Lecture 10 Recording

Okay, um...

Let's do some quick review.

I've kind of lost track of what we've talked about because I'm juggling slides around from different lectures now and

We're on lecture, we're on lecture 10.

What?

And now until lecture 18 from

this course because of the time difference.

I apologize if I reviewed something more than you like.

machine driving fire.

Okay, so we were talking about sound localization and trying to

I want to give you some intuition and impress upon you that the auditory world is both

Uh...

frequency based and space based. So you have a map of frequencies on the basilar membrane, but you also can compute from the timing of the basilar membrane activity something about where things are actually in space. And that, of course, is going to be super helpful to use sound as a modality of information. If there's

If there's information that you have, the brain tries really hard to get it.

It doesn't usually leave information on the table, either.

So just to sort of summarize, I'm sure localization, we said that there are, there's two main cues for azimuth, that's this angle, that was ITD and ILB. We dug into ITD a fair bit, that was the Jeffress.

model of delayed lines of frequency vectors. And then we talk about reverberation. It gives a sense of distance or spatialization of sound.

It doesn't sound like it's coming from inside your head. It sounds like it's out there in the world.

And we talked about the pen-a.

the outer part of the ear and that we said that that funnels sound into the ear canal but it does so slightly differently for sounds that are at different altitudes. So this angle

especially this angle. And it does that by filtering out certain frequencies depending on the angle.

So maybe high frequencies get filtered out at this angle, but low frequencies here, and then medium frequencies here, and then it's high frequencies again here. So because of this really complex shape of your thing.

So that's useful for our elevation. Now something that I alluded to but is a little bit complex and we didn't really dig into it is that

Um.

What we're trying to do with all of this is to localize something in space. Of course, it's to make what we call an allocentric map.

Allocentric refers to a coordinate system of things in the world around you that doesn't change when you move around it.

So it's sort of fixed in place. Notice that that's very different than the egocentric representation. So these cues, initially they're egocentric, especially if you think of IT or ILD.

So if something is directly in front of you in the midline, it has ITD and IOD cues that are

telling the prey that are derived from the fact that the arrival time and headshot is the same in the two years.

If it's out there in space and I turn my head 45 degrees,

That sound image is shifted by 45 degrees in my egocentric

localization of the auditory world. But of course it's not moving in the allocentric world.

So my brain has to be able to figure that out so that it doesn't sound like that thing is also

So ultimately we're using these egocentric cues to build up an allocentric representation of the world.

I just want you to keep in mind that none of this is static. You're constantly moving through the world, you're turning your head, you're keeping it up to this.

That's a really good way to get altitude information.

because if you tip your head this way, now you can use ITD and ILD.

to get up, alpha 2, 2, right? So you're constantly moving your head around.

And the things in the world are also constantly moving.

So you're ready to keep track of all of these things, so the egocentric representation, map it to allocentric, and then keep track of things that are moving around in space. It's actually a really computationally difficult problem. It's one that we've actually worked on in my research group.

to develop hearing systems for robotics. Because of course, robots face exactly the same problems. They move around in the world, things move around in their world, and if you want them to be able to hear, they have to solve the same problems as humans.

Okay, we were talking a little bit about how the brain represents

So as we go along, we've talked about the Jeffers circuit and the Indian brains, it's a little bit different. Humans, those are that computation of ICD and ILD.

is solved by brainstem nuclei.

And then you actually see the first real map of space in mammals emerge in the superior photos and inferior photos.

So that's what this graph is showing. This is a cat.

If you're a quickness, try to screw your quickness.

Um...

And then I said, there's also sound in the cortex.

in a so-called wear pathway for audition.

that's in this temporal parietal junction and what the region called the planar temporal at the back.

Very double-jacks.

So primary alpha-recursive is here, this is sort of behind primary alpha-recortex.

and there's cells there that are tuned to space. What does that mean? It means that they'll respond to certain sounds, but only when they come from a particular location in space.

You can play exactly the same sound, but it's over there and they won't respond.

So those cells do know something about the world, but it's not like it makes a really clear map of space the way that there's a map

of visual space in primary visual cortex. Which we'll get to that, but that's probably intuitive. Because there's a map of space on your retina, there's a map of space in your

and also the archery system.

Okay, when we started talking about speech, we talked about phonemes. Phonemes are sort of like

like the acoustic building blocks of speech.

And then phonemes are nested into syllables. Syllables are usually three.

But when you stuck together up with a consonant vowel, consonant sound...

And then of course syllables make up words. Something in English anyways, like 60% of words are one syllable and the other 40% are like two or three, four syllables are super early.

And we said that phonies actually have these interesting

acoustic patterns that show up in the spectrogram.

And we have been using the language

acoustic saying that these lowest frequencies are the fundamental frequencies and that's the frequency that you associate with pitch.

And then there's harmonics. In its beach research, the harmonics are both forms.

the same idea. Remember we always have sounds that are actually complex. So the sounds are made up of a superposition of more than one frequency.

When they're not, when you have just one frequency of sound that's called a pure toner,

actually really, you can't really make it in nature. You have to synthesize it.

computer and then as soon as you play it out of a speaker even the speaker is going to impart some harmonics to it but anytime you have something like vibrating it's going to have lots of harmonics.

And we talked about some of the complexities of perceiving speech. So speech is this problem of

You know, stacking together these acoustic symbols called phonemes into syllables which are now bundled together into words and words are bundled together into phrases that have grammar and

The Americans kind of oopstrapped that, built that up. In order to do that, it has to solve a bunch of problems, one of which is what we call the segmentation problem. And that is that

The apparent distinctness of each word is illusory.

If you actually look at the sound stream itself, often, syllables are stuck together and they can even span word numbers.

They don't always, often they don't, but they can. And so your brain's ability to see

us a continuous sound as different words that start and stop and start and stop.

That requires your brain to know the language, to know the rules of the language, the grammar already that

the language prior. So you have a prior model of how the language ought to work.

And then your brain can kind of parse out the different components of the sound into the words.

that you care. And we said that that's actually a really hard thing to do if you're listening to a language that isn't your first language.

It's a language you're just starting to learn. It's very hard to...

All right, I think I covered the last lecture in a little bit. Does anyone have any questions so far?

here.

Okay, right on. Let's continue talking about speech.

We're also going to talk a little bit about speech production today.

A lot of this will overlap with some of your other neuropsych classes, especially if you've taken neuropsychology.

And the reason is because lots of what we know about the neural anatomy functional neuroanatomy of speech comes from studies about lesions.

people who have lost the ability to use language in various ways.

Okay, so let's do a quick tour of

some of the regions of the cortex that we know are critical for using language, especially in speech.

And they're probably familiar to you.

One overarching concept here is that speech is a distributed process.

There is not one region in the brain that does speech.

And a consequence of that is that something like 40% of all strokes

have some degree of aphasia, the inability to use language.

because they have a scope in lots of different places and they can all impact your ability to use language in some way or another.

So some of the reasons we're going to be talking about our ropism.

and

We're in the East area.

and we're going to be talking about the C-fields which is a white matter tract that connects

these two area, the Perky area.

and just reminding you, primarily out of three projections.

Bye.

that's reviewed too.

So let's talk about a phageo just briefly.

Did you learn about aphasia in the second year of neuroscience class?

little bit. So this should be largely review.

So a vision is a disorder of speech production or speech perception.

But there's a concept here that like,

It really does

illustrate what the cortex is for.

So...

It's not just like the encoding of speech input or the

output of speech-motor commands. It's the ability to use language.

in a more abstract way. And so the deficits that you see in aphasia are sort of

level deficits if you actually like see a person or listen to a person who's who hasn't a patient you'll notice it like

They can hear, right? They can hear, and they can make sound. There's nothing wrong with the encoding stages or the output stages. The problem is in how language gets put together in complex.

high level ways in the cortex.

uh... one of the most famous cases

case studies of an ophasia. Of course, Paul wrote this patient tan.

probably encountered something about this. And this is ultimately what led to that region of the Great Deep called Rokhuz area.

So, dot tan had a

add a lesion to the left for the cortex.

This area is kind of a supplementary mortar area.

Like, these are motor, these are motor barriers.

They're not at 1. They're not primary order cortex.

but there are areas that are involved in like coordinating and putting together

planned motor actions that integrate with the world. So high level pump up.

Tan was called tan because

and Roka's aphasia is like characteristic simple

is that

So they can't produce speech, but the speech that they can produce

is usually like one syllable sounds.

Sometimes they can get some words out but mostly it's sort of incoherent, unintelligible speech sounds.

So sometimes it's called non-fluent aphasia because the sounds that they're making just don't come together into anything that sounds like speech.

If you go on YouTube, you can see a bunch of videos that are examples of these different kinds of aphasia. It's worth watching because they're really interesting and you'll see

Clearly, people with broke-in-defage edits...

The deficit isn't in like just like the motor coordination. It's in

turning word ideas into word ideas.

output.

It's mapping the lexicon to speech production.

and you can see that when you listen to someone with pepper.

Okay, and that's actually a hand-breaker.

Absolutely.

It turns out actually, we call this area Rokas at beta, but a Rokas

Actually the Legion also goes into the Insoam, which is a Legion of Cortex.

And so it's not fair actually, Tan might have had

like the aphasia that tan had might have been due also to elitancy.

Another classic aphasia is called verticose aphasia.

And very easy pages, they're different from words of pages. They sound very different. Clinical presentation is totally different.

So vermicephesia is really strange and interesting. It's called a fluent aphasia because unlike rocas aphasia, people who have vermicephesia

can talk, but what they say doesn't make any sense. It's sometimes called word salad.

The words, they kind of sound like they're grammatically correct. They string together into sentences that if you weren't paying attention, if you just heard it happening over there, you might think that person's just fine.

But if you listen to what they're saying, it doesn't make any sense. And it's...

connected to the fact that they also can't understand.

So by contrast with Broca's,

Vermic esophageal patients have a comprehension fallacy.

So you say something to them, they don't really understand what you said. They can sometimes give a gist and they can understand individual words. Like you give them a sentence, they get the sentence kind of mixed up.

The lesion that classically gets rise to a verdant piece of theta is now altered in half.

area and that's in the back of the temporal lobe, super temporal gyrus.

Definitely go on YouTube and listen to some of these examples that are really interesting. And you can clearly see there's a stark difference between Bernicke and Beja and

Okay, there's another kind of aphasia that's important that happens

sometimes time and it's called conduction aphasia.

And I want to talk about it because this concept actually shows up again in

the neuroscience of music.

So I'm going to go back a few slides here.

So we've been talking about Rokas area, quarterback.

Verities are yet cortex, right? But remember that a cortex is like a sheet of cells.

players.

And vertices and brokas are nowhere near each other on that sheet.

So they have to be able to exchange information.

And proper successful speech perception and production requires

It's not like Bernoulli's area gets some input, passes it up to Brokism and then it's done. It's like back and forth communication to keep.

working well.

You may have experienced this.

Has anyone ever tried a speech camera?

What's a speech genre? Play something else into your ear to message the highest people. What does it play?

It plays your own voice.

delayed by like 200 yards.

So yeah, so you wear like headphones that walk out the sound of your voice.

transmitted through air, but there's a microphone that records your voice.

and then delays it for 200 milliseconds and then delays it back into your ear. So when you speak,

your voice is coming up, you're listening to your own voice.

and you're making use of what your voice is sounding like to fine tune the production part.

Right? So Broca's is using Wernicke's constantly to provide feedback about how the speech is coming out.

If you delay it, then you scramble that process. And it is the most eerie thing. Like you think that should be fine, it's just like having an echo.

Like, you just, you stop talking. Like you're trying to talk to her?

You can't talk. It's very, very, very strange to do this. If you ever get a chance, try a speech jammer. Quite cool.

So the point there is that vermices and brokers have to be in constant communication and they're sending a lot of information back and forth and they have to send it back and forth really fast.

because speech is a really fast way to send data.

between one brain to another brain. You're really pushing your brain about as hard as you can push a brain. The computational demands to generate speech on the fly in real time.

And so this system has to be really, really tightly tuned.

And as a consequence, there's a really thick white matter track that connects

So it's mild needed white matter, right? So it's got really fast connections. It's very dense because there's lots of fibers that connect these two regions.

And it's called the Arquithysiculus, that point matter track is called the Arquithysiculus.

Now, I've alluded to this a little bit here, but let's put a finer point on it.

And going back again to this picture.

It wasn't just flip of a coin that these structures are painted onto the left hemisphere.

It turns out, as you probably recall, that the left hemisphere is specialized for language in most cases.

So the Archivaciculus, as we discussed it in relation to

language, so connecting the Bernicke's and Brocie's area, is on the left side of the brain. It's in the left hemisphere.

because Bernanke's in brokos, and most people are on the left side. So connecting those two is on the left side.

This is where it matters for music. It turns out that you have an art of fasciculus on the right side, but it's critical for music perception.

But because it's so important, you can end up with an aphasia if you have a lesion anywhere along that pathway that damages the arc of the cecilulus. And you end up with something called conduction aphasia.

And there is sort of like a hybrid mixture of Broca's and Verdeke's with its own kind of

symptoms anyway.

So there's many different kinds of invasion, but those are the three classic textbooks.

kinds of a phases.

Any questions so far about these phases?

Here's a question for you. Why is the clinical picture of a phasia complicated?

Like, you know, in...

in stupid, we have a stroke in visual cortex, primary visual cortex.

or even other extra-shry approach of visual cortex.

You can get pretty clearly defined, very specific kinds of desks.

So for example, we'll learn about prosopagnosia, an inability to recognize faces.

That's a strangely specific thing. But these are phases. It's not like you ever get an aphasia that's like, you did ability to say nouns.

or play.

They need colors. That's a visual kind of.

of agnusia, not an atasia.

So the clinical picture of a phasia is really complex. There's no like textbook of phasia. The clinical presentation is always complicated. People who have burnicles of phasia, like...

They can't understand very well and they can't produce.

sentences very well because they can't make sense.

even though the words come out. But words come out when they're not the right words.

So that's kind of here that seems like it's two different things right bro goes they they understand fine

But they can't talk, they can't get the right words out and what they can produce sounds all sort of

garbled and muffled and it's not really words, right? You also can, right?

So they can't out-post language any which way. There's a block in how they can produce

language has output.

Why wouldn't that be? Why is it not given to the people?

back to what we said about strokes.

Exactly. So you can have strokes in different parts of the brain.

And remember, strokes don't really respect functional boundaries.

because the vasculature doesn't line up with the broadener.

And so so you can have like if you have

broke a stroke that damages broken area, for example.

You may also have some

like uh, impraxia, an inability to write, but because you can't control your hand.

Not just because you can't output the words you're trying to write.

Um...

the arc of fasciculus is this long white matter track.

If there's a stroke that affects it, it's probably affecting other things too.

So when you have a patient that presents with some of these, there's often this whole cluster of different things that have gone wrong.

take an improvement over time and then sometimes it can't.

on the size of the stroke and also how long between when the stroke happens and when you get like clock busting drugs.

return blood flow to that.

Okay.

Questions in the bell?

pages.

They don't even know anyone with an up-date data.

Yeah.

It's pretty common, like, a faces are common.

Among stroke patients.

But you will encounter people.

in your life who had some kind of aphasia from stroke.

Sometimes depending on what career you go to, you might work with people.

The most important thing is to remember that

These strokes haven't affected their cognitive

ability to think.

And so it's extremely frustrating, especially I think for pro-gens of phasia, but I think all of them, because

They know what they're trying to say, but they just can't make it come out.

Yeah.

That's super frustrating. Just be very patient with such patience and just go really really slowly.

Thank you.

They often have trouble with that.

They can't write, but it also comes out like word salad. That's the thing. So would this be word salad?

Yeah, yeah, that's what I was trying to get at with this idea that it's cortical, meaning that it's high level, it's abstract.

So they can't like string together coherent produced.

language output and it doesn't add to the modality. Now that's the classic textbook definition, but like I said every trope is different. And so there may very well be patients with vertices, aphasia that can understand sign language.

It would be pretty rare because you have to have some money.

already understand sign language, it would probably be very difficult to learn sign language. Go talk if you have

Um...

Yeah, so if you're interacting with patients who have phages, just go really slowly, use very simple phrases.

maybe one word at a time, draw things.

You can write them and if you write a word and say the word, that's helpful.

and you know they're very complicated stuff, just plan to take a long time and let them take a long time to say what they're trying to say because

They can get the words out eventually. Like, it'll make sense. Like, often in Bernese,

aphasia like

It'll be this like jumble of words, but one or two of the words in that sentence are

the right context. Like, like it is really like there's clues about what that person is trying to say. And if you pick up on that clue, and you say, Oh, dog, do you mean you walked your dog? And they'll say like, yeah, yeah, sunshine beach dog trees, trees walk.

or something like that. And like, okay, yeah, you're trying to tell me about it.

So you can sort of piece, work with them to piece together what they're trying to say.

It must be brutally hard.

There is like, like you can do speech therapy for these and get some degree of function back.

So it's worth spending time and

people who have these faces.

Okay, the last thing we need to talk about in...

of speech, perception, and self-production.

is some of the neuroimaging elements.

And this as a field is too big for our course to delve into. There's tons of research.

that uses functional MRI, especially functional MRI.

to study language. One of the first things that people started doing in early like, PET studies at FMRI studies.

So for example, this is a classic study by a guy in Jeffrey Binder and others.

in 2000, so that's like early days for functional MRI.

The earliest real fMRI research was coming out in the night

And he did this really interesting study that kind of confirmed what

already suspected about the functional anatomy

based on Legion status.

and it was a block design study. But it's a little more complicated than the sort of simple block design studies that we've talked about so far.

Remember in a lock-in-time study, what you're trying to do is contrast

two or more different regions of time.

you've got a person in the scanner is doing some cognitive task or

perceptual task and then there's some contrasting period of time. Sometimes it's all that rest but it doesn't have to be rest. They don't have to be actually trying to do nothing.

be something else and then they're doing the task again and then doing the rest again and so you can do a statistical comparison between any two different kinds of things you're having the person do it means different to walk

So what they did here was kind of a tricky way to bootstrap up

some understanding of the complexity of the

of the language system as distinct from just the auditory system. So remember that like

Perceiving speech is perceiving sound.

Let's leave life.

sign language aside for now. So preceding speech is sound perception, but not all sound perception is speech perception.

Lots of sounds have nothing to do with speech, but you can identify those sounds and interact with those sounds and produce those sounds even though they're not speech. The challenge here is to leverage a part

functions of the cortex that are unique to speech perception.

not just sound perception. So that's an important point. The other challenge, of course, here is that fMRI scanners are allowed.

you've got like you constantly got scanner what's going on it thinks this like eye pitch sound

And so that's kind of it.

cruise up your design a little bit because now you've always got these sounds going on.

trying to like play sounds for people but it's really hard to hear them because there's this other opinion going on

Um...

They often still use air conduction headphones.

So you can't have a speaker inside the magnet, right? Because it's a magnet. A speaker is a magnet.

So the speaker has to be like 10 meters away in a different room.

And then there's like this hose that's just full of air that goes through the wall.

table into the board of the magnets, puts a part into the ears.

And that's what you listen to. Now there's shielded higher quality things too.

We use an air conduction system, right?

So it's still kind of the best way to do it. If you put metal in a scanner,

Like the best thing you can hope for is that it just causes huge susceptibility back in the...

worse is it gets stuck to the inside of the scanner and possibly kills the

So there's all kinds of technical challenges. They're doing this kind of work.

They did find some really interesting results and these results have been replicated and expanded upon in countless studies now.

the papers now that look at various aspects of speech.

This was the first order among

Um...

Let's talk about what they did. So they had several different contrasts in the block design kind of way.

So they had sound compared to no sound.

keeping in mind that no sound means there's still the pinging of the scanner going on, but in the sound condition there's the pinging of the scanner plus some other sounds. I think they were like frequency monitoring.

And then they had previously modulated tones.

compared to noise like shhhh.

So the brain doesn't care much about that sound, but it gets pretty excited about frequency modulations because they usually have information in them.

So that's an interesting comparison. And then they start to be clever about trying to get at actually what makes speech, speech.

So one way that you can do this, to have the right kind of comparison, because remember, in this block design approach, the thing that's going to make colorful blocks

is whatever is the thing that's different between the two blocks.

And so you have to be able to design those two blocks in a way that isolates that one thing you're trying to figure out.

So if you're trying to figure out what's the difference between speech

and non-speech sounds, you have to use sounds that have very similar

acoustic characteristics but aren't speech. It doesn't work to compare someone talking to

because that comparison is going to get the difference between things that sound like speech

maybe R or R not and just this sort of uniform broadband noise.

one a day

Very since they did it was speech and reversed speech. So you take the WAV file and you just play backwards.

If you do that, you get all the same acoustics. The frequency modulation is going the opposite direction. It's happy decay is a little different.

It sounds kind of like speech. If you weren't listening carefully, if you just heard reverse speech off to the side, you could go over through.

You might pick some of the soft and uni different language if you didn't listen carefully to it.

Another contrast that I'm going to use is words.

and then pronounceable non-words, so like consonant, vowel, consonant.

syllables but they don't actually mean a word. You can say them. They might be a word in a different language but they don't mean a word in English. So this, so the speech versus reverse speech gets you the contrast that reveals what's unique to speech.

It's Seth versus...

sounds and this contrast gives you what's unique to actual words that can connect to a meaning in your mental dictionary versus

Sounds that couldn't be worked, but don't connect to anything.

And the results are sort of what you would expect. So purple areas.

primary cortex are responsive to the contrast between sounds and notes

frequency modulated tones and noise. And then you get this kind of pattern of

increasing specificity when you get further away from primary auditory cortex.

like visual, primary visual cortex, is pretty nonspecific. It doesn't really care about the details. If there's sound coming in, it's going to respond to it. It doesn't differentiate between speech and from talk.

But then there's other parts of the temporal lobe, frontal cortex.

that differentiate between

words and non-words or speech and speech-like sounds that aren't that

One conclusion that these authors seem to is that there is no one language center.

for some other things, some other cognitive mechanisms.

So you have a distributed system of cortex that does

But they definitely did confirm this atmosphere

in most people.

languages lateralized to the right side. Notice I'm saying most. It turns out some people, languages lateralized to the right side.

And some people are bilateral for language.

If you're left-handed, you're more likely to be right-lateralized for language.

but you're more likely to be right lateralized than if you're right handed.

But you're still more likely to be left higher. Does that make sense?

very few people who are right handed are right lateralized for

This kind of spirit laterality is a classic.

It presumes a lot of it in the spirit.

It's interesting

Perceptual behavioral consequence which is called right ear events

Have you ever heard of break-ear advantage before?

Okay, so if you give people like a lexical decision task, so a lexical decision task is like this, I play words and also sounds that are like pronounceable but they're not

words in English, right?

And your task is to say whether or not it's a word. So you just say like, yes, it's a word. No, it's not a word.

You can, so that's less of a decision, you can time a lot of these people to do that task. How, what's the response time?

say yes or no. It turns out that you'll be faster if you play those words into your right ear than your left ear.

think about why. Remember the sensory systems are largely mapped contralight

especially in vision, so the left visual field back to the right.

It's not quite so pronounced in hearing, but it is the case that something like 60% of auditory pathway fibers

go to the other hemisphere. So you've got a stronger connection crossing. So if you get input to your right ear, it goes to your left hemisphere first.

And then your weight hemisphere.

I'm gonna go get my bag.

way around

But if it's worth doing the selection of the syntax, you need your left handster to do it. So you get this sort of like shortcut, close to your right ear, close to your left ear, just two hands through the left ear.

Interestingly, there's a left-air advantage for music.

Okay, any questions about...

to the sort of neuroimaging story about

Yeah.

Yeah, yeah, so strongly write lateral eyes for like

Yeah.

turns up from time to time because

Like people who have intractable seizures, if they happen to be generated in a temporal

And they're not.

to the drugs.

Sometimes the part of the brain that we call it F to the left of J, the part that generates the seizure

He did it as we do this.

it's probably not doing anything because

and

Cheers.

Um...

You do not want to do that though.

if that part of the brain is at the top of the temporal lobe.

and it's the temporal lobe that is dominant because, yeah, seizure will stop it, you'll have an ovation.

And so people try to figure out, like, neurosurgeons do, what's helpful.

pre-circled brain mapping to try to figure out which side is Bernicke zone.

so that you know when you take out, like if it's on the...

the right side, don't take outright hemisphere.

Used to be...

This was done with something called a WADA test.

It's not really done anywhere. It's almost always done with fMRI now, but it used to be that it would inject anesthesia, general anesthesia, into one or the other carotid, anesthetize one half of the brain and see if you can still talk, means that anesthetize the side that isn't dominant for language in the brain.

you get excited.

Is there a benefit to using fMRI?

inter-criminal.

Oh yeah, so people will do that too, eco-g.

electrodes on a sub-derral grid. Yeah, you can do that, but

You have to cut the skull open.

So you have to do it all in one surgery.

Whereas if you can do FMR, you don't have to cut anything.

So ideally...

I think what's commonly done is they'll do pre-circular brain mapping with epimerite and confirm we've all done it.

in there.

I don't know. Pending this is...

Terrible.

But I don't think it's well understood why we're even handed.

And not just why we have pen in this, or language-wide or something.

But why is it so symmetric?

like other primates into the catatonic.

but whether it's left handed or right handed is even being distributed.

just as many left-handed, chimpanzee-deterred.

Yeah, I'm not sure why. It's a... yeah.

very

Find the language letter as they can. Does anyone take E. neuropsychology right now?

with Kevin Kast?

So you'll cover this. If you haven't already, you'll be all right.

They didn't want to take it with pride.

It would have cost me $10,000.

Any other questions?

I've seen a water test done.

So you may have heard that the different hemispheres

have different characteristics.

other than the negative aspect.

So I always forget which one is which, but what I have a spirit tends to have positive affect and like happier thoughts.

and what I'm scared to have for a negative thought.

So I got to see a lot of tests done. This kid, he's like 15 years old, had intractable epilepsy and they're going to reset part of the temporal lobe and they're doing a lot of tests to make sure that they know which side is going for language.

Turned out, given the bilateral and denominator language.

Bye.

And as they were doing it, they're explaining the gap. And you're going to see the difference in the path.

day at SSI's one hemisphere and he was like hitting on the nurses and stacking jokes and laughing about stuff and then you wash it out for like an hour and then and then I studied the other time and it's like

and crying and fearful and totally a different person.

by just shutting down one or the other hemisphere. Really, really striking to see.

So doing a Y test doesn't just tell you lateral, lateral, you can tell

Okay, any other questions?

It's a long weekend, so we're all gonna stop there.