Welcome back everybody for another deep dive.
This time we're gonna be tackling the free energy principle
in neuroscience.
Okay.
And this idea suggests that our brains
are like prediction machines
that are constantly trying to minimize
something called free energy.
Uh!
We've got an excerpt from a video titled
free energy principle explained
as our main source material.
Basically it proposes that the reality we experience
might be more of a controlled hallucination
than we realize.
Whoa!
What a fascinating concept.
The idea is that our brains aren't just
passively taking in information, you know.
Right.
They're actively predicting what we'll see,
what we'll hear, and even what we'll feel.
The sensory data that we do get just kind of confirms
or refines those predictions rather than dictating them.
That's a pretty wild way to think about
how our brains work.
Why would our brains evolve to function like this?
I mean, what's the advantage of living
in a prediction based reality?
Well, imagine our ancestors trying to survive
in a world that was full of danger
and incomplete information.
So, picture trying to spot a tiger
that's hiding in the jungle.
You're only seeing little glimpses
of its stripes through the leaves.
Oh, I see.
A brain that simply reacts to those fragmented visuals,
just those little stripes wouldn't last very long.
That's true.
A more sophisticated system would definitely be needed
to survive in that kind of environment.
Exactly.
Our brains had to evolve to become expert model builders.
You know, filling in the gaps,
predicting what's likely to happen next.
It goes way beyond just simple stimulus and response.
So it's like the brain is taking those stripes
and combining them with its knowledge of tigers,
their shape, their behavior, you know,
the danger they represent all
to create a complete picture,
even when it doesn't have all the information.
That's amazing.
It is.
And this is where this idea of free energy comes in.
It's essentially a measure of surprise
or tension in the brain.
When the sensory data that we actually get
doesn't match our brain's existing models of the world,
that creates this free energy.
And you know, like any efficient system,
the brain wants to reduce that energy.
So are you saying that our brains are constantly trying
to explain away surprises
by sitting them into our existing worldview?
Yeah.
That's kind of unsettling if you think about it too much.
Well, it's not necessarily about ignoring reality,
but more about trying to make sense of it
with the information that we have.
Think of your brain as a judge weighing evidence, right?
Okay.
On the one side, you've got the sensory data,
what you see, what you hear, and what you feel.
And then on the other side, there are your prior beliefs.
These beliefs are shaped by evolution
and your own experiences.
It's like the brain is trying to solve a puzzle.
It's trying to fit those pieces of sensory data
and those pieces of belief together
in a way that makes sense.
That's a great way to put it.
So the brain's constantly trying to reconcile
those two sources of information,
and this balancing act is what drives our perception.
The brain uses its models
to create explanations for things.
It checks those explanations
against incoming sensory data,
and then it refines its understanding
based on the results.
You keep mentioning these models that the brain uses.
What exactly are those?
Are we talking about like miniature dioramas in our heads?
Not quite.
This is where we get to the brain's incredible ability
to handle complex information.
We have these things called latent neurons,
and they aren't directly connected to sensory input.
Instead, they represent abstract concepts and causes
like at different levels of detail.
Abstract concepts.
What does that even mean in terms of brain activity?
Okay, so think of a 3D scene in a program like Blender.
You've got all these sliders controlling things
like the position of an object, the color, the lighting.
Those sliders are like our latent neurons
representing high level features of the scene.
Okay, so the rendered image in Blender
is like the complex sensory data that our brain receives.
Yes.
And then the latent neurons are like the controls
that determine what that image looks like.
Exactly, and just like we learn
which slider combinations make sense in Blender, right?
Our brains learn which combinations
of latent neuron activity are most likely
to occur in the real world.
Okay.
And these learned probabilities become
what we call our priors.
Our priors.
Our preconceived notions about what's plausible.
But here's what I don't get.
We don't perceive the world by adjusting sliders, right?
Right.
We get that finished image.
We get the sensory data, and then we have to figure out
what caused it.
Yeah.
How does the brain reverse engineer that whole process?
That's where the recognition model comes in.
Ah, okay.
And this works in the opposite direction
of the generative model.
So given a sensory input, it tries to figure out
the most likely combination of latent neuron activity
that could have caused it.
It's like looking at a cake and trying to guess the recipe
based on its appearance and taste.
So it's basically an educated guess that the brain makes
and then can refine over time.
Exactly.
It's amazing to think our brains are constantly
making these calculations without us even realizing it.
That's right.
And the brain uses this back and forth
between the generative and recognition models
to constantly try and minimize that free energy
that we talked about.
You're telling me that something as simple
as seeing a chair involves this complex dance
between models and predictions and comparisons
with sensory data, that's kind of mind blowing.
Absolutely.
And this process isn't just about those split second
perceptions, you know, over time our brains refine
both their generative and recognition models.
They're learning to predict and explain the world
around us more accurately.
So it's like our brains are always learning and adapting.
Constantly.
I see.
This is all starting to click.
We're not just passively absorbing information.
We're actively shaping our reality
through this ongoing process of prediction and refinement.
That's a pretty powerful concept.
It is.
And to illustrate this in action,
let's revisit that illusion that you mentioned earlier,
that rotating mask.
Oh, right.
You showed us this mask that looked convex,
even when we knew that it was actually concave.
It was like our brains just totally
refused to see it any other way what was going on there.
Well, that illusion, that really highlights
how strong those priors can be.
They can sometimes even override contradictory sensory
information.
You know, our prior belief that faces are convex,
built up over, I mean, our whole lives.
It's so strong that the brain often assumes
unusual lighting rather than a concave face.
So it's like our brain is saying, OK,
I've seen thousands of faces and they've all been convex.
Even though these shadows are telling me otherwise,
I'm going to stick with what I know.
Exactly.
So from a free energy perspective,
it's less costly for the brain to stick with this fundamental
prior than it is to reinterpret that sensory evidence.
It's always looking for that simplest explanation.
That's a fascinating insight into how our brains work.
It makes you wonder just how much of what we perceive
is actually influenced by these really deeply ingrained
priors.
It's a question philosophers and neuroscientists
have been debating for, well, ages.
The free energy principle offers a new way
to think about these fundamental questions
about perception, consciousness, and really reality itself.
This whole concept of free energy
is really making me think differently about how my brain
operates.
So we've been focusing mostly on how we see the world.
But does this theory apply to other things, too?
Sure.
Like learning or even consciousness?
Well, that's one of the remarkable things
about this free energy principle.
It provides this framework for understanding not just
perception, but also things like learning, action,
and even consciousness.
Hold on.
Are you saying that our conscious experience is just
a byproduct of our brains trying to predict the world?
That's a pretty huge leap.
Well, it's a bit more nuanced than that.
The idea is that conscious awareness
might emerge from the brain's need
to represent its own internal state,
so its beliefs and uncertainties,
as part of this overall model of the world.
So instead of just predicting what's happening out there,
the brain also needs to predict what's going on internally.
That's the idea.
I'm trying to wrap my head around this.
Can you give me an example, maybe?
Sure.
So think about reaching for a cup of coffee.
Right.
Your brain predicts what that movement should feel like,
what the cup should look like as your hand gets closer,
and so on.
Right.
And if the feedback from your senses
actually matches those predictions,
then that free energy is minimized.
I see.
And you successfully grab your coffee.
OK, that makes sense.
Yeah.
But what if you misjudge the distance and knock the cup over?
Does that create a surge of free energy then?
Exactly.
So that unexpected outcome, that signals to the brain
that, hey, your model needs some updating.
Oh, OK.
Maybe you adjust your internal representation
of the cup's location, or you refine your motor skills
for future reaching, or even learn
to be more cautious around coffee cups.
Right.
So even our mistakes can help our brains learn and adapt.
That's pretty reassuring.
It is.
Every action we take, every interaction
that we have with the world, becomes an opportunity
to test and refine those internal models.
It's this continuous loop of predicting, acting,
getting that feedback, and updating our understanding.
So is that how consciousness fits into all of this?
Is it just the brain becoming aware of its own awareness?
Well, that's one of the intriguing ideas
that people are exploring.
Yeah.
Some theories suggest that this internal model,
so this representation of our mental states,
that's what actually leads to the subjective experience,
to the feeling of what it's like to be us.
It's like the brain looking inward
and modeling its own internal processes
as part of its overall effort to minimize that free energy,
to make sense of the world both inside and out.
OK.
This is starting to get really meta.
I'm starting to see how this theory connects
all these different aspects of our mental lives,
and we started with this simple idea
of the brain as a prediction machine,
and now we're talking about consciousness.
It's a testament to the potential of this theory,
I think.
It connects all these seemingly separate ideas
and really offers a fresh perspective on the human mind.
I agree.
We keep coming back to this idea of the brain
as this model builder.
It seems to be the underlying theme
that connects all these concepts.
I think that's a key insight.
If we are fundamentally prediction machines,
constantly trying to minimize surprise and uncertainty,
that really shapes everything from how we see and act
in the world to our beliefs and even our sense of self.
It has huge implications for how we understand ourselves.
Doesn't that mean that we're trapped in this world that's
just defined by our own predictions?
I mean, are our models just set in stone?
Not at all.
The free energy principle doesn't say that our models are fixed.
They're constantly being refined, updated, and even
challenged by new experiences.
And that ability to question our own predictions,
to embrace the unexpected, and to update our models based
on new evidence, that's what allows us to grow and evolve
and navigate this complex world.
That makes sense.
If our models were completely fixed,
we wouldn't be able to learn or adapt to new situations.
Our brains need to be flexible.
Absolutely.
That flexibility is essential for learning and adaptation.
So you mentioned earlier that the free energy principle
has connections to machine learning.
Yeah.
That sounds fascinating.
Can you tell me a little more about that?
That's an area where things are getting really, really
interesting.
The free energy principle is inspiring a whole new wave
of research in AI.
It's leading to the development of AI systems
that our brains can learn to predict, to generate,
and even to imagine.
So we're talking about AI that can not only process data,
but actually understand it and interact with the world
in a more meaningful way.
That's the goal.
We might be able to create AI systems that are not only
intelligent, but also adaptable, creative, and perhaps even
capable of experiencing consciousness,
all by drawing inspiration from those principles that govern
our own minds.
That's both incredibly exciting and a little bit frightening.
I'm not sure I'm ready for conscious AI just yet.
But it definitely sounds like a topic for another deep dive.
Absolutely.
OK, so we've been talking a lot about the theoretical side
of the free energy principle.
Right.
But what does this all mean for us in practical terms?
How can we use this knowledge in our everyday lives?
That's where the real power of this theory lies, I think.
It invites us to become more aware
of our own internal models and how they shape our perceptions
and our decisions.
It's not about becoming slaves to our predictions,
but about understanding them.
Questioning them, and even challenging them when necessary.
So it's about being more mindful of our own biases
and assumptions.
Yes.
Recognizing how our past experiences
might be influencing how we're interpreting the present.
Exactly.
Imagine being more conscious of those biases
that creep into your thinking and recognizing
how your past experiences might be coloring
your interpretation of the present.
It's like being able to step back and observe
our own thought processes to see the code running
in the background that's shaving our reality.
I like that.
Yeah.
And with that awareness comes the potential for change.
We can actively seek out new experiences,
challenge our preconceived notions,
and expand the boundaries of our internal models.
So instead of just minimizing free energy,
we can actively seek out a little bit of good energy.
I love that.
The kind of energy that comes from learning, growing,
and pushing the limits of our understanding.
That's a great way to think about it.
It's about embracing the unexpected,
welcoming the challenge of updating our models,
and realizing that the journey of understanding
is an ongoing process.
As we've been talking, I keep thinking back
to that mask illusion.
Yeah.
It's a powerful reminder that our perceptions aren't always
an accurate reflection of reality.
They're shaped by this inner play of sensory input
and those preexisting beliefs.
It is a very powerful example.
It highlights how our brains use prior information
to make sense of the world, even when it
leads to a slightly distorted view of reality.
So if our perceptions can be so easily influenced
by our priors, does that mean we can never truly
trust our senses?
Are we forever stuck in a world of our own making?
I'm starting to feel a bit like I'm living in the matrix.
Well, that's a common concern.
But it's not quite that bleak.
OK.
Remember, our models are constantly being refined.
We can learn to recognize our own biases,
be more critical of our interpretations,
and seek diverse perspectives that
challenge our assumptions.
So it's about becoming more discerning observers
of our own reality, recognizing that there's always
more to learn, more to explore, and more ways
to refine our understanding.
It's like a lifelong quest to improve our mental models.
Yeah.
It's like a lifelong quest to improve our mental models.
It sounds like you're saying that by understanding
those principles that actually govern our own minds,
we can unlock new levels of creativity and empathy,
maybe even wisdom.
I think that's a beautiful way to put it.
The free energy principle helps us
see that we're not just these passive receivers of information.
We are active participants in shaping our own reality.
It's a bit like we're all artists,
constantly painting our own picture of the world.
And the more that we understand about the tools and techniques
that we're using, the more masterful
those creations can become.
This has been such an eye-opening conversation.
I feel like I've gained a whole new perspective
on how my brain works.
I'm glad to hear that.
That's the beauty of exploring these ideas, right?
It challenges us to think differently about ourselves
and the world around us.
So as we wrap up our deep dive into the free energy
principle, what's like the one key takeaway you
hope our listeners will remember?
I think the most important thing to remember
is that our brains are incredible prediction machines.
They're constantly working to make sense of the world.
But those predictions aren't always perfect.
They're based on our past experiences, our beliefs,
and sometimes even our biases.
So it's not about rejecting our predictions,
but about recognizing that they're just that, predictions,
not necessarily the absolute truth.
Exactly.
We can learn to question our assumptions,
to seek out new information, and be open to updating our models.
That's how we grow and evolve.
This whole conversation has made me realize just how much power
we actually have in shaping our own reality.
We do.
And the more we understand about those principles that
are governing our minds, the more effectively
we can actually wield that power.
Well, on that empowering note, I think
it's time for us to resurface from this deep dive
into the fascinating world of the free energy principle.
It's been a pleasure exploring these ideas with you.
To all our listeners out there, thank you
for joining us on this journey.
Remember to keep those brains budding.
Keep questioning, and keep exploring the world
with curiosity and an open mind.
Until next time, happy predicting.