[Music] hey welcome thank you so much for clicking on this video but why did you click on this video not even 10 seconds ago you were mindlessly scrolling through your YouTube feed and then you saw this title in thumbnail and something in your brain had to know what it was about so you clicked but what was that something in your brain seriously tell me I might get my click rates up but for real though we've got a motor cortex a visual cortex and AIO cortex but where did decisions come from that question got a lot
more complicated in the 1960s when a new surgery started being performed on people with extreme epilepsy it was called a corpus callosotomy or split brain surgery yeah try to guess what they do yeah they split the brain in half of course the brain is already pretty much split in half between the left and right hemispheres but they're connected at the bottom by a bundle of fibers called the Corpus kosum so yeah they just kind of cut those fibers this made it so the two halves of the brain couldn't communicate with each other which sounds like
it would be a huge problem um but believe it or not they went on to live normal lives this surgery didn't change people's personalities or ability to function but there were some kind of weird things that came out of it you know things like their left hand would start drawing something and they didn't know why it's like there was something in their right hemisphere that was trying to communicate there were kind of like two different people in there so if that's the case the question becomes which one of those two entities are you know running
things the subject of split brain experiments has come up from time to time on this channel but I don't think I've ever really done a full video on it so I decided to do one because this topic is one of those things that just really caused this shift in like how I see the world how I see other people um how I see myself and it came from a book that I'll be sourcing quite a bit in this video and I highly suggest you read it uh it's called who's in charge by the neuroscientist Dr
Michael Gaga taking tropus notes as you can see he did pioneering work on split brain patients in the 60s and 70s he's written several books about it done TED Talks I'll link it all below but the reason this book speaks to me if I may I don't know get a little personal for a second I I've kind of always had this theory that there's different gnomes in my head obviously I don't think that actual garden gnomes are living inside my skull that's crazy but like most people I imagine I do have kind of kind of
different voices in my head that have thoughts that Bubble Up from time to time some of which I don't even agree with I call it a defense mechanism call it a rationalization of bad ideas or whatever but that was kind of my way of explaining why I sometimes had conflicting ideas or had troubl making a decision um or like the negative thoughts that kind of take over sometimes that's that's the negative gnome taking the wheel not much unlike the world they created in the movie Inside Out which I just saw for the first time uh
fairly recently and I've got to say like the way that they structure that world inside of her head to explain how memories work and emotions work um I thought it was brilliant something else I liked about the movie was that the stakes were so small but it still felt like a big thing like the the climax of this movie is a little girl telling her parents that she's sad and it carried more emotional weight than all these movies were like the world ending is at stake you know anyway the point is that this book and
the split brain experiments that he talks about in this book seemed to make the argument that my little gnomes explanation for how my thoughts work isn't too far off the mark and that Free Will and Consciousness is Just an Illusion there's a lot to unpack here so maybe we could start by asking the obvious question which is why were they cutting people's brains in half again yeah it's a procedure called a corpus colotomy and they started doing it first back in the 1940s as kind of a last resort treatment for severe epilepsy here's how it
works when you have a seizure what happens is that there's a surge of electrical signal that disrupts the normal firing of neurons across the brain depending on where this occurs in the brain you'll experience different symptoms for example an ocular seizure might give you a a flash of light but the worst of course are the ones that spread over the entire brain these can lead to Temporary paralysis and convulsions vomiting basically everything you think of when you hear the word seizure and in people who get these multiple times a day to the point that they
can't even function normally and no treatments seem to stop it well the best option is to just contain it so the Corpus callosotomy is done to prevent the signals from spreading to the entire brain so it stays in whatever h Spirit started in kind like a surge protector the First Corpus callosotomy was done in 1936 by a neurosurgeon named Walter Dandy uh kind of on accident he was removing a tumor on a patient's pineal gland and it required him to cut through the Corpus kosum to get to it he reported that this had no real
effect on his patient which there had been a debate for a long time about what the Corpus kosum was actually for like was it actually involved in processing or was it just structural just kind of there to hold the brain together um the result of this experim expent seem to suggest the latter regardless in 1940 William P van wagen and decided to try a corpus colotomy on an epilepsy patient and he saw mixed results at first but they were promising enough to continue experimenting with it by the way this is all starting to sound kind
of familiar all of this happened about the same time as the labotomy which I I covered fairly recently this was basically the period of Neuroscience when they started paying attention to the white matter fibers and cutting connections just to see what would happen I should be clear though while the btoes were being handed out like candies split brain surgeries were much more extreme and pretty controversial at the time actually this was only for people with a very specific very debilitating condition and even then it was only a last resort it really wasn't until the 60s
when two neuroscientists named Joseph Bogen and Philip vogle kind of perfected the procedure and it became thought of as an effective safe treatment but not without a few weird side effects like sometimes they had trouble getting their two hands to work together um one patient talked about how he had trouble buttoning his shirt because he'd be buttoning it up with one hand and then his other hand would would go up behind it and unbutton everything that he had just buttoned and stories like this just kept coming up like patients whose hands would just grab things
for no reason or or would mess with the other hand um to the point that Joseph Bogan decided probably somebody should research this luckily he knew just the perfect person to do this a neuropsychologist named Roger Sperry Roger sper was born and raised in Hartford Connecticut and went to overlin college on a scholarship where he originally wanted to major in English uh but he took an intro to psychology class that sparked an interest in Psychology yeah The Story Goes that apparently his Professor was disabled so Roger sper kind of helped him to to get around
and took him to various places and stuff so he wound up kind of sitting in on conversations that this professor was having with his colleagues uh talking about their research debating different psychological theories and whatnot and he just got sucked into it he just found it fascinating so he got his master's degree in Psychology and later a PhD from the University of Chicago and then he went into his career he became more interested in neuronal specificity in brain circuitry basically like how different parts of the brain work and how they're connected did experiments on rats
and salamanders and involved kind of rewiring their nerves like in their legs and their eyes to see if they could adjust um spoiler alert they couldn't but through all of his research he kind of became known as an expert and how different parts of the brain uh work and how they talk to each other so of course Bogan thought that he would be just the right guy to study split brain patience and of course sper took him up on it because what an amazing opportunity he did also do some experiments on animals before he went
into his human research I know none of us like to hear about animal experiments but he did do some Corpus colos odies on some cats and tested them luckily he didn't have to do the surgery on the split brain patients CU well that had already been done so SP found a group of Bogan patients that were willing to volunteer for his tests which focus on Vision language and motor skills this would involve showing words or images to the left or right visual fields to see how the different hemispheres handled it this requires some explanation as
you may already know the hemispheres are what they call contralateral meaning the left hemisphere controls the right side of the body and the right hemisphere the left side of the body um also known by its technical term crisscross applesauce but your eyes are a little bit weirder it's not quite as simple as just each eye goes to the opposite hemisphere they they go to both hemispheres at the same time what happens is the two optic nerves converge at a spot known as the optic Chasm and there they split apart with one split carrying the left
visual field and the other one carrying the right visual field and then the left visual field from both eyes gets sent to the right Hemisphere and the right visual field from both eyes gets sent to the left hemisphere so it's still controlateral but with extra steps so if you're staring at my face right now Zoe is in your right visual field you're seeing her blessing you with both eyes but it's the left side of the brain that's processing that image your right hemisphere literally can't see Zoe right now but it knows she's there because the
left side sharing that information through the Corpus kosum but what if you don't have a Corpus kosum this is what Roger sper wanted to figure out so he came up with a series of tests along with his graduate student Michael Gaga the guy who wrote this book sorry I just have to clarify one one more thing before I get into the results of that test um a lot of the basic functioning of the body takes place in What's called the subcortical region this is an area that's actually shared by both hemispheres of the brain this
includes structures like the thalamus the hippocampus the amydala and a lot of other things that you probably never heard of but these kind of handle the basic stuff like motor control sensory processing um something they call proprioceptive sense which is basically our sense of our body's position in space so that's handled before everything gets split up there's no one hemisphere that controls that this also includes what Dr Gaga calls an integrated spatial attention system which is basically something that directs where the brain pays attention to things so uh it's not like you could be doing
homework with one side of your brain and gaming with the other side of the brain that'd be nice though anyway I know that was a lot of exposition but it's just all stuff you kind of need to know before we get into the good stuff so here comes the good stuff so one of the first patients that they studied was a man named WJ um they kept their names Anonymous for obvious reasons wj's test started out pretty simple they showed him pict and words in a right visual field and then he was able to respond
with his left hemisphere a dog a car a spoon easy easy because The Language Center is on the left side of your brain but when they showed an image in his left visual field that went to his right side of the brain he claimed that there was nothing there now this was a really big moment because up to this point there was still a bit of a debate around how much the Corpus kosum controlled the flow of information between the two hemispheres and this seemed to be indisputable proof because it wasn't that the right hemisphere
spere couldn't see the object they could see it just fine it's that The Language Center of the brain is in the left hemisphere so it literally didn't have the words to describe it so based off of this they tried a new experiment uh this time with a basic flashing light so what they did was they put his hands under a barrier so his eyes couldn't see his hands and he gave each hand a button and he told him whenever he saw a flash of light to click the button and then confirm it verbally by saying
light so they signaled his left hemisphere he clicked the button he said light then they signaled his right hemisphere he clicked the button and then said hey why did I click that button he didn't see the light but the right hemisphere did and it was able to communicate that it did it just couldn't do it with language it's kind of like the left hemisphere has a voice and the right doesn't but now they were figuring out how to talk to the right Hemisphere and now things get a lot more interesting these kind of results bore
themselves out over and over and over again with other split brain patients as well like in one experiment the left hand was placed in a box a handful of objects in it and then they flash an image of the object in the right Hemisphere and the left hand was able to feel around and and pick out the right object when they asked the patient why he grabbed that object of course he had no idea and sometimes a patient could just draw the image for example they flashed an image of a bike at the right hemisphere
of one patient and then his left hand drew a bike but think about the experience that the patient is having he's he's just sitting there he's got a pencil in his left hand and he's waiting for them to flash an image at him and he's waiting and then his left hand just draws a bike these experiments would progress and become more complex over time and they begin to understand just how different their left and right brains really are you know how we always talk about left brain people being analytical and right brain people being more
creative that whole thing well here's how the two hemispheres are actually different basically the right hemisphere was better with Visual and spatial skills and the left hemisphere was good with language like you described an experiment where the patient was flashed a picture of a a pattern of colored blocks and then he had to recreate it and when they flashed the right hemisphere the left hand was able to recreate it really easily so the right hemisphere was really good at that but when they did that with the left brain the right hand just it really struggled
with it in fact there's one story of a patient who was struggling to put it together with his right hand and his left hand kept trying to help he had to actually sit on his left hand to keep it from trying to help the right hand out to solve the problem according to Dr gag a quote the right hemisphere turned out to be specialized for such tasks as recognizing upright faces focusing attention and making perceptual distin the left hemisphere was the intellectual it specialized in language speech and intelligent Behavior there were also differences in logic
and problem solving between the hemispheres like they show the right hemisphere a picture of water and the guy would point to a picture of water then they show the picture of a pan and the guy would point to a picture of a pan but when they asked what they could do with those two items the right hemisphere just couldn't quite figure that out whereas the left hemisphere knew right away that you put the water on the pan the right hemisphere also struggled to come up with inferences like in another experiment they showed a picture of
a match and then a picture of a wood pile and they couldn't quite figure out that the next image in that series should be a burning wood pile and in another experiment the patient was shown the letter U and asked to turn it into a square using a choice of shapes and the right brain couldn't do it but the left brain had no problem like the r brain is very literal things just are what they are um he uses the example of a box of candy so like if somebody gave you a box of candy
your right brain would just be like yes that is a box of candy but your left brain will try to figure out out why they gave you a box of candy what this means is that both halves of the brain are experiencing Consciousness but very different kinds of Consciousness as Dr Gaga puts it quote it was becoming apparent that the right hemisphere had its own Rich mental life quite different from that of the left so right away we can see that there's not just one Consciousness going on inside our minds there's two but it actually
gets crazier turns out um it's actually multiple modules inside each of the hemispheres that can display a kind of Consciousness and they have their own things to say so remember earlier when I was talking about um you know trying to imagine what it must be like for these split brain patients when their left hand just kind of randomly does something beyond their control how weird that must be well U Spar and gag uh were wondering the same thing so they began developing tests to see how patients explain these actions like the left brain normally has
a gigabit internet connection with the right they're sharing everything but now it can only get information from seeing what the brain does exter internally from the from the pictures that it points to and the words that it writes and whatnot and if the left brain is more interpretive in wired defined patterns what would it interpret from that turns out a lot so in one experiment a patient was shown a chicken claw to his left hemisphere in a snow scene to his right he was then asked to choose a picture that related to what he was
shown so his right hand pointed to a picture of a chicken which obviously makes sense because the guy saw a chicken foot but then his left hand pointed to a shovel which makes sense because his original picture was a snow scene but he didn't consciously see the snow scene so when they asked him why he selected that shovel he said quote Oh that's simple the chicken claw goes with the chicken and you need a shovel to clean out the chicken shed the left hemisphere without hesitation came up with a justification for what the right hemisphere
chose it didn't say I don't know which would have been the correct answer it didn't say well maybe it's this I'm just guessing no it it confidently declared chicken poop and this was a result that repeated itself over and over and over again in another example the word music was FL to the left brain and a photo of a bell was flashed at the right brain he was then given several images to choose from these images were all musical instruments by the way uh including the Bell so the patient acknowledged that he'd read the word
music with his speaking left brain and then his left hand controlled by his right brain picked the Bell image when asked why he picked the Bell over all the other musical instruments the patient said quote well the last time I heard any music was the bells banging outside here there was a church across the street again the left brain having absolutely no idea that the right brain had seen a B confidently came up with the justification one more example of this was an experiment where they flashed the word red to his left hemisphere and the
image of a banana to his right hemisphere he was then asked to draw a picture with his left hand out of an assortment of different colored pencils so he picked the red pencil and he drew a banana but when they asked him why he drew a banana he said quote it was the easiest to draw with his hand because this hand can pull down easier which by the way makes absolutely no sense but that's what The Interpreter came up with and this was the name that they gave it by the way they call it the
interpreter module they also found the inter modu hard at work explaining emotional triggers so for example in one experiment they showed the right hemisphere a scene from a fire safety video where a guy gets pushed into a fire and the patient just reported that she only saw a white flash but then afterwards she noticed a change in her mood she said quote I don't really know why but I'm kind of scared I feel jumpy I think maybe I don't like this room or maybe it's you you're getting me nervous in another experiment with a female
patient they uh flashed the picture of a pinup girl to her right Hemisphere and then without knowing why she kind of snickered little and when they asked her why she was laughing she said that they had a funny machine like have you ever had a a random mood change like suddenly you just get angry or sad and you don't know why there's stuff going on in there and in case you haven't noticed in every single one of these examples The Interpreter module was wrong often confidently wrong it got limited amount of information and assumed it
knew everything about it might as well call it the dun and Krueger module and yet this module is kind of running the brain or at least navigating our thoughts it's further testing revealed that The Interpreter module is just one of multiple modules in the brain all of them kind of black boxes like we don't really know how they make their choices but they make choices and then The Interpreter module justifies it like for example fmri tests showed that different areas of the brain would light up before a conscious decision was made to say take an
action or to say something that was a decision being made before the decision was made this is basically how we live our lives just walking around justifying the decisions and thoughts that pop into our heads from various random semiconscious modules in our skull this fact has been such a revelation for me because I don't really think of my thoughts and my actions as me doing it anymore you know I I mean yes it's me I'll get to the theory of mind around it in just a second but it's a lot easier to look at your
thoughts and beliefs objectively if you if you don't think of it as being part of you like when I have a thought that comes up I don't know where it came from so I can just ignore it if I don't like it uh you know it's not tied into my sense of self my ideas aren't my identity and it's a lot easier to change your mind on something if you don't have it tied to your identity also once I understood that our brains are just constantly justifying things just justification machines basically I find myself often
just kind of pausing and asking myself like what am I justifying right now usually when I'm procrastinating on work like here's a crazy thing that we do have you ever noticed like that you felt anger or annoyance at someone after you've hurt them in some way um I mean like like we we've all done it we hurt people's feelings we failed to live up to a promise betrayed someone it happens that's life but there's a psychological phenomenon that happens where like we know we hurt someone and we feel bad about it but then that justification
module kicks in and just sees that you know you feel bad and it has something to do with that guy well that guy must have done something wrong and then you end up feeling resentment toward the person that you hurt which is crazy but we all do it we are constantly justifying bad behavior and bad habit and the service of comfort or protection or just a dopamine hit that's normal it makes us human but the awareness of it can kind of change your life but the other mind-blowing part of it gets into questions of free
will like what is actually controlling our decisions there are some that make the argument that this disproves free will that our decisions are made by patterns of neurons firing in a predetermined manner that we're not even consciously aware of our decisions at all these guys call themselves deter mins taken to an extreme one might make the argument that nobody can be held accountable for their actions at all because they weren't the ones that made the decision to take that action yeah seriously try that in a court to law it doesn't work and this obviously can
also be used by people who justify bad behavior because well I'm not the one who chose to do it obviously this is a bit of a a philosophical slippery slope like you know how do you have Justice and accountability in the world if there's no free will but also how can you have free will when your decisions aren't your own to find an answer to this we we have to go a little bit deeper into the nature of Consciousness itself it's time to talk about emergence theory in Dr Gaga's book he talks about the quantum
world and how it operates on vastly different rules from the macro World we've talked about it here on this channel a million times but these atoms and subatomic particles that just don't play at all in the Newtonian or even einsteinian rules that we experience um they mostly exist in probability States actually they managed to come together and combined to make physical matter the a you're breathing the chair you're on the the building around you even yourself this is emergence Theory the idea that objects in one system can combine to create something entirely different in another
system and gagaa talks about two forms of emergence strong and weak emergence he explains quote there are two schools of thought on emergence in Weak emergence the two properties arise as a result of interactions at an elemental level and the emergent property is reducible to its individual components that is you can figure out the steps from one level to the next which would be the deterministic view whereas in strong emergence the new property is irreducible it's more than the sum of its parts and because of the amplification of random events the laws cannot be predicted
by an underlying fundamental Theory or form an understanding of the laws of another level of organization an example that's always used of emergence is how like millions of individual ants with very basic programming can come together and and build giant ant colonies that are basically superorganisms with organization and structures that would be impossible for any one ant to conceptualize one could draw the same conclusion about people like forming cities or people forming the internet but our brains work the same way actually we have a few different levels of emergence we have the atoms combining together
to make the organic molecules that comprise of neurons you have the neurons firing in patterns that create this you know subconscious module that's going on in your head and then you have the multiple modules coordinating to create our lived experience of Consciousness actually it's kind of funny I've talked about octopuses in the past on here and how they have this seemingly alien form of intelligence where they essentially have nine brains because each arm has a little mini brain controlling it with an executive brain that sort of manages all of it uh it's like a hierarchical
brain system that I've always thought was fascinating cuz like it's hard for us to even conceptualize that but it turns out in a lot of ways our brains work pretty much the same way we have multiple semiconscious modules that coordinate at times and jockey for position at times with an executive justifier module that takes in all their signals and tries to make sense of it and again determinists would look at this and say that it's all pre-wiring we have no conscious control over it we are basically that guy from Men In Black with the Christopher
walking looking alien in its head drink the coffee so yeah our feeling of free choice and agency over our actions is a bit of an illusion except hold on that doesn't make sense does it if our thoughts and actions are hardwired and controlled by some wizard behind the curtain then how do we explain neuroplasticity how do we learn new skills how do we get better with practice the fact is according to the book anyway Consciousness is a result of both bottom up and top down causation we are simultaneously making decisions on a subconscious level but
also shaping those decisions at a conscious level it is possible it's not easy but it's possible to change a pattern of negative thinking by being aware of it and replacing negative thoughts with positive thoughts we do have to various degrees conscious control over our emotions and thoughts in Dr Gaga's words quote action is made up of complimentary components arising from within and from without that is how the machine the brain Works thus the idea of downward causation may be confusing our understanding what is going on is the match between our everpresent multiple mental States and
the impinging contextual forces within which it functions our interpreter then claims we freely made a choice I guess to put the question of whether we have upward or downward causation in simpler terms maybe both is happening at the same time so do we have free will yes and no a lot of our decisions it seems are hardwired and out of our control but ultimately we do have conscious control over our actions we do have agency this isn't a get out of jail free card sadly if you want to commit a crime and get away with
it you're going to have to do it the oldfashioned way be rich anyway there's a lot more in this book that I couldn't F this video it goes on into how our brains work um socially how we have mirror neurons that cause us to mimic other people subconsciously it's a fascinating book and definitely worth to read I'll put a link down in the description but again for me there's there's actually something kind of freeing about the idea that there's a lot going on up there that I don't have control of um I don't have to
beat myself up for my thoughts I'm able to give myself a little Grace when I mess up um it's just a much better head space for me yeah ironically the idea that I'm not totally in control is is kind of freeing it it it gives me objectivity and it makes me a lot less reactive I I truly believe that my life has been made better by having this understanding and that's why I talk about it so much that's why I made this video because I genuinely think it can help you too and even at a
societal level like if everybody had this understanding I think we would be a lot better to ourselves and we'd be a lot better to each other something else I can honestly say has made my life better is developing new personal hygiene habits specifically when I stopped using cartridge razors and started shaving with this bad boy the Hinson Razer so here's the deal if you were born after 1970 chances are you never actually used this kind of Razor you probably used one of these cartridge razors and that's because right around that time shaven companies um started
scamming us that's right I said scam they realized that the real money is in the blades so if they sold you a handle for next to nothing they could jack up the prices of the Blades by claiming their special magical devices that can shave your face better than the other guys blades so they started adding more and more gimmicks to the cartridges it started with two and then three blades I think we're up to five or six blades now with a lubricating strip and a bristle brush and Bluetooth connection and GPS navigation I'm exaggerating but
you you get the point they keep hyping up these new Innovations which are really just reasons to raise the price even further cartrid blades are like $2 to4 now and the best part is they don't even work very well cuz the blades are just kind of loose and flexible which means they' kind of Bounce and Skip across the surface of your skin producing what professionals call chatter but what you and I might call this leads to skin irritation and razor burn which we've all just kind of learned to accept at this point here's how Henson
fixes that they use a basic two-sided blades that only cost 10 cents each but they support them all the way across at a depth of just 27 microns that's point 0016 in thinner than a human hair this constant support all the way across the blade prevents it from skipping and bouncing on your skin and the perfect 30° angle gives it the optimum contact with the skin to get the closest shave yeah the Precision of the engineering on this thing is kind of absurd they're actually made in a machine shop that produces Aerospace parts so they're
designed to be insanely accurate seriously the guys who make this razor have machine parts for the Mars perseverance Rover they made stuff that's on Mars right now the best part is the blades are cheap they're totally recyclable so you won't be dumping a bunch of plastic waste in your landfill even the razor itself is aluminum so if for some reason you decide you don't want it anymore even that can be recycled cost-wise they flip the entire razor model on its head so instead of making a cheap basic handle and then charging out the Wazoo for
you know the rest of your life you pay a little front for the razor and then the blades are super cheap after that literally 10 cents each you make back the money you spend on the handle in like 6 months and after that you're literally saving money forever in fact if you go to hints and shaving decom and throw 100 pack of blades on your order then into the code shaving with Joe at checkout you'll get those blades for free 100 blades totally free and you can get like five to seven shaves out of each
blade so yeah just do the math on how long those blades will last you seriously I've been using Hinson for a couple of years now and I'm maybe a quarter of the way through the box that's in my bathroom right now um you literally won't pay another dime on shaving for a couple of years after buying H and razor it's just it's just a much smarter Choice So speaking to whatever brain module is making your decisions go check out Henson shaving at Henson shaving docomo shaving with Joe for the free blades Henson has been an
amazing sponsor and they make an amazing product so thanks to Henson and thanks to you guys for checking them out all right that's it for today hope you guys enjoyed it thanks so much for watching if this is your first time here um maybe check out this video it'll be on another psychological topic cuz you clicked on this video for a reason brain stuff uh also if you look on the sidebar if you're on your browser there's probably some other thumbnails down there that have my face on them go check them out and if you
enjoy them I do invite you to subscribe I come back with videos every Monday and that's it for today thank you guys so much for watching you go out there now have an eye opening rest of the week stay safe and I'll see you next Monday love you guys take care
