green and there's a blue that's it and from those three primaries the entire richness of the experience on your TV set is uh composed so with just those three things you basically are able to create any human visual sensation well the mantis shrimp would be like that's nothing there's so much more stuff out there that's not represented on this TV if

you could speak to the mantis shrimp another thing we we maybe don't see another example of a difference in the animal kingdom is so um again taking rodents as an example one of the one of the things rodents have to do is to not be hunted by birds that are coming down toward them and so it it appears that there are cells in the retina that are seem to be quite sensitive to what to uh looming to something dark that's getting bigger uh like a shadow coming from a bird coming down at you we don't

know for sure that this is exactly what causes animals to avoid being eaten by birds but there's there's interesting evidence in that direction that's not really a big thing for us for humans as far as I know we're not typically hunted by huge birds so that's not a thing we need and I think that's that's where comes back to where you were headed if I understand right um which is we occupy different biological niches we and the Manta shrimp and the rodents and our visual systems reflect that we have different stuff that we're looking for

in our visual environment than other creatures are and so our eyes are different and that's one of the reasons that we emphasize work on the human retina um as opposed to other certain other animal species that would be less clearly relevant to the visual experience you and I have so let's talk about these incredible experiments that your laboratory has been doing for several decades now I've had the uh privilege of sitting in on some of these experiments and they are very involved um to say the least if you could just walk us through one of

these experiments I think the audience would appreciate understanding what goes into quote unquote trying to understand what's going on in the electrical activity of these specific retinal cell types the retinal gangling cells in particular um you know what does this look like you know you're in your laboratory at Stanford and you get a phone call someone says I got a retina what happens next we scramble like crazy we drop everything we're doing cancel all our appointments and get ourselves ready for 48 hours of non-stop work down in the lab getting as much data as we

possibly can from the retina the most exciting example of what you just said is when we get a human retina when for example there's a a donor who has died and the retina is available for research we jump at that opportunity how soon after uh the person is deceased do you need to get the eye Globe the eyeball in order to get the retina in a condition that would allow you to record electrical signals from it a few minutes just you're waiting in the hospital um typic the way we typically get these eyes is from

brain dead individuals so people who are legally and medically dead but they're hearts are still pumping and therefore their retinas are still alive and functioning when when those individuals uh are used their the bodies of those individuals are used for organ donations we can benefit from that organ donation setup that organ distribution centers do to save many people's lives and also to promote research so we sometimes get those retinas and that begins the experiment for us um I'm gonna ask for a few more details here just to put the picture in people's minds and not

to be gruesome I just really want people to understand what's involved here so you'll get a call we've got a a patient who is soon to be deceased um they've consented to giving their eye Globes their eyeballs for research so that you can study the human retina y um is it you who goes over and takes the eyes out does somebody do that or hand them to you in a bucket of ice I'm sorry if I'm making people queasy at all but this is folks how uh one goes about trying to understand how the human

brain works absolutely and this is also how you go about donating your heart so that you can save somebody else's life who needs a heart transplant the same incredible organizations that do the harvesting of the tissue for us their primary goal is to do that for organ donations to save lives they save lives every day these people are incredible donor Network West is one of those organizations the one that we work with um they're really amazing um so their technicians or a retinal surgeon will take the eye out give it to myself or some somebody

from my lab who will bring it back to the lab and we have a way to keep the eye alive and functioning just the eye by itself is this always at Stanford or do you sometimes travel elsewhere local hospitals up to an hour away so then you drive them back we drive them back it's the retina Express and when when we're bringing back the retin Express it's uh again it's all hands on deck in our lab we are scrambling setting up all of our equipment getting everything ready you've been at these experiments they're intense and

they really are really are 48 hour marathons of incredible activity by really dedicated individuals so um we we might get those eyes sometimes get them at 2 in the morning that's common and from that to in the morning time um Begins the experiment so we bring the eyes back we open them up and we we have access to the rear of the eye which is what the where the retina is it's a thin sheet of neural tissue at the back part of the eye we hemis the eye cut it in half so that we can

see the back it's like half of a glow if you will and then we put in relaxing cuts and lay it out flat so we can see what we're working with and we take little segments of retina out in the subsequent 48 Hours cut them out maybe a 3X3 millimeter piece of the retina a little chunk of retinal tissue and bring it into an electrophysiology recording and stimulation apparatus that allow allows us to interact with it and we do two types of experiments with that so this electrophysiological recording and stimulation apparatus is very custom built

by our physics collaborator who have developed high-end equipment it allows us to record and stimulate through 512 channels simultaneously at very high density this is pretty high-end stuff in terms of uh technology for interrogating and manipulating the electrical signals in the retina that's what we specialize in in my lab could I just ask a question about this device um I've seen it before uh it's very small as you mentioned your recording from a few millimet square of the of the retina um from this recently deceased patient um it looks a little bit like a bed

of nails right like tiny little microwires all arranged very Clos to one another you got the retina laying down on top of it and that bed of nails can extract meaning record the electrical signals that are coming out of the retinal gangion cells that's right and the retina is still alive so you are in a position to shine light on it and essentially um make it behave um um in the same way it would if it were still lining the back of a healthy alive person that is the beauty of these experiments so because we

can keep the retina alive and happy and because the retinal ganglin cells the cells that are the ones that message the visual information to the brain are on the surface we can put them right next to the electrodes and we can record their electrical activity in other words we record the signal that those cells would have sent to the brain if they were still in the living person and at the same time as you said we can focus an image that we create on a computer display onto the retina so we're treating the retina if

you will as a little electronic circuit which it almost is honestly delivering light to the photo receptor cells so that they are electrically excited and then recording the electrical activity that the retina is sending out if you will that allows us to study how the retina Works normally what we also do with that same electrical apparatus is turn around and pass current through those electrodes in order to see if we can activate those ganglin cells directly with no light just electrodes why do we do that we do that because it allows us to design future

methods of restoring Vision by electrical stimulation of the retina which we'll probably talk about in a few minutes I'd like to take a brief moment and thank one of our sponsors and that's ag1 ag1 is a vitamin mineral probiotic drink that also contains adaptogens I started taking ag1 way back in 2012 the reason I started taking it and the reason I still take it every day is that it ensures that I meet all of my quotas for vitamins and minerals and it ensures that I get enough Prebiotic and probiotic to support gut health now gut

health is something that over the last 10 years we realized is not just important for the health of our gut but also for our immune system and for the production of neurotransmitters and neuromodulators things like dopamine and serotonin in other words gut health is critical for proper brain functioning now of course I strive to consume healthy Whole Foods for the majority of my nutritional intake every single day but there are a number of things in ag1 including specific micronutrients that are hard to get from Whole Foods or at least in sufficient quantities so ag1 allows

me to get the vitamins and minerals that I need probiotics prebiotics the adaptogens and critical micronutrients so anytime somebody asks me if they were to take Just One supplement what that supplement should be I tell them ag1 because ag1 support so many different systems within the body that are involved in mental health physical health and performance to try ag1 go to drink a1.com huberman and you'll get a year supply of vitamin D3 K2 and five free travel packs of ag1 again that's drink a1.com huberman let's take this moment to talk a little bit about cell

types so um you mentioned there are about 20 different types of these retinal gangling cells what we may refer to in brief as r gc's so retinal gangling cells rgc's same thing and as you mentioned these cover the entire retina so that if each cell type is extracting a different set of features from the visual World motion color specific colors Etc that essentially no location in the world around us fails to be represented by these cells put differently these cells are looking everywhere um each cell cell type is looking everywhere um so that if movement

occurs in any region of our visual world we are in a position to detect it um but maybe we could talk a little bit about cell types cell types is such an important theme in the field of Neuroscience and indeed in all of biology but it's actually not something we have talked about very much on this podcast before either in Solo episodes or in guest episodes um I don't have any specific reason for that we've talked about brain areas prefrontal cortex basil ganglia anterior mingal cortex and on and on we' talked about neural circuits but

we've never really talked about cell types so the gangan cells as other you let me down no talking about cell types well but that's why you're here that's why I'm here that's why you're here um tell us about cell types how do you figure out if you have a cell type how do you know if it's a cell type or you know is it the shape is it how it responds um how do you know if you have a cell typee what what's this about and I want to just um put in the back of

this question um or rather in the back of people's minds that um this issue of cell types is not just an issue pertinent to the retina this is an issue that is critical to understanding how the brain works absolutely it's critical to understand Consciousness I know a lot of people like what is consciousness right we're not going there just yet but uh what are cell types how do you determine if you have a cell type and why is this so important to understanding how the brain works yeah I mean as as you said as as

far as we understand every single brain circuit is full of very distinct cell types those cell types are distinguished by their genetic expression their shapes and sizes which other cells they do contact and which cells they don't contact where they send their information to in other parts of the brain and what they represent and as far as we know this is true throughout the brain and it's true in the retina the different gangling cell types retinal ganglin cell types about 20 of them Each of which is looking at the whole visual scene extracts different stuff

this cell type one extracts one thing cell type two extracts something else but they all represent the entire visual scene but those cell types we know from lots of beautiful work work that you're closely connected to and some of which you've done um those cell types have different morphology different shapes and sizes different patterns of gene expression different targets in the brain they send their outputs to different places in the brain so really to study the retina without understanding cell types you're kind of lost right away you have to know what's going on with the

cell types otherwise you can't make sense of this retinol signal the way we we identify them in two ways and they're different for different purposes the the basic way we identify the different cell types is their function because we study their function we study how they respond to light images and we can clearly separate them out and in fact it's it's a simple thing to say but it's really true our 512 electrod technology which you've seen in our lab and stuff that developed with collaborators um about 20 years ago um was crucial for this because

with that 512 electrode technology we could see many cells of each type and we could clearly parse them apart from one another whereas previous studies working on one cell at a time had great difficulty doing that so with our technology with 512 electrodes we record hundreds of cells simultaneously we say oh there's 20 of these there are 50 of those there's 26 of those and here they are and we can just set them in different bins and say okay this is what's present in this retina just what the information is they're extracting there's another purpose

again referring forward to the neuroengineering aspect we need to identify the cell types not just based on what visual information they carry but based on their electrical features properties electrical properties of the cells cells as you know neurons are electrical cells they fundamentally receive and transmit electrical information and the way that they do that has a distinctive electrical signature that turns out to be super important for developing devices to to restore Vision could you explain how you determine what a given cell type does its electrical properties um let's just draw a mental image for people

uh the retina's taken out of this deceased individual put down on this bed of nails of electrodes those electrodes can detect electrical signals within the gangling cells you are able to shine light onto the retina and see how the retinal gangling cells respond meaning what electrical signals they would transmit to the brain if they were still connected to a brain they're not connected to a brain in the experiment they're sitting there they're trying but they're trying I could imagine playing those cells a movie of I don't know a checkerboard going where every um Square on

the checkerboard goes from white to black to gray could do that I could um play a cartoon I could um show it uh this year's Academy Award winner for best picture like how do you decide what to show the retina this is a human being's retina after all uh presumably it looked at things that are relevant to human beings until that person died but how do you determine cell type electrical signals if you don't know what specific things to show it I mean you're going to show it I don't know Disney movies like what what

do you show it so what we shown now reflects the fact that we've built up a lot of information and our work stands on the shoulders of many scientists who have studied the retina for decades to figure out what different cell types respond to and um we know that certain cell types respond primarily to increments of light when light gets brighter than it was so it change from a certain brightness to a higher brightness this particular cell type fires another cell type fires or send spikes to the brain when it gets darker some cell types

uh respond primarily to large Targets in the visual World other cell types respond better to small Targets in the visual World some cell types respond to different wavelengths of light that we can identify there exists certain cell types that are still poorly understood that respond to movement so we can tailor visual stimuli to types that we kind of already know about because of much preceding research that's not actually how we do it in our experiments for the most part instead we use a very unbiased flickering checkerboard pattern as it turns out which is a really

efficient unbiased way to sample many cells simultaneously so that in a half hour of electrical recording from a retina we can figure out what all the 512 or so cells are that we're recording and know all of their types and the way we do that is to play essentially random garbage TV snow Type image to the retina for a period of time and determine which bits of of brightening or darkening or movement or whatever in that random garbage activated this particular cell by looking AC at average across the half hour recording and saying oh it

looks like this cell was always firing when it became bright in this region of the screen that must be an on Cell sensitive to light in this region of the screen and so on so we have sophisticated efficient ways of doing it but it all comes back to these basic things about what features in the visual World tend to cause a given cell to send a signal to the bra yeah that makes a lot of sense so you take essentially what you called random garbage um snow white black and gray pixels on a screen yep

the retina views that and then the cells in the retina will respond every once in a while with an electrical potential they'll fire as we say spike it's sometimes called and then you take sort of a forensic approach a bit later you look back in time and you say you know what was the arrangement of pixels in this random garbage right before this cell fired an electrical potential that's right a spike and then from that you can reconstruct the preferred stimulus yeah right the you can say oh this cell and cells around it seem to

like motion of things going in a particular direction for instance and um how do you know know that the cell doesn't also like a bunch of other stuff that you didn't pick up on using this random garbage yeah two things for let let me just say for the record we don't record from these cells that signal Motion in particular directions they are an elusive cell type that is best understood in rodents and other creatures and not well understood in the primate as you know although some people are discovering potential cells of that type now and

have have recently discovered them okay so let's say cells that respond to like spots that are red um you know that go from dim red to bright red right yeah so we can go through that colored TV snow and pick out the cells that responded to a transition of the kind you described from darker to lighter or from Greener to redder or something like that cells tend to respond to Transitions in the visual scene rather than static imagery um and so we can pick that stuff out but you asked the question well G is the

TV snow gon to capture everything about what these cells are doing that's a really important question that I want to just mention more um quite likely not that's a scientific instrument it's an unbiased way to sample a whole bunch of cells you know first cut look at you know generally speaking what are they up to but that doesn't mean we've really captured their role in natural visual perception because actually you don't go through the World perceiving visual snow you go through the world perceiving objects and meals and mates and targets and all these things right

so the study of how the retina responds to more naturalistic visual stimuli uh in my lab and in many other labs around the world is really get getting off the ground now and I would say we have limited understanding um I would say we know that our simple laboratory experiments with the TV snow don't capture the whole story there's more there're about 20 different cell types in the retina we have basic characterizations of seven of them if you count a certain way um we know that there are another 15 or so lurking right behind the

curtain that we've started to sample we don't know what naturalistic targets they respond to in the visual life of the animal that's work that's underway exciting interesting work because this we know that the r they got to be there for something one one way to think of it I'm I'm pretty sure you think think of it this way too is that the retina is a highly evolved organ with a lot of evolutionary pressure for it to be efficient to have a small optic nerve sending to the brain it's probably the case that there's no accidental

stuff sitting around in the retina that's Vis digal and sending information to the brain it's probably the case that this those signals are are all doing something important for our visual behavior for our well-being for our sleep all sorts of stuff and I think and the field is still trying to figure that out these these are the big Mysteries I think that in terms of the retina what are those signals exactly in all those different cell types what different behaviors and aspects of our life do they control what is the wildest cell type you've ever

encountered like what did it do like what did it respond to that's that's what I mean when I say wildest um you know it cells reog gangling cells that respond to you know increasingly red portions of the visual scene or decreasingly green portions of the visual scene like okay cool that seems cool like get some you know around the time of Christmas that that's useful and it's uh useful on other days of the year as well but you know given that the retina is indeed the best understood piece of the brain and given that you

have 20 cell types 20 isn't 20 million it's um you know it seems tractable probably gets understanding it in its entirety or understanding them in their entirety excuse me um one would like to know like what what stuff is are we paying attention to at the level of the retina I mean are there like Spiral sells it like Spiral stuff in the environment are there sells it like emojis like what what's going on in there you spent a lot of time doing this we do we SP a l after all you give up two nights

sleep which is kind of incredible by the way I'll just do a little uh take a moment here and just say you know for a guy that's been doing this for this long with these sleepless nights um you look pretty good you look pretty resty you I tend to go home I go home before The Graduate students do oh they stay up they stay up I was us to stay up I used to stay up until my mid 40s I was I was in there doing the all nighter type things got it and um maybe

you can help me figure out my sleep patterns better yeah yeah we can talk about that this episode we talk about how to pull all nighters and still survive done plenty of those um but yeah like what what's yeah lots at stake here there's a human retina you know meaning a human gave up their eyeballs to for this experiment after they died of you got many people on this these are these sort of experiments um are very expensive um a lot of fancy equipment a lot of salaries to try and figure this stuff out this

is the chief mission of the national eye institute there's a lot of tax dollars like this is um in my opinion as important as the Space Program probably more important in my opinion you know restoring Vision to the blind obviously so what are you finding in there yeah and and we have the privilege of being on the front lines of that funded by the National Institute and other in tions to be out there figuring out what's going on in this human retina I'm with you on that so I I'll tell you how we go B

it these days there are about seven cell types that we understand pretty well what they're doing they're it's not they're not complicated they just have different properties color size this kind of thing temporal properties their timing of their signals and those seven cell types we understand pretty well but we're trying to really nail down the details why because of neuroengineering for vision restoration then there's another I'm going to say 15 or so and we and the anatomists the people who study the shapes and sizes of the cells have long known that there were more cell

types lurking in the retinal circuitry but their function has not been known and because we didn't have many recordings from them we didn't have electrical recordings in response to light that would tell us what they naturally do we've actually had a breakthrough in the last few years led by a senior research in my in my lab named Alexander cing who has figured out that there's another 15 or so cell types lurking in those recordings that if we look more carefully they're there and they have crazy properties and so the crazy properties I can tell you

about have to do with the spatial region of the visual world that they respond to the well-known cell types that you know and I know from the textbooks kind of respond to a circular spot in the visual world if there's light in this little circular area they'll fire a spike if there's no light there they don't care well okay some cells is not quite circular some cells respond to the light that's there and and the difference from the light that's around it so if it's brighter than the light that's nearby then you then you get

a big response the new cell types are more puzzling than that some of them respond to three or four blobs in the visual world that's kind of strange unexpected definitely unexpected based on the textbooks and the newest ones are weirder yet some of them they're their visual response profiles that is the region of the visual world that they are sensitive to light in almost has a spidery shape almost like the dendrites of a cell like the processes of a cell and some of them have Blobby Light sensitivity they're sensitive to to light increments here and

decrements there and increments here and decrements there and some blue light over here and blue light over here we don't understand these cells to be clear the seven that we understand reasonably well well and not trying to just pin down and really nail for vision restoration the sort of first cut at at at cell type specific Vision restoration those ones don't have these weird properties they're a little simpler to understand so we're we're just but we're just working out all the details of the timing of the of the responses and all that these new ones

we don't know what's going on with them so we're doing experiments those seven cell types constitute maybe 70% of all the neurons that send visual information from the eye to the brain so we think it's a really solid Target for Vision restoration to work with the simple ones and so so when I when I say that I think that the retina is the best understood circuit in the nervous system I'm talking about those seven cell types which we know a lot about what they do we really do know a lot it's not done but we

know a lot I'm not talking about the other 15 cell types which are a minority of the population but seem to be doing very strange and surprising things that are yet to be determined so there it's a mix we know some really good stuff and then there's really some deep Mysteries out there about these other cell types so we've been talking a lot about how to understand the signals that the retina is sending the brain and I know your lab has done incredible work in this Arena and figured out a number of the different signals

as you described some of the features that the different cell types are extracting just a moment ago these Blobs of different colors Etc what good is this to you know the everyday person right um What What In addition to wanting to understand how we see you know what sort of sorts of medical applications can this provide in terms of potentially restoring Vision to the blind um but perhaps even larger theme is this notion of neuroengineering right taking this information and creating devices that can help us help our nervous system function better maybe even function at

superphysiological levels I know there's a lot of interest in this these days um in part due to neural link right because elon's out there front-facing very vocal about his vision of the no pun intended of you know chips being implanted in people's brains that would allow them to be in conversation with you know 100 people at the same time just by hearing those voices in the head maybe filtering things out so it doesn't sound like a clamor of a hundred different voices um perhaps giving people super memory I mean you know sky the limit no

no one really knows where this is all headed you're working in what we call a very strain system where it has specific properties that you're trying to understand and once you understand those you can start to think about real applications of like what's possible like could you create a visual system that um Can extract more color features from the world that no other human can see um can you restore um pattern Vision to somebody who is essentially blind independent on a cane or a dog or you know God forbid can't even leave their house because

they can't see anything at all you know where is this headed what is the information useful for and perhaps we should frame that first within the medical rehabilitative context of repairing uh or restoring Vision rather and then get into the more kind of um uh sci-fi type neuroengineering stuff absolutely yeah this this really is my passion these days turning that corner continuing to figure out the mysteries in the retina but also saying wait a second we actually know quite a lot about this shouldn't this be the first place that we can solve problems like restoring

Vision restoring function or augmenting our function I think it should be the concept of how to do this is straightforward and not invented by us in any way and that is the following one of the major sources of blindness in uh the Western world is uh loss of the photo receptor cells that capture light macular degeneration and retinitis Pigmentosa are two well-known ailments that give rise to to vision loss and the vision loss is because the cells that capture light in the first place that we talked about earlier die off so you're no longer sensitive

to light and then you're blind the concept is that you may be able to bypass those early sections of the retina that capture the light and process the signals and instead build an electronic implant that connects up directly to the retinal ganglin cells and this electronic implant would would do the following it would capture the light using a camera which is relatively easy it would process the visual information in a manner similar to the way that the retina normally does as similar as possible and then it would electrically activate the retinal gangin cells by passing

current and causing the gangin cells to fire spikes and send those spikes to the brain and if we do this really well we can essentially replace those first two layers of the retina and piggy back onto the third layer and say okay we're just jumping right into that third layer we're going to force those ganglin cells to send reasonable visual signals to the brain and then the brain is going to think it got a natural visual signal and proceed accordingly that's the concept this is not our idea people have had this concept for decades and

some people have even started to make it work in in human patients and what I mean by that is implanting electrodes on the retina stimulating and causing people who've been profoundly blind for decades to see visual sensation blobs and streaks of light in their visual world that that are reproducible so so that's happening now that's happened people who were at once blind yep are able to see objects are able to see crude blobs and flashes of light in ways that allow them to navigate their world better a little bit a little bit avoid a coffee

table maybe or at least see a bright window in a dark wall and be able to point to that bright window or the bright doorway in a dark wall something like that so it's a glass half full half empty story that I want to turn that I'd like to turn attention to in this conversation cuz I think it's very exciting um yes you can see stuff by artificially electrically stimulating the ganglin cells and you can see stuff that actually helps you interact with your world a tiny little bit so great that's the glass half full

the glass half empty is it's nothing remotely resembling what we understand as naturalistic Vision where we see spine spatial detail and color and objects and can navigate complex environments and all that stuff no chance you can't do anything remot remotely like that you can see that there's a bright doorway over that way and turn toward it which is a helpful step in your Human Experience but there's a long way to go so the question is why does this existing technology fail to give us high quality Vision what what's needed to give us high quality vision

and this is the piece I'm really passionate about it turns out that the the devices that have been implanted in humans so far by pioneering bioengineers who did really hard stuff were were fairly simple devices that treated the retina as if it's a camera that is just a grid of pixels and they put a grid of electrodes down there and they stimulated it according to the pixels in the visual world and thought well hopefully that will cause the retina to do the right thing and send a nice visual piece of visual information to the brain

and initiate Vision Unfortunately they left the science on the table and this is actually what I'm dedicating the next phase of my career to bringing the science that we know that we talked about to the table for vision engineering and in particular the fact that there are there really are 20 or so distinct cell types and they send different types of visual information to the different targets in the brain I like to think of them a little bit as uh an orchestra playing a symphony each different cell type has its particular score the violins do

one thing the obos do something else it's a very organized signal coming out of the retina presenting to the brain this complex pattern of electrical activity that the brain assembles into our visual experience well current retinal implants unfortunately are too crude to do anything like that the the conductor has just scattered the sheet music everywhere and people are playing whatever it's cacophony okay you can maybe recognize a tune in there a little bit sometimes navigate toward a doorway but you're not going to get the full richness of the experience by ignoring the different cell types

and I'm so passionate about this in part for reasons that a little bit are similar to your reasons for doing this kind of work that you do which I think is great which is I I feel we have a mission to give back as scientists to take all this stuff we've been talking about because we find it so interesting and cool and to deliver something to the society that has allowed us to explore these fascinating areas and in our case it's in my the case of my lab and what we've done it's to turn around

and say wait a second we understand that there's these different cell types we understand a lot about what they do none of this information appears in current epir retinal implants can't we do better by using the science to restore Vision in a way that respects the circuitry of the retina that's what we're trying to do and the mismatch is intense um I I told you when we were adding before that nothing that we have learned about the retina since the founding of the national Eye Institute in 1968 is incorporated into the existing retinal implants nothing

we've learned a ton about the retina your research was funded by the national Eye Institute my research is funded by national ey Institute a fantastic organization that allows us to learn all these things how is this showing up in the neuroeng engineering to restore Vision to people well currently it's not and so we're trying to do that now doing that turns out to be hard and maybe we'll talk about that it's a it's a technological feat that's really challenging you have to build a device that you can implant in a human that can recognize the

distinct cell types see where they are stimulate them separately from one another and conduct this Orchestra to create a musical score that reasonably closely resembles the natural one that's what we're all about doing and as it turns out and maybe we'll talk about that separately that mission of being able to restore the patterns of activity that the retina normally creates also has extremely exciting spin-offs in three directions one of them is understanding better how the brain puts the signals together that's research for the brain the second one is augmenting Vision creating novel types of visual

Sensations that weren't possible before and maybe doing something along the Elon Musk lines of delivering more visual information than was ever possible and third figuring out how to interface to the brain more broadly because as you and I know the structure of the retina is very much representative of the structure of many brain areas and if we're going to figure out how to interface to the visual cortex we darn well bitter figure out how to interface to the retina first that's what we're all about doing in my lab these days is figuring out how to

do that well that's a mixed science and Eng engineering effort we've done about 15 years of basic science on that how do we stimulate cells how do we recognize cells how are we going to build a device that does all this and talks to the cells in this way and I can go into lots of gory detail about it um but that's what we've been doing the basic research on and the last few years we've worked at Stanford with um fantastic Engineers from various disciplines electrical engineers material scientists others to figure out how to put

together the pieces and build an implant that can do this in a living human so is the idea to build a robotic retina to build a a essentially an artificial retina that could be put into the eye of a blind person or even put into the eye of a sighted person that would fundamentally change their ability to see or in the latter case uh enhance their ability to extract things from the visual world that they would otherwise not be able to see like like seeing twice as far um getting you know hawk-like resolution of the

visual World um yep or which that would be cool yep could be distracting yep like I'm not sure I want to see the the fine movements of a piece of paper in somebody's notebook from across a cafe as they flutter the pages um but you might want to for a moment there might be a moment when you want to and if you have an electronic device that you can control that you can dial in to sense different aspects of the visual World Under You Know by by your choice you might be like yeah that's pretty

cool I want to be able to do that right now there's an example I like to give which I think maybe is is helpful for interpreting what we're talking about when we say being able to do more things with the optic nerve you gave the example of many voices and stuff here's an example that I like we know that we can drive down the road and have a phone call handsfree and do that quite safely pretty safely right and you're why because you're tapping in you've got two types of signals coming into your brain your

visual signal of the cars on the freeway any one of which could kill you in an instant so it's important and the sound coming into your ears which carries the voice of your girlfriend that's telling who's telling you something that you're interested in hearing and these are different parts of the brain processing this information and so you can do both of these things at the same time because there's no interference one part of the brain is working doing one thing another part's doing something else you're good what you can't do is to read your texts

and drive down the freeway at the same time that's not good because now that visual system of yours that needs to be detecting these fast moving dangerous objects is being distracted by looking at the text and you might die and some other people might die with you so I see a lot of people texting and driving yeah that's why I like to point out this example to remind people you can't do it well it's like it's like can't do it well you probably talk yeah it used to be you know we'll just take a brief

uh tangent here into this topic um a few years back there were there were a lot of news articles a lot of discussion about texting and driving a lot of attention to getting people to stop texting and driving I've seen a few people pulled over for texting and driving before but I would say texting and driving is rampant reading what's on one's phone y while driving is rampant yep all you have to do is be on the freeway here in Los Angeles look in the car next to you yep look where they're looking and people

like reading and texting while driving presumably when they're doing that they're just using their peripheral vision to detect any kind of motion and um no doubt this has caused the deaths of many people yeah change lanes get away from them and you know just just like that other driver so so here's the thing um and this is this is uh I say this a bit tongue and cheek but it's it's sort of a real example it may be that if we harness the different cell types in the retina to deliver different visual information to different

cell types like the image of the text on your screen to a certain cell type that you know the so-called cells or the motion of the objects in the visual scene the cars to a different cell type cells by the way folks because they're very very small yes and by named by anatomist decades ago so we carry that nomenclature forward sure um and the parasol cells which are different cells that you can potentially encode the movement of the cars in the parasol cells and if those two systems are operating independently which we sort of think

they may be from research that you know very well from your extensive studies and vision um maybe we can do those two things safely at the same time now by the way that's not my research goal to text and drive at the same time just to be clear but it's a very tangible real world example of if we do really have parallel Pathways that can be modulated and controlled independently of one another this opens the door to streaming all kinds of visual information in parallel into our very high band with visual systems that wasn't possible

during Evolution because we didn't have control over the cell types so I think of that as the world of visual augmentation and it starts to get interesting if the different cell types are behaving in an independent way and when they transmit visual information to the brain now how are we going to figure that out well we need a device that can stimulate the different cells independently and then study that to see whether people can and can do this kind of thing right what's that device the artificial retina the same implant I'm telling you about that

can restore Vision to people because it's an electronic device that can up in the activity in the different cell types that same device is what we can use as a research instrument to understand if the different pathways are parallel if the signals interact with one another and explore how the brain receives that information and then we can use that to explore can we augment vision and allow allow ourselves to have new visual Sensations that we don't even know what that would look like we we we don't even understand what it would look like to us

to see those Sensations but it might be able to deliver lots of information to our brain and if we can do all those those things then we can take that same set of tools and Engineering Technologies into the brain to access different cell types as well I'd like to just take a quick break and acknowledge one of our sponsors insid tracker inside tracker is a personalized nutrition platform that analyzes data from your blood and DNA to help you better understand your body and help you reach your health goals now I've long been a believer in

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the ranges that are optimal for you insid tracker also offers insid Tracker Pro which enables coaches and health professionals to provide premium and personalized Services by leveraging inside tracker's analysis and recommendations with their clients if you'd like to try insid tracker you can go to insidetracker docomo and you'll get 20% off any of insid tracker's plans again that's insidetracker docomo here of of what you've done um you started off with the understanding that the neural retina is perhaps the best place to try and understand how the brain works because of its Arrangement the cell types

Etc you spend a number of decades doing these wild experiments um on human retinas and other retinas um recording the different cell types with these highdensity What I Call Bed of nails two and a half decades I'm not that two and a half decades um it's your uh robustness that matters EJ um and you have plenty of it um you figured out what the cell types are so then you gained an understanding of how light is transformed into different types of electrical signals that encode different features in the visual scene then comes the challenge of

developing neuroengineering tools to try and stimulate the specific cell types in a way that more or less mimics their normal patterns of activation like not um activating a huge piece of retina so that you know the cells that like increases in redness are also being stimulated with the cells that like you know edges in a way that would create some shoy like crazy representation of the outside world no you want the same Precision that light stimulation of these cells in the intact human eye provides in this explanted retina this retina on this bed of nails

but then a device that essentially can mimic what the retina does and you needed to do all that earlier work understanding like what does the normal retina do what does the healthy retina do in order to try and develop this prosthetic device to either restore Vision or because it puts puts you in the position of being able to stimulate cells however you want in theory you could create a situation in a human where the cells that respond to um I don't know outlines of objects are are hyperactive so that you know the person could um

effectively see objects in one's environment better than anyone else yeah could perceive I know motion is a tricky one but motion better than anyone else could see detail in the visual world that no one else could detect we're not talking about turning people into mantis shrimp um but the analogy works because mantis shrimp can see things that we can't and vice versa and so what you're talking about here is neural augmentation through the use of engineering yep and we often do talk about it as sci-fi because the Sci-Fi writers have been talking have been you

know writing about this for decades it's not sci-fi anymore it's sigh it's straight up sigh right now it's really we just need to build the instrumentation and start working with those experiments to figure out how to make make it work I think we have a responsibility to do this because this is the way we take this kind of information all that's been learned about the visual system by the national Eye Institute since 1968 and all the people that it's funded to do this research and turn the corner and make a difference for Humanity with it

and I I assume and think that Humanity will be leveraging nervous system knowledge to build all sorts of devices that we can interface to the world with I think you know I don't know Elon Musk but I think he's right about that that that's where we're headed it should be done well it's important to do it well um we will hopefully be more connected to truth in the world if we're able to build devices that give us better Sensations more acute understanding of what's going on out there better abilities to make decisions and all that

let alone just see stuff so that Frontier of developing Technologies to allow our brains and our visual systems initially and then other parts of our brains to do things better is unbelievably exciting it is SciFi but I just want to emphasize I think it's the responsible way to go to think about how to do that well all technologies that we develop can be used for good or for ill and I'm sure some of your listeners who are a lot a lot of very passionate thinking people out there thinking about neuroscience and the implications worry what

does this mean we're going to be introducing electronic circuits in our brains to do stuff yeah well we will it's pretty much clear that Humanity will do that and so in any technology development you have to think about well how do you do it well how do you do it for good there there are popular movies right now about technology development such as understanding the structure of the atom and that technology development can be used for good or for ill to blow up cities or to save civilizations how's it going to go well I think

I think as scientists we're responsible for advancing that in a thoughtful and meaningful way I think we can do this in the retina it is the place to start it's the and you know you I'm curious what you think actually as a scientist your background is in this field or very close field to mine I know you speak with all sorts of scientists on this podcast um but this is pretty much your field or very close not the neuroengineering part but understanding the retina I'm curious if you agree that this is the place to start

doing this stuff the first guest ever asked me a question on this podcast during a guest interview um I think this would be a fun place to both answer and Riff on this a little bit because um first of all I think the retina is absolutely the place to start because we understand so much of what it does what the cell types are but maybe by comparison a different brain region the hippocampus which is involved in the formation of memories and other stuff but formation of memories about what one did the previous day what one

did many years ago Etc is an area that I think anytime the conversation about neural Prosthetics or neuroengineering or neural augmentation comes up people think oh wouldn't to be cool to have like a little stimulating device in the hippocampus and then if I want to remember a bunch of information from a page or from a a lecture I just stimulate and then voila all the information is batched in there um while that's an attractive idea I think it's worth pointing out right now that sure there is a pretty decent understanding of the different cell types

in terms of their shapes some of their electrical properties of the hippocampus but there is in no way shape or form the depth of understanding about the hippocampus and what the individual cell types do and what the different layers of it do that one has for the neural retina so what we're really saying is if you stimulate the hippocampus you'll likely get an effect but it's unclear what the effect is and it's not clear how to stimulate that's to me the best reason to focus on the retina because you know what the cell types are

thanks to the work of your laboratory and many other Laboratories you know what sorts of stimulation matter and it provides the perfect test bed for this whole business of neural augmentation neuro neuroeng engineering I think there's also a bigger discussion to just frame this in which is so much of what we discuss on this podcast with guests and in Solo episodes relates to things like dopamine neur neuromodulator serotonin and everyone is interested in these things because they can profoundly change the way that we perceive and interact with the world but one only has to look

to the various Pharmaceuticals that increase or decrease these neuromodulators and know that indeed those Pharmaceuticals can be immensely beneficial to certain individuals I want to be clear about that but that whatever quote unquote side effects one sees or lack of effect over time is because those receptors are like everywhere over the around the brain so you can't just increase dopamine in the brain and expect to only get one specific desired effect so the reason you're here today um is not because we both worked on the retina and it's not because we happen to also be

friends it's because uh to my mind your laboratory represents the um Apex of precision in terms of trying to figure out what a given piece of the brain in your case the neural retina does parse all its different components and then use that knowledge to create a real world technology that can actually tickle and probe and um stimulate that piece of the brain in a way that's meaningful right not just like sending electrical activity in and that to me is so important I think if we were going to think about levels of specificity for manipulating

the human brain to get it an effect you would say okay crudest would be drugs take a drug increases serotonin which might bind to particular receptors let's take the drugs psilocybin a lot of excitement about psilocybin we know that can lead to increased connectivity between different brain re at rest there's probably there is some demonstrated clinical benefit there's also some potential hazards but it's very broad scale we don't know what's happening when the person is thinking about a uh you know a piece of moss expanding into an image and a memory of their childhood or

it's like a million different things are happening there and then at the other far extreme is the kind of experiment that you're talking about stimulating one known type of retinal cell seeing what that means for visual processing or modeling what that means means for visual processing and then building a device that can do exactly that and then maybe ramp it up 20% 50% and because I think that represents the first step into okay how would you stimulate the hippocampus to create a super memory would you stimulate a particular cell type in a particular way and

to my knowledge There's You know despite the immense excitement about the hippocampus and understandably so there just isn't that precision and of understanding yet so uh forgive the long answer but you know you ask me a question on on this podcast give you a long answer yeah and it specificity is what you're talking about and we need technology to do that to to modulate neural circuits in a highly specific way we got to start with the piece of the neural circuit we understand best and we have best access to that's the retina it's sitting right

there on the surface we can get right into it and in install devices we know so much about it that's the place to start the place that we understand build Electronics that is that is adaptive that senses what circuit it's embedded in and responds appropriately it's not just Electronics you stick in there and it does something and that's it no it it first figures out who it's talking to and then learns to speak the language of the nearb neural circuitry so a smart device smart device let's push on that a little bit so um put

a little chip onto the retina that can stimulate specific cell types is there a way that it can use AI machine learning that it can learn something about the tissue it happens to be in contact absolutely in the simplest possible way the device Works in three simple Steps step number one record electrical activity which is what we do in our lab in a room full of equipment but this is a 2mm size chip implanted in your eye record the electrical activity just recognize what cells are there when they're firing what electrical properties they have to

identify the cells and cell types in this specific circuit in this human that's step one step two stimulate and record so you figure out oh this electrode activates cell number 14 with 50% probability this electrode activates cell number 12 if you pass a micro amp of current with this probability and so on you make a big table that tells you how these electrodes talk to these cells in your circuit that's step two calibrate the stimulation by stimulation and recording then finally when you have a visual image and you want to represent it in the pattern

of activity of these cells you say okay I know from Decades of basic science what these cells ought to be doing with this image that's coming in I know exactly what they ought to be doing that's what the science has been telling us we've been studying the neural code for decades to understand this I know what they should do use my device with my calibration where I know where the cells are I know how the electrodes talk to them and bing bing bing bing bing activate them in the correct sequence that's what I think of

as a smart device a device that records stimulates and records and then finally stimulates yes AI is part of that of course it is because this is a very complex uh transformation if you will from the external visual world to the patterns of activity of these cells it's not easy to write down in just a few lines of code or in a few equations it's complicated and AI is really helpful for that and learning by stimulating and recording and aggregating information quickly so that you can then use the device that's absolutely a part of the

engineering it let me be clear the AI doesn't help us to understand it's just an engineering tool that helps us to capture what this thing normally does and then go ahead and execute and make it do the thing it should normally do I hope people um will appreciate this example uh perhaps not you know not but goodness I don't know 40 50 years ago but still today uh one treatment for depression is electric shock therapy uh a very you know on the face of it barbaric um treatment but effective in certain conditions it's still used

for a reason um but it can appear barbaric right you know people are have like a bite you know a bite device you know so they don't um bite through their tongue or their lips they're you know they're strapped down and they stimulate the whole just like stimulate all neurons in the brain essentially there's a huge dump of neurotransmitters and neuromodulators it's like drugs it's completely non-specific stimulation effectively probably even less specific than drugs maybe and yet the clinical outcomes from electric shock therapy in some cases are pretty impressive like people um the brain is

quote unquote reset they still remember who they are um but presumably through the the the release of neuromodulators like dopamine serotonin acetylcholine in a very non-specific way there has been some symptom relief in some cases what you're talking about is really the opposite extreme um you know before I said Pharmaceuticals that tickle a particular neurom modulator pathway would be the opposite extreme I think electric shock therapy is probably the the the most um extreme where is this whole business of neural prosthesis going outside of the visual system like right now um I can imagine that

there are little stimulators in the spinal cord for sake of restoring movement to paralyzed people um I realize this is not your field but is are you seeing impressive stuff there um or is it still really really early days there's absolutely impressive stuff uh particularly uh for example people reading out signal from the motor cortex or the language cortex in order to help people to communicate or to move cursors on screens in order to interact with devices these are paralyzed people par yeah excuse me paralyzed people who can't interact with technology the way that we

do um and but with their thoughts can send signals through an electronic device that can be used to control a mouse on a screen and have them connect to the internet that's a huge deal to be able to have people do that imagine how life changing would be to be able to communicate if you couldn't before so there are wonderful examples of that you know of them so do I the work of Krishna shinoy and Jamie Henderson at Stanford is one beautiful example over the recent years Eddie Chang doing stuff now uh you know neuralink

doing doing this kind of stuff the built on the work of Shino and Henderson and stuff so that's great um you know stimulating in spinal circuits as you said for creating rhythmic movements that's that's happening so this is an enormous space and in each case what you said I think is really highly relevant that electroshock therapy you can think of that as look let's say your computer is not behaving right you can reboot it might work then it'll start not working again then you have to reboot it again well how often do you want to

reboot your computer it gets a little inconvenient to be rebooting your computer every five minutes maybe you want to go in and actually diagnose this thing and put in a piece of software that fixes the thing that was going wrong instead of rebooting your computer every 5 minutes right and I think of electric shock therapy a little bit as a reboot um it's that level so we want to intervene more specifically how do you do that well you have to understand the software in order to do that you have to have specificity controlling this thing

in your computer not this this this this or this this particular thing that's going wrong you got to interfere with that and change it and modulate it well that's what understanding the neural circuit is about that's what building specific Hardware that can activate specific cells is about that's in in the case of the retina again it's just so obvious that it's right in front of us to do this stuff and it's right in front of us to take us into augmentation to giving us better senses a fun example I like this is it's an interesting

topic because the National Institutes of Health that um funds a lot of research that goes in this direction tends to not be interested in augmenting our senses they kind of want to they they draw a line more or less saying look we're trying to restore what we were as humans not create a new kind of human and that's an interesting question because I don't think there is a fine there's an actual line a bright line between those things I don't think there's a bright line between those two things the the finest example I know is

that even in the very crudest visual restoration devices you have to actively suppress the infrared sensitivity of your camera to not have infrared vision why because many cameras are sensitive to infrared light so in other words if you don't put an infrared filter in front of your camera you're going to have some infrared vision maybe it won't help you very much whatever I'm just trying to say as soon as you start building devices to restore Sensations building electronic devices augmentation is right around the corner it'll creep up on you real fast so I I think

you can't even really draw a line throughout today's discussion we've been thinking of the brain as kind of a the rest of the brain I should say because the neural retina is two pieces of the brain extruded out into the eye Globes during development I like to remind people of that over and over when you're looking at somebody's eyes you are looking at two pieces of their brain um there no debate about that but most people don't realize that you'll never look at anyone the same way again but this is the reason why you can

tell so much about people's inner state from their from their eyes somebody who's sleep deprived it's not just about the droopiness of their eyelids or the circles under their eyes there's a there's an aliveness to the eyes the the yogis um talk about um people that sort of show up at the level of their eyes as opposed to sunk back into their brain you know these are very um kind of abstract Concepts but they and there's some very non-abstract stuff these days looking at looking through the eye at the retina the way the op opthalmologists

do and there's a lot of diagnostic capability just in those images of the rtina oh right there I'm glad you brought this up there's um some uh interesting and increasing evidence that looking at the neural retina because it is a piece of the brain with neurons that have the potential to both Thrive or degenerate that looking at the neural retina which one can do with these new technologies um can provide a window into um whether or not there are forms of degeneration just such as Alzheimer's and other forms of neurod degeneration deeper within the brain

that one can't image directly because of the the thick opacity of the skull right so in other words Imaging the eye in order to determine if someone is developing V in Alzheimer's because you have a direct view into a little piece of the brain it's a it's a good signal it can help you figure stuff out about what's going on in your brain even beyond the sunken eyes absolutely amazing so I think the rest of the brain piece is is also really interesting and maybe here we can go like semi neuro philosophical um you know

that there are clearly parts of the brain that are involved in um essential what I call housekeeping functions regulating respiration you know keeping us breathing keeping our heartbeating um digestion um responding to threats in in some sort of basic way like through the secretion of adrenaline and and giving us the potential to move but a lot of the brain is is um capable of plasticity and um one wonders if you were to for instance develop a retinal prosthesis that would allow me to um see with twice the level of detail that I currently can would

my adult brain be capable of dealing with that information we're talking about twice as much information coming in same brain tissue on the receiving end can it make sense of it do we have any idea if it can make sense of it are there um are there experiments that speak to that yeah that's a fantastic and interesting question it makes you think about neural development all over again right and I I take some inspiration on that from the work of someone you know Eric nson um who discovered that there is plasticity beyond the period periods

of time he discovered many wonderful things but there's plasticity well beyond the period of time that we thought that there was plasticity in certain animals and in particular that if you make gradual adjustments to the sensory world you can exhibit plasticity that you can't see if you make an Abrupt adjustment so plasticity is there it just has to be brought on by more subtle manipulations that take you from A to B in little incremental steps and if you take those incremental steps you can see the adult plasticity so coming to your question is the brain

capable of receiving the kind of extra information we provided could be that if we just show up on day one bam try to deliver twice the visual resolution or whatever in your visual your visual system it could be that if we try to deliver twice the visual resolution on day one it won't work you'll see It'll you know it won't look sensible to you but if we gradually introduce it by the way that we're dialing up the resolution we may be able to get there and there are fascinating studies to be done you think about

Spike timing dependent plasticity a term that that your viewers may not all know but is a is related to how neurons adjust their strength of connectivity to one another according to the timing of the signals in those cells mechanisms like that tell us wow the brain really cares about the very precise timing of stuff and to the degree that that influences the way that neurons do or don't strengthen their connections to one another it's so fundamental in everything from memory to visual function what have you this relates to fire together wire together although um it

highlights the Together part how closely in time do two neurons need to be active in order for them to subsequently increase their connectivity and indeed one of them needs to be active a little bit before the other one in order for it to work optimally right so if it what I what I Envision is that when we have full control of the neural code with an electronic implant that can talk to the cells and do all the things that I said and we can really control the neural code coming out of the retina we can

then start to play games and dial up that neural code very slowly and teach the remaining brain how to understand these signals not introduce some crazy thing from day one no just gradually teach isn't that how we do everything well isn't that how plasticity works I love the uh subtlety and the uh rationality of your example because you know so much of what we see in the internet and on the news is like you know chips inserted into the brain to create super memory or uh you know conversations between you know 50 people at the

same time without anyone speaking you know just hearing other people's Thoughts by way of um you know neural signals being passed from one to the next but yet another reason why you're here today is because you represent the the the realistic grounded um incremental approach to really parsing this whole thing of how the brain works and how one then goes about um engineering devices to augment the human brain and as you just pointed out it's not going to be done by just sticking electrodes in and stimulating and seeing what happens in fact those experiments were

done in the 1960s people like Robert Heath would put electrodes into the brain during neur surgery stimulate and just see what the patient would do or what they reported thinking you know nowadays that's done still but with a lot more precision and intention and we've moved we've moved far beyond that by the way I just want to say those were important first experiments the first thing got to do Keith was was was a rather um let's be honest not not the most Savory character he he embarked on some experiments that um had a social agenda

to them and was a pretty pretty uh at least by my read was was not the kind of person I'd want to spend time with to say the least but but you're right those experiments were critical because like electric shock therapy like the formulation of drugs that can massively increase certain neurom modulators or decrease them they LED to some level crude but some level of understanding about how the brain works which is what we're really talking about today yep um but you represent the uh as I said the the astronauts of this astronauts don't go

into space and just kind of blast off and see where they end up there's a there's there's math there's physics uh there's computer science sensors cameras right looking where are we about to land here on the moon is there a crater here or not what what's around us we we should sense what's there and then make our decisions accordingly and our electronic implants in the brain really we should make them smart why make them dumb we're smarter than that we can build implants that can sense what's around them and change their patterns of activity accordingly

I I use a metaphor sometimes if you go to if you go as an American who doesn't speak Chinese to China and you start yelling in English maybe somebody will to to learn which way to go on the street somebody might understand you at some point and help you out but it's going to be a it's going to be a you know not very effective way to get around it's way better if you speak the language you talk to people and ask ask them where to go so that's what we need to know we need

to say look we have the science we have incredible devices we can engineer we have ai now that even helps us to do this query of the outside world and turn it into a smarter instrument make our instruments smart make them so they know how to talk to the brain don't expect that the brain is just going to wrap itself around your your simple electronic device no make a smart device that's what we want to make a smart rental implant maybe we could just take a couple of minutes and talk a little bit about you

and the some of the things that have led to your choice to go in this direction so did you always know you want to be a neuroscientist from the time you started college what was your trajectory I should know this but I you were an undergraduate at at Princeton at Princeton that right studying math math so you could have just done all your work with a piece of paper and a pen but you had to try and engineer all these electrodes okay that's a pen and paper pen I took a very random route I studied

math as an undergrad I spent a few years running around playing music and traveling living a Bohemian life well tell me more about that oh it was I basically just told you all I'm going to tell following the Grateful Dead no not quite following them but uh it was that was an important part of the story um and important part of your personal development um yes very much so uh free Expression Dance music creative exploratory music all that kind of stuff such a contrast to the the EJ that comes forward when we're talking about the

Precision of neural stimulation in in the in specific retinal cell types but I think it's useful for people to hear both young and old like um that uh one's nervous system can be partitioned into these different abilities like go and dance and travel and you you weren't doing anything academic at that at that time no for a few years I wasn't doing that programming computers to make a to make a living and uh then I started I started three different PHD programs at Stanford before I simultaneously no no no in sequence I started in the

math PhD program I learned that was not really for me and I started in a in an economics PhD program in the business school there and I realized after after less than a year that was not for me um I worked in a startup company for a while I did a lot of stuff for a few years and took some settling um but then I decided to go into nurse science and there were a couple formative things one is that I had I had gotten a really formative experience as an undergraduate from a wonderful guy

called Don ready who taught a introductory Neuroscience course who was really inspiring Mentor um and then when I when I was at Stanford I met Brian wandell my PhD adviser and I was inspired by him I thought I didn't know why he was studying what he was studying but I just knew I wanted to learn from this man and I wanted to study with him I just knew this was this was the person who should be my mentor based on something about him yes C can I ask you about these three PHD programs because I

think people here um you know or or see what you're doing and and probably imagine a very linear trajectory but now I'm hearing you you like tour it around playing music then you start a PhD program nope then another one nope then another one without getting into all the details I mean were there nights spent lying awake thinking like what am I going to do with my life or did you have the sense that you knew you wanted to do something important you just hadn't found the right fit for you like how how much anxiety

on a scale of 1 to 10 10 being total panic um did you experience at at the Apex of your anxiety in that kind of wandering am I allowed to go above 10 like turning up the amp to 11 sure I just think it's really important for people to hear whether or not they want to be scientists or not this idea that people that are doing important things in the world uh in my view um um rarely if ever understood that that's the thing that they were going to be doing there was some wandering about

that sure seems like it doesn't it yeah I I I experien the same when I talk to other people and it seems like that and for sure for me uh it just took a while of trying different things to see number one what I was really good at and where I felt I could make a difference and it and I realized um I studied math and I was okay at math but I know I I have known mathematicians who are really talented gifted mathematicians the one who really make a difference I wasn't going to be

one of those people likewise playing music I don't have that intrinsic Talent it's fun I can play songs in front of people and do stuff I like it and stuff like that but I don't have that kind of talent in fact I'll say something that that I say to friends sometimes and you're a good friend of mine if I had the talent to get a few thousand people on their feet dancing by playing music I'd probably just do that really as long as we've been friends I knew none of this I like knew none of

this mostly because I think we always end up talking about Neuroscience or other aspects of our life yes um but I I didn't know I know I know a great many things about you but I had no idea it's so interesting um do you still do dance we had Eric Jarvis on the podcast by the way Professor Rockefeller who studies um at one point was studying um uh Speech in so in Birds um and song in Birds and then he's done a great many other things now in genetics of of vocalization and you know he

actually uh danced with or was um about to dance with the Alvin ay Dance Company it's like a really really talented dancer um and so you know dance seems to be like a theme that comes up among the Neuroscience guests on this podcast do you still dance yeah I love to dance I'm a free form dancer I don't I'm not a skilled dancer but I love I love music I love dancing I think it's part of the human spirit I someday will understand the Neuroscience behind dancing Dan in right dancing is a universal human thing

in all cultures what is this dancing thing why do we do this and other creatures don't well Jarvis thinks that um perhaps it's one of the more uh early forms of language and that song came before spoken language it's sort of interesting that birds that um can actually recreate human speech oftentimes have the ability to dance as well oh wow um and and so there's some commonality of circuitry there we'll provide a link to that episode jar really I would love to hear that I mean I but if I may I just I'd like to

Riff on that in a different in a different way um I did spend some time wandering around as many people do um and I think particularly for your young listeners and viewers who don't know wow you know could I ever be a scientist and develop new things stuff like that yes you can and if you're messing around your life trying this trying that trying the other thing definitely stick with it keep looking for the thing that works for you I I really deep believe that you got to play around you got to find what it

is that works for you interestingly enough at least it's interesting for me I I spent a lot of years studying the retina in a pure basic science just curiosity driven research way as you and I have both done in the past um and as it turned out I learned all the stuff I needed to know about the retina to do to develop a high fidelity adaptive retinal implant of the type that I'm talking about in that process the technology the stimulation recording figure out the cell types how do you stimulate all stuff I learned all

that stuff and I have come to a point in my life where I realize wow if somebody's going to do what I think needs to be done which is to take everything we've learned about the retina and instantiate that in in smart technology that can restore vision and do all the things we've been talking about who who are the people in the world who have the right training and background and knowhow to do that stuff I I'm one of them I I know that and it's totally by chance that I picked up and learned or

it seems by chance that I picked up and learned the things that I need to know for this so but but I'm I definitely have the right knoow to do this based on all my training and the research that I've done and it feels accidental sometimes I look back on my own history I'm like how did I get here where this is obviously the thing I need to do was this this on purpose it didn't seem like it was on purpose but now I got to do this because I know what needs to be done

and it's something that needs to be done so that's that's my mission for the you know coming decade or so wild I I mean I knew you had this engineer matthy uh geeky Neuroscience I don't want to say geeky cuz I'm well because it makes it sound like I'm not right there in the same same uh raft with you but but I didn't know about this more free-spirited um move in all directions depending on what one feels the moment dancing uh EJ it's very cool um are you still a a absolute level 11 coffee snob

yes okay yeah I used to go to meetings and um EJ would bring his own coffee maker and coffee to to meetings we're not talking about an espresso machine we're talking about like extreme levels of coffee snobbery press pot the correct ground coffee correct kind of press byot good good good I I expect nothing less uh proof that um not all circuits in the brain are neurop plastic nor should they be that's right but to bridge off of that in a more serious way um despite the the free you know free exploration aspect to yourself

and and that hopefully other people don't suppress um it seems like you you really are um good at develop like knowing your taste like it seems like the the I think it was the great Marcus Meister a colleague of ours who you know has also worked on the neural retina extensively of course once said you know that there's a coding system in the brain that leads to either the perception the the feeling of um yum yuck or me and that so much of life is being able to register that in terms of who you interact

with and how and um the the choices of problems to work on it seems like you have a very keen sense of of like yes that and you move toward that you've always been very goal directed um since the time I've known you so and and you've picked such a a a huge problem but going about it in in such a precise way hence the the analogy to the space space mission so um like when you experience that um may ask is it does it come about as like a thought like oh yeah that has

to be the thing or is it like a whole body sensation what a great question I love that question I have two things to say to that the first is that for me it's all it's all feeling I I don't make hardly any decisions out of thoughts I think I process I put it all into the hopper and the hopper comes out and spits out a feeling and feeling's like yeah that's the thing to do 100% And I know not everybody's like me lots of people aren't like me and particularly lots of scientists aren't like

me that you know so but but I definitely roll that way that is absolutely how I work there's there's something that's related to that that I think is you know philosophically in terms of personal development and Spiritual Development stuff I think is quite relevant that I think you'll you'll relate to my favorite aphorism is know thyself the Oracle and I I think because if you don't know yourself you can't do anything you don't even know where to go you can't even you know Orient yourself at the next thing in your life and I think it

deserves to have um two Aries that go with it or aenda uh know thyself be thyself which is not easy it's not easy to really be yourself in this world there are all sorts of things telling us to be something other than what we are and the third one is love thyself and it's you know having gone through much exploration of yourself and your life and your values and my and me too and all the things we've talked about over time that's not easy some of us are not necessarily programmed to love ourselves and uh

it's a skill I and I really I try my best to be with those three things all the time know thyself be thyself love thyself could you elaborate a little bit more on your process for the third I this is a concept that um has been very challenging for for me and I think for many other people um and it gets um kind of opaque when it starts getting complete with like self-respect and and Etc like like loving thyself do you have practices um do you meditate um do you Journal do you spend time um

trying to cultivate a love for self yeah yeah I'm I meditate in an informal way in the morning with my coffee every morning I make a fantastic cup of coffee and I sit with it I believe you for five or 10 minutes and take in my world as it's coming toward me and start to be as I as I come into the day and come into Consciousness I I I meditate like that and I have a aanga related yoga practice many of you many of your viewers and listeners will know about Ashtanga Yoga it's a

very physical spiritual traditional yoga practice that has a deep meditative and breath Focus component I know you've had lots of episodes and discussion about the breath and the importance of that for awareness um you know at the end of a of many Western Yoga practices you end with Namaste which is expressing your respect and for the connectedness of what is in front of you to the whole universe and what's common to all of us and everything and I usually practice yoga by myself and when I say namaste at the end of my yoga practice a

part of that is to myself earlier when I asked you about how you guide your decisions you said it's all feel and you provided a beautiful description as to how and why that occurs for you and your trust in that I don't recall you saying whether or not the feeling is in your head or it's a whole body feeling does it have a particular signature to it that you'd be willing to share is it excitement that makes you want to get up and move or is it a a Stillness I think I I ask because

we've been talking throughout today's episode about you know the Precision of neural coding and these signals that are at the level of individual cells and And yet when it comes to feeling we actually have a a pretty crude map and certainly a deficit in language to explain what this feeling thing is and I I know that people experience life and feelings differently but I think it's often insightful when somebody uh with your understanding of the nervous system and yourself can share a bit like what does it feel like I love that question and it relates

to something you said to me years ago uh what it feels like uh is ease and I remember years ago when we were talking about challenging things that each of us was facing in our lives you said to me something like I I wish for you some ease with all of this it was very um moving touching as that's what a good friend does is to give that to somebody to who they love and um um and it sticks with me probably 10 years later so um the feeling I feel when I'm on the path

that makes sense for me is ease it's there's just nothing it's just okay this is it I love that I don't actually recall that specific conversation because we had many many conversations sitting in your yard in San Diego on those plastic chairs with your um with my Bulldog Costello hanging out by the way folks EJ knew Costello my Bulldog Master very well and he was not a huge fan of dogs prior to meeting Costello but um Costello flipped him he he became a at least a Costello lover I love Costello I'll never forget him yeah

he embodied ease he did nothing but sleep and eat uh he he embodied um energetic efficiency and everybody loves him everybody who gets to be in the same room with him loves him the people I just spoke to in your setup here your colleagues you know yeah I could see why and you have a beautiful photo of him hanging there yeah yeah he's a what a creature a great great memory definitely embedded in my nervousness I often choke up when I think about but I I want to be clear because I've already cried once about

him on a different podcast I don't want to do that today they're not tears of sadness it's this crazy thing like I love him so much I just kind of want to explode so damn it costell got me again and publicly again so he's someplace laughing so I I love that um and I think if um if I made you know do you think it's worth kids and adults learning to recognize those those kind of States those signals that tell them they're on the right path by paying attention to I don't know this like like

we said there's sort of a deficit of language like eases in the body eases in the mind it's the release of I mean you know it's not even worth exploring verbally because it's a is such a whole body whole nervous system thing yeah I I I feel like I I actually was thinking about I was giving advice to a young fellow who uh is applying to graduate school recently and had a zoom call with him about stuff and he had received some good advice from some other people and then I gave him some advice and

I saw him and speak and emote and with body l language drop into like oh yeah that makes sense yeah that that feeling of course kind of the of course and I think if you can teach people to do that I don't know if the verbal communication of that is going to like you said is that going to do anything but can you at least observe it in them as a teacher as a mentor and do things and when you know when you've done it because you see them drop into ease do you think you

can detect ease in people by looking at them and seeing their body body language and everything it's it's got to be an amalgum of different things that the Cadence of their breathing their pupil size it's not worth dissecting this is an experiment I would not want to run yes right I wouldn't want to bring people into a laboratory and figure out you know what pupil of the eye Dynamics combined with certain rhythms of breathing relaxation of the shoulders because it's too beautiful for that is it's too beautiful and it's it's too nuanced and um it's

different when we're in Motion versus when we're lying down it's like I mean science is capable of a great many things but I don't think needs to be pointed at every aspect of Human Experience I think they um some of these things are are simply worth allowing to just be do you feel the same way about when you when you have a feeling about a person you meet somebody and their energy just captures you it's like wow what a cool person what what amazing energy do you want to know the science behind that I don't

no I don't I think the the word that comes to mind when I experience somebody like that or something like a animal or you see something the movement of something or a beautiful piece of music or something is uh the word just behold yeah I just want to stop and and take in as much of it as possible and here's something I know you've done but I'm checking to make sure I really got this right because I've done it too because we sometimes get human retinas for doing our experiments the first thing that happens when

we get the human retina we bring it back to our lab it's a big production everybody's getting ready to go a whole bunch of moving Parts going on we have to open up the eye and look into it to see what condition it's in and it's typically on with a dissecting scope on a chair and it's open sitting on a chair dissecting scope looking down look into the eye it is so beautiful it it's breathtaking each time I've looked at the retina I don't know how many times each time wow this is what's initiating all

the visual experiences I've ever had in my life or that person ever had in their life right and the beauty just keeps coming I love it and I love it because you're talking about a behold moment that isn't just to entertain your curiosity sure it's that you want to understand how the brain works um but also a behold moment that leads from that desire to understand to a deep level of understanding now after you know more than two decades of exploration to a mission in service to humanity restore Vision to the blind develop neuroprosthesis and

other types of neuroengineering technologies that will allow the human brain to function better than it would otherwise so there's real purpose there too so it uh represents kind of a perfect ecosystem of it's not just about delighting in something and and um and spending one's time there there's a real there's a real Mission there so um I love it well EJ Dr cheski uh Dr huberman I rarely get called that these days um when I invited you here today I was absolutely sure that uh our listeners and viewers were going to get a absolutely worldclass

explanation of how the nervous system works and the the retina and the visual system in particular and um that it would be delivered with the utmost Clarity which it was so thank you I know there's been so much learning in and around that and you beautifully framed for us what that means in terms of the larger understanding of how the nervous system works and what you and other Laboratories are now in a position to really do with that information and the technologies that are being built and that will be built and you know the purpose

in bringing you here today was was just that but not that alone um you know I think we hear so much about the brain and how it works and everyone wants to have tools and protocols to function better but um it's clear that the work that you're doing is headed in a Direction that's going to vastly expand the possibilities for sake of treating human disease and and for expanding Human Experience I'm I'm certain of that what I did not expect however was that when I wrote down one bullet point well actually two I wrote still

a coffee snob question mark the answer is yes um and yoga you know that we would end up in territory where you would share some of your experience that I myself was not aware of about this um a bit of a Wandering um of three different PHD programs and of this um cultivation of an intuitive sense of of beauty and taste and preference that the way you described it takes you out of your rational mind and into the aspects of your nervous system that just really act as a compass toward what is absolutely right for

you and we're all so lucky that what's absolutely right for you turns out to also be what's absolutely right and beneficial for the world so thank you for coming here today thank you for sharing your knowledge and your heart and for doing it with um such an incredible degree of of openness and respect so thank you so much thank you Andrew it's a great pleasure really appreciate it thank you for joining me for today's discussion with Dr EJ chisi to learn more about the work in the chich niski lab and to find links to EJ's

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to consider or topics you'd like me to consider for the hubman Lab podcast please put those in the comment section on YouTube I do read all the comments not during today's episode but on many previous episodes of The hubman Lab podcast we discuss supplements while supplements aren't necessary for everybody many people derive tremendous benefit from them for things like improving sleep for hormone support and for improving Focus to learn more about the supplements discussed on the hubman Lab podcast go to live momentus spelled o so it's live mous.com huberman if you're not already following me

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and last but certainly not least thank you for your interest in science [Music]