Lisa Feldman Barrett

THE ROLE OF EMOTIONS IN HEALTH
Video Captions (small grammatical edits added KH)
(which might also appear in separate tabs of this section for ease of study)
from  YouTube snippets: <https://www.youtube.com/@lisafeldmanbarrett7059/videos>

Intro – Nov 16, 2020
Variation is the Norm

HI everybody greetings to you
wherever you are in the world watching
this.  I am coming to you from Boston
Massachusetts.
I’m very very grateful for the opportunity to talk to you today.
I particularly want to thank Dr. Heidi Larson and Clarissa Simis
and everyone at the Vaccine Confidence project
at the London School of Hygiene and Tropical Medicine.
I’m very very honored to be speaking to this group of
scientists and scholars and responders and caregivers today, and I’m really happy to be speaking with a bunch of fellow Canadians.
It’s been a really good week for vaccines in relation to covid19 we saw that
Pfizer released news that their vaccine is over 90 effective
in the latest trials.
So today, what I want to do is talk to you a little bit about the rule
of emotions, both actually in terms of who is likely to get
infected upon exposure to a virus and also potentially who is most likely to
benefit from the vaccines when they are available.

I only have, you know, 10 minutes, so I’m going to really take this at a pretty quick
clip and I’m going to just try to hit some high notes and then give you some
resources that you can follow up on if you’re interested at the end of the talk.

So the first question really that I want to address and maybe the question
for the entire talk is about who develops respiratory illness upon exposure to a virus –
everybody, most people, only some people.

Well, it turns out we know something a bit about this a bit because
there was a set of studies performed between 1986 and 2011
led by psychologist Sheldon Cohen.
This was called the Common Cold Project and it was a series of prospective viral
challenge studies that were conducted out in the world.
Dr. Cohen and his colleagues placed viruses into the noses of healthy people,
including a coronavirus that is linked to the common cold,
and he and his colleagues observed those who developed respiratory infections
upon exposure.
In five studies between 20 and 40 percent of the people who were exposed
developed illness which means at least 60 percent of people who were
exposed to the virus did not develop respiratory symptoms and this indicates
that a virus is not a sufficient cause of illness and chronic stress.
Emotion, social isolation, social and economic disadvantage, childhood adversity
and other psychosocial factors seemed to confer risk. Social integration,
social support, positive emotions, and high-quality relationships with parents
and childhood seemed to confer resilience.
you know it’s tempting to assume that a virus is a major cause
of respiratory illness, that a virus works kind of like a mechanistic system
infecting the body in this very, very mechanistic way, and that any psychosocial factors are
subsidiary and merely moderate the virus’s impact.
After all you know you can’t develop a respiratory illness without a virus.

But a virus is not the cause, because as we saw, only between 20 and 40
percent of people across these studies developed respiratory illness,
respiratory infection upon exposure.
So respiratory infections, like most biological phenomena, most likely emerge from a complex web
of weak interdependent causal factors.  That is, it’s a complex system that your…
The virus and the body, and the brain are complex systems.
A virus doesn’t merely replicate itself from its genes in a passive human body
It has the capacity to cause infection only when the body’s cells and immune
system, and brain are in certain conditions.
So basically, the biological state of the host is also a necessary condition for
illness.  The ensemble of brain plus body provides a necessary environment for a
virus to develop and cause an infection. The human brain plus the state of the human
body contributes basically to the likelihood of its own infection,
in part by the mental phenomena that it creates, which in turn are linked to
immune and metabolic function.

So in a very real way, the probability and severity of infection at any given moment,
as well as the resilience that is exposure to a virus but with no symptoms,
is actually a unique confluence of a virus in a body with thinking, feeling, and perceiving
brain.
So both virus and the brain plus body work together in a sense as a complex
system neither one is a sufficient cause. Neither one should be ignored in science
or in practice.  And so, in this view, psychological factors, including emotions,
may be actually thought of as necessary causes of respiratory illness.
They’re not sufficient to develop respiratory illness, but then neither is a virus.

To understand a little bit about how this works, we have to take your brain’s
perspective.
So for your whole life, your brain is entombed in a dark silent box
called your skull. It learns what is going on around in the world only indirectly via
scraps of information from the sensory channels of your body
like sights and sounds and smells and so on.
These sensory changes are the outcomes of things that are happening in the
world. They are the effects of things happening in the world.  Your
brain has to figure out what caused these sensory inputs so that it knows how to
act to keep you alive and well. But there’s a tricky bit.  The sensory
information can be noisy, ambiguous, and incomplete, and any given sensory input, like
say a flash of light or a very loud bang can have many different causes.  So
consider a loud bang that could be someone dropping something
on the floor, it could be someone slamming a door it could be one car
hitting another car in front of your house.  It could even be a gunshot if you live
in the United States.
And in much the same way, your brain also has to make sense
of sensory changes that are coming from your body.  So for example, an ache in your gut could
be hunger, it could be anxiety, could be gut feeling that a defendant
can’t be trusted if you happen to be in a courtroom.  Similarly, an ache in your
chest, a pull, and a tightening in your chest could be anxiety.
It could be that you know having difficulty breathing because of
running up the stairs or having exercised, or in coming close to your ventilatory
load or because you’re starting to develop
respiratory symptoms or even the beginnings of a heart attack.

So your brain has to determine the causes of sensations when
all it has access to are the outcomes or the effects.  This is what scientists and philosophers
call a reverse inference problem. How does your brain solve this reverse
inference problem?  Well it has one more source of information.  Your past
experiences. Your brain is basically constantly remembering past experiences that are
similar in some way to the present to what is going on around you right now
and in your body.  So, what is similar to the present conditions.
So your brain figuratively speaking is not asking what are these sensations.  It’s
asking what are these similar to now. In psychology a group of things which are similar
are called a category.  So in a sense what your brain is doing is it’s using past experiences to
dynamically create categories on the fly. It’s bringing past experience to bear as knowledge to
reinstate patterns that are similar to the present.  So the brain is remembering.

It’s not a conscious experience of remembering. Basically your brain is
reinstating these powders from your past often in novel ways, which we call
generativity, to create representations that are similar to the present
conditions as a way of guessing at the causes of sensations in order
to make a plan to do something about them.

So what you would do when you have an ache in your gut,
whether you would eat, whether you would ask for help,
whether you would find somebody guilty – all depend on how your brain makes sense
of those sensations. Similarly what you do when you have an ache in your chest
depends on how your brain is making sense of your sensations.
So you could say that each category that your brain makes in each moment
is actually a population of possibilities, a population of
opportunities, a population of guesses about what to do next based on the current situation.

in this way emotions are not… emotions are made. Emotions are built as you need them.
They’re not built into your brains. They’re not reactions to the world.
They’re your brain’s constructions of the world.  Or rather a better way to
say it is they’re your brain’s understanding of what is going on
inside your own body in relation to what is happening in the world, categorizing, creating
categories to make sense of what is going on inside your own body, like an ache
in relation to what is happening in the world so your brain can figure out what
to do next to keep you alive and well.
And in a very real way variation is the norm because every time your brain is
making a category as a way of explaining sense data in order to act on it,
your brain is creating a whole set of opportunities or possibilities or
possible futures. And each time your brain creates a category it may not look like
any other time. So when your brain makes a category for anger in one
situation, that may look very different than the category that it makes
for anger in another situation or for fear or any other emotion category that your
brain is capable of making.

So emotion categories, just like people who are developing respiratory illnesses
or not, are populations of variable instances and in fact this is a concept that Darwin
introduced in the origin of species,  and that the biologist Ernest Mayer
calls ‘population thinking’.
So the big takeaways here are first that when it comes to brains and
bodies, whether we’re talking about emotion or we’re talking about who gets sick
from exposure to a virus, variation is the norm. The common cold studies show really
clearly that, you know, the mind and the body are linked not in some vague
metaphorical way but in a real probabilistic biological way. What we think what we
feel, how we experience the world and who we experience it with
translates into vulnerabilities or resilience to illness.

Se don’t really know how mental events like the experience of fear or anger or awe
or gratitude are transformed into physical conditions like immune function, but this is
something that scientists and maybe even some of you
are working on.
And I guess the the thought that i would leave you with is an absence of
knowing everything is not the same as knowing nothing. The common cold
project clearly suggests that at least four cold viruses, one of which was a coronavirus.
And so this may generalize to other viruses too, like covid19, that psychosocial
factors leave a brain more or less able to regulate the pro-inflammatory cytokine response
upon exposure to a virus.
Other research has established a relationship between other biological conditions and
stress and emotion that are really important.  For example, people who are chronically
stressed have shorter telomere lengths and this means chronic stress increases
pro-inflammatory cytokines and also encourages a poorer antibody response to vaccines.
People with shorter telomeres, particularly in white blood cells that help
mount an immune response to pathogens, have an increased risk in respiratory illness.

Now if you want to find out more about these ideas, some of which i know
sound pretty outrageous to you, but i can tell you that they’re based on the best available
science that certainly I know about, you can look at my book ‘How Emotions are Made –
the Secret Life of the Brain’.
As well, for a fuller discussion of these ideas and the science behind them
you can look at my new book, which comes out next week on Nov 17/22 called
‘Seven and a Half Lessons about the Brain’.

I’m really sorry that I couldn’t be with you in person, well virtually in person,
today but if anyone would like to reach out to me please email me at
l.barrett at northeastern northeastern.edu
If you google my name you can find the email address easily.
Thank you again for listening to my talk and I hope the rest of this conference is
informative and useful to you.

HOW EMOTIONS ARE MADE
– SERIES  FEB 21, 2017
1. Cartoon Science

When I was growing up I loved watching cartoons. You can learn some pretty
surprising things about science by watching cartoons.
Chemistry for example is all about mixing colorful liquids and test tubes
until they explode. Cartoon physics is about running off a cliff and not
falling until you look down.  Scientifically got its own cartoons.
These are little characters in your brain – one for anger, one for sadness, for
fear, disgust and joy.  Unlike the chemistry and physics cartoons, emotion
cartoons are inspired by an actual scientific theory. And how emotions are
made I call this the classical view of emotion.

Here’s the basic idea. Some event happens in the world, like maybe you see
a snake slithering towards you. The snake supposedly turns on a circuit
in your brain where a single emotion lived, like a little cartoon character
operating some controls every time you feel fear.
For example, supposedly your fear neurons triggered, likewise these neurons
are supposed to trigger fear in every other healthy human on the planet, and
also in monkeys and rats and crayfish and other all sorts of other
creatures.  Fear neurons are supposed to control a distinct bodily response your
heart’s supposed to race. You’re supposed to sweat, you’re supposed to breathe
really quickly. This is all supposed to cause a very distinctive feeling like
terror and maybe an action like running or trembling. And of course a facial
expression that everyone in the world is supposed to recognize. This cartoon
combination in the face and the body and the brain is said to be a fingerprint
for fear that you could recognize anywhere. Likewise other emotions are
supposed to have their own fingerprints.

This theory has been around for a very long time. People believe it even though
it’s very cartoonish. And they believe this cartoonish story about emotions
because that’s how emotions feel to us. But science has taught us again
and again that our experiences are a poor guide to how nature actually works.
We see the Sun across the sky each day, but this doesn’t mean that the Sun
actually revolves around the earth. Scientific revolutions in physics and
chemistry over time have revealed a world that defies common sense and now
the same is happening in the science of emotion.

How Emotions are Made
2. Ask How, Not Where

Individual emotions do not live in specific parts of your brain.  You
wouldn’t know that from news stories which repeatedly claimed that fear for
example lived in a brain region called the amygdala and that disgust lives in
another brain region called the insula.  And this is supposed to be true whether
you’re a human or a fruit fly.  Such claims are based on an outdated
understanding of brain function that goes something like this:  your brain is like a
machine with independent pieces and each piece has its own function. So it’s kind of
like a collection of separate mental organs.  There’s one organ for each kind of an
emotion that these are assumed to live in the very ancient animalistic parts of
your brain.  Thoughts and memories and beliefs supposedly live in other more
highly evolved brain parts that allegedly control the emotion part.

Modern neuroscience actually began with these beliefs as scientists searched for
different parts of the brain that held dedicated circuits for anger and fear
and happiness, for thoughts and beliefs and memories and so on. But in recent
years we’ve discovered that a brain is not really a collection of separate mental
organs. It’s actually a vast structure containing billions of neurons that are always passing
information back and forth to each other.  This one structure can take on billions
of different patterns so emotions and really all mental events are constructed
by your whole brain as vast networks of neurons work together. This changes the
kind of scientific question we ask. We no longer ask where emotions live in the
brain but instead we ask how the brain makes emotion.

How Emotions are Made
3. Core Systems

Another surprising thing I learned as a neuroscientist is that brain networks
serve more than one purpose. Here’s an example of one core brain network and
here’s evidence from a handful of brain imaging studies showing that this one
network plays a role in making emotions, in making concepts and memories and an
imagination and in perception and even in chronic pain.
This similarity can be tricky to see if you’re not used to looking at brain imaging results,
so I’m circling the similarities here for you.
Here’s another core brain network: the colorful blobs in this image indicate
regions in this network that have increased their activity in almost 6,000
studies of various mental events.  So a core brain system is one to many mapping.
A single brain network contributes to many different mental events. In fact my
lab has collected hundreds of studies of emotion where tens of thousands of
people have their brain scanned while they were angry, sad, afraid and so on.

Here’s a statistical summary of the brain networks that participate in making fear.
The thing to know here is that this is not a photograph of what  fear looks like
in the brain.  It’s more like a statistical average no one brain
actually needs to look like this in fear. Now let me show you the recipe for this
average using seven core networks that neuroscientists have discovered in the
brain. I’m displaying the results on a circle with one line representing the
activity of each core brain network.
So as you see a mark way out here means the average recipe for this emotion
contains a lot of that network and if you see a mark way down here it means
that only a small amount of this network is needed for the average recipe. This
shape depicts the average recipe for fear, so when someone has an experience
of fear on average all seven networks are involved to some degree, even
networks for vision and hearing.
Likewise, the average recipe for anger includes all networks in some proportion, and this
is true for every other emotion that we study. Here I’m showing you disgust and
sadness.

So think about brain networks like their ingredients in your kitchen. You can
begin with flour, water and salt and create diverse foods like cookies or
breads or even sauces. We can even make non-foods like glue. No ingredient is dedicated
to any particular food. Likewise no brain network is dedicated to any specific
function.  Your mind is a computational moment in your brain and your brain
network work together to create a rich and varied emotional life.

How Emotions are Made
4. Making Emotion

To make an emotion you need core brain networks to do a couple of things. First,
your brain has to represent all the stuff going on inside your body – your
heart beating, your lungs filling and emptying, your stomach digesting food,
your hormones rushing through your bloodstream and the workings of your
immune system. This activity produces a spectrum of basic feeling from pleasant to
unpleasant and from calm to jittery. Even neutral stems from these physical
changes.
Second your brain has to remember your past experiences. Here’s a
way to think about it. Your brain spends all of its time locked in a dark silent
box called your skull.  Its only clues about what’s going on in the world around you
come from scraps of information from your senses – sights, sounds, smells, touches
and taste.  Your brain has to figure out what these scraps mean so it knows how to keep you
alive and well. Do you need to run? Do you
need to laugh? And so on.

Its only tool for answering this question is your past experience so your
brain has access to the sensory effects without actually knowing what the causes
are. It has to guess at what the causes are. What did similar scraps of
information mean the last time you were in a similar situation. Your brain is
taking guesses using your past experience and it uses the momentary
information from the outside world to either confirm those guesses or to
modify them. The same process for deciphering the outside world also works
for figuring out what’s going on inside your body. If you have a dull ache in
your stomach does it mean that you’re hungry, that you’re sick, that you’re
angry. that you’re missing someone.
Again your brain is using past experience to guess what caused this situation. So you
have an emotion. When your brain uses past experience to give your sensations
meaning, such as an emotion may be the last time your stomach aches like this in a
similar situation – you were angry, maybe you clenched your fists, then
started to breathe deeply. Your brain may guess that your current stomachache has
a similar cause of anger and needs a similar action.
Likewise when you see emotions in other people, it’s because your brain uses
past experience to give emotional meaning to their smiles and frowns and laughs
and hand gestures and body postures and so on.  Sometimes a scowl means anger
but other times the same scowl means that someone is concentrating really hard.

How Emotions are Made
5.  Degeneracy

One of the most surprising things I’ve learned as a neuroscientist is that fear
or any other mental event is not created by only one set of neurons. Instead
combinations of different neurons can create the exact same feeling of fear.
Neuroscientists call this principle ‘degeneracy’.  That means many to one.
For example, take a look at this face.  What emotion do you see? It’s enjoyment.
This facial expression looks very different from this facial expression which is also
enjoyment. So they’re both enjoyment but the facial expressions are very different.
This is an example of degeneracy and is very common in everyday life. Have you
ever made pancakes, for example.  You probably have a favorite recipe. Mine
includes buttermilk. When I’m out of buttermilk I’ll sometimes use sour cream
or else sometimes use whole milk mixed with a little bit of lemon. The end result is
always the same, pancakes that taste a little tangy.

That’s an example of degeneracy in my kitchen.  Degeneracy in the brain means that many
combinations of neurons can produce exactly the same emotion.  Here’s a study
of fear from my lab.  We scanned people’s brains as they were experiencing fear.
What I’m showing you here is the result on an inflated brain image so that you
can better see the results. Here’s one example of the brain activity during fear and
here’s another example.  Obviously they’re not the same.  This is an example
of degeneracy in the brain.
Variation of this kind is the norm in how the brain works. Here’s another
example of degeneracy: identical twins with the disease that destroyed a key
part of their amygdala when they were 12 years old. The missing part is outlined
in color.  Both women have exactly the same brain lesion and they live in
exactly the same environments and they have exactly the same genes.  But they differ
in their ability to feel and perceive fear. Twin one on the left can only feel fear under
extreme circumstances in very specific conditions, whereas twin two has normal
fear experiences. Her brain has degenerate systems to make fear even though
she doesn’t have a working amygdala.

How Emotions are Made
6. Emotion in the Media

So how can you tell whether to trust a news story about emotion or not. One clue
is whether the story talks about parts of the brain as if they have dedicated
functions, like this is where fear lives and over here is where happiness lives.
This is simply the wrong approach, whether we’re talking about a human or
an earthworm.
Here’s another clue. If the story implies that parts of your brain are off until they’re
suddenly turned on, then you know you should be suspicious.  This old idea that you
only use 10% of your brain is really for science fiction stories and cartoons. No part of
your brain is ever truly off. Your whole brain works all the time, but different neurons
are more or less active. They pass more or less information to one another at
different times making different brain patterns.

How Emotions are Made
7. Implications

How do you raise your kids to be emotionally intelligent? How emotions are
made explain some simple things that you can do every day. Here’s one
example: even before children can speak you can look them straight in the eye,
widen your eyes to grab their attention and then use emotional words when you
speak to them, to describe your own experience and to label… Research
shows you’re actually building brain connections in your child’s head when
you do this. That will make them better students and better able to navigate the
social world.
Words are powerful. They affect the wiring of the brain for good and for bad.
As your children get older they will encounter bullying in school, even
name-calling and other verbal bullying, that can have adverse measurable effects on
the brain if it goes on for long enough.  It can cause neurons to die and brain
regions to shrink. The result can be compromised immune system and illness.
Obviously this interferes with academic achievement. Sticks and stones may break
your bones but names really can hurt you.

Most people believe that women are more emotional than men. Shelves full of
popular books portray the stereotype of the fact but actually it’s a myth. Women
sometimes do move their faces more when they’re experiencing emotion than men do,
but women on average move their faces more in general than men do – not
just when they’re emotional. Even powerful women have to deal with gender
stereotypes regarding emotion.
So for example, Madeleine Albright, the first female US Secretary of State, had
to work hard early in her career to keep her voice unemotional so she could be
taken seriously. Supreme Court justices Elena Kagan and Sonia Sotomayor
encountered stereotyping during their confirmation hearings regarding whether
they’ve let their innate emotionality steer their judgments towards too much
empathy. Emotional stereotyping of women can be so subtle that even people who
are aware of a stereotype don’t notice when they’re doing it. Studies show that
women’s spatial movements are attributed to something personal about them
whereas the same movements by men are blamed on the situation.
So for example, if we see a woman scowling and we see a man scowling
we assume that the woman is scowling because she’s a bitch, and we assume that
the man is scowling because something bad just happened in the environment
and his scowl is reflecting his displeasure at the situation.
Women are punished for being too emotional or not emotional enough, so women are
punished for expressing anger that would be considered normal for a man. For
example, if a woman expresses anger, she’s usually seen as out of control, as less
effective, and she will be paid less.  Her yearly income will be lower than a man
who expresses emotion in a similar way. When a woman is stereotyped, say
she’s the only female in a meeting and nobody is paying any attention to her
words, which I can tell you actually does happen, she often can take one of two actions –
she can stay quiet about it and then be ignored basically, or even worse than a man
repeating her comments, and then he gets the credit for them, or she repeats
herself probably louder or more stridently than she would otherwise, and then she’s
seen as really pushy. In other words, she reacts to the stereotype but doesn’t call it out.
A more effective approach would just be to calmly point out the stereotyping.

Physical health and mental health are not separable. It’s very difficult to be emotionally
healthy if you’re not also taking into consideration your physical health.  When
people ask me what are some basic things I can do to manage my emotional health
better, my first question to them is are you sleeping enough? Are you eating enough to
get constant nutrition throughout the day? Are you getting up and moving your
body occasionally, are you exercising on a regular basis?

At the risk of sounding like a mother, I can tell you as a neuroscientist that all of these things
make it much easier for your brain to control your body, and your feelings come
from the sensations in your body and how you make meaning of those sensations.
But there’s a lesson here, I think, for everyday life, and that lesson is your
you will have much less distress if you organize your life in such a way
to maximize your physical health.
So in much the same ways, you might save money today for a rainy day in the future
making investments in your physical health today, we’ll have payoffs for your
emotional health tomorrow/

How Emotions are Made
8. Simulation

Think about the last time someone handed you a juicy red apple. You reached out
for it, you took a bite, and you probably experienced a tart flavor. During those
moments neurons were firing in your brain to produce your movements and to
create all your sensations of the apple, like its red color with a blush of green,
the smoothness of it against your hand, the crisp floral scent, the audible
crunch when you bite into it, and its tangy taste with a hint of sweetness.
Now here is the very cool thing. Just now, when I said the word ‘apple,’ your brain
responded to a certain extent as if an apple were actually present. That is, your
brain combines bits and pieces of previous apples that you’ve seen and
tasted. this is called simulation. If you had a real apple in your hand this
simulation of the feel and smell and taste of the apple will happen at the
moment before you bite the apple.
So basically your neurons in the visual parts of your brains and in the parts
that code for taste and so on start to fire in advance of you actually biting
into the apple. Using past experience, your brain predicts what your experience
will be like. As information arrives from your taste buds, your brain compares it to the
simulation. If the real apple turns out to be a little sweeter than your brain
predicted, your brain might adjust its simulation so that you taste that
unexpected sweetness. But your brain might also just ignore the difference
so that you don’t notice it.
The apple example is no different from what you’re doing right now. You might
think that you’re sitting and listening to me speak, reacting to my words but in
fact, your brain is using its past experience to predict every single word that I say.

Now let’s apply this logic to emotion. Suppose you’re walking alone in the forest
and you hear some rustling of leaves. As always, your brain will launch
predictions. In this example, your brain will predict that there’s a snake nearby.
It begins to simulate the sights and sounds of a snake and prepares your body
for actions to run. These predictions translate into feelings. For example, your heart
rate goes up, and maybe you begin to breathe more deeply, and you might feel agitated.
So what happens next? Well, there are three possibilities. Maybe the snake slivers out
from the bush, so the sensory input matches your prediction, and your running in fear
becomes your brain’s best guess for what just caused those sensations based on
your past experience of the last time you were walking in the forest. But, maybe no snake
is present and the leaves were just rustling because of the wind. In this case, your
brain might correct its prediction and you won’t see the snake, but because of
your original simulation, you’ll still feel agitated and you’ll make sense of
that feeling in some other way.
Here’s the really strange part. It’s even possible that when there’s no snake
present, you will see one anyway. It’s similar to experiencing an optical
illusion. Like this one – there is no white square in this picture but your brain is
simulating one, so you actually see it.

How Emotions are Made
9. The Cascade

Imagine a bunch of neurons firing in some pattern. Now along comes a smaller
group of neurons that are a little better connected to one another, and they
say we can represent this pattern a little more efficiently and so they do.
And let’s imagine this happens for every sense that you have – seeing, hearing,
touching, and so on.
So in this example, I’ve only depicted three different senses. This sort of
thing happens all the time in your brain for efficiency, so smaller and smaller
groups of neurons summarize what other neurons are doing. Eventually, a few big
honking neurons represent all of these other summaries together at the front of
the brain. They summarize an entire cascade actually so you’ve got this pattern of
neurons and smaller neurons firing, and then some other neurons summarize that pattern
and then some other neurons actually summarize that pattern, and so on and so forth,
fewer neurons being used each time.

This is actually how the brain works, and we call this learning. When the brain predicts,
the ‘Cascade’ is actually playing out in reverse. The biggest best-connected neurons
launch predictions, each of which has a cascade into finer and finer and finer predictions
as groups of smaller and smaller and smaller neurons all
along the way, fire in a different pattern until the cascade reaches the sensory and motor
regions of your cortex which actually have the smallest neurons fall.
So a simulation is one big cascade of prediction. As it turns out everything
you see, hear, taste, and feel come from these massive cascades of predictions.
Your brain is launching thousands of these cascades of simulation at every
moment, and some of them create emotions.

(small gramatical edits added KH)