Chapter 22: Embodied Resonance

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Welcome back to the Deep Dive.

Our mission here is to take deep, complex research and, well, deliver the most important insights directly to you, cutting through all the noise and the jargon.

And today we are undertaking a really fascinating deep dive.

We are.

It's a crucial chapter called Embodied Resonance by Vittorio Galezza and Corrado Sinigaglia.

And this is a foundational text within a hugely influential area of modern cognitive science known as 4E cognition.

That's right.

And when we talk about 4E cognition, we're referring to this idea that the mind is embodied, embedded, inactive and extended.

This chapter, Embodied Resonance, is focused squarely on that first E for embodied.

The authors are presenting a very empirical but also, you know, a highly philosophical argument about how we understand other people.

And the central idea here, which I think really flips the script on a lot of traditional psychology, is that social understanding, so the ability to know what another person is doing, it doesn't rely on some kind of abstract logical inference.

It relies on a physical shared mechanism.

Precisely.

The core mission of this deep dive is to unpack their approach, which they call Embodied Simulation or E .S.

E .S.

OK.

They argue that understanding what someone else is doing actually relies on reusing our own internal motor systems.

So we don't deduce your beliefs to figure out your action.

We literally simulate your action using the exact same neural resources we'd use to do it ourselves.

OK, let's unpack that a little more, because that sounds like a radical shortcut to social knowledge.

And they're suggesting this overlap, this reuse provides a common ground at two different levels.

Absolutely.

Two distinct but linked levels.

The first level is the functional one.

Right, the mechanic.

Yeah, what the brain is actually doing.

The same neural circuit is functional for both doing the action and watching the action.

Yeah.

But the more revolutionary claim, the real central conjecture here, is that this common ground also exists to the deep phenomenological level.

The experiential level.

Exactly.

It impacts what we actually experience.

That there's an experiential overlap between doing and seeing.

So when you say phenomenological, are we talking about the actual raw feeling of movement or just how we process the information?

I mean, does watching someone run a marathon feel even a tiny bit like I'm running it?

That is the ultimate question.

It's what the authors are driving toward and it's what gives this deep dive.

It's well, it's resonance.

It elevates the whole discussion beyond just neural wiring and into the nature of consciousness itself.

OK, so if we're going to trace this whole argument from the ground up, we have to start with the hardware that makes this all possible.

We do.

We have to start with mirror neurons.

So what's the road map for today?

We'll start with the discovery of these mirror neurons, their key properties and especially their role in encoding action goals.

Then we'll get into the theory defining embodied simulation and why the authors insist on defining simulation as reuse rather than, you know,

the traditional idea of resemblance.

And finally, we'll see how this whole concept, which is driven by what they call representations that are bodily in format,

acts as this essential building block for social cognition and how it shapes our phenomenal experience of action.

Let's do it.

Let's start with that discovery that, as you said, really shook the foundations of neuroscience back in the 90s.

Mirror neurons, where were they first found and what makes them so remarkable?

They were first identified in the macaque monkey back in the early 1990s.

Specifically, researchers found them in the ventral premotor cortex or PMV, an area called F5.

And that area is important because it's a core part of the motor system.

It's involved in planning and controlling goal directed hand and mouth movements, things like grasping.

And their key property, the mirror property, what is it?

Property is it's stunning in its simplicity, but it's so profound.

These neurons fire when the monkey performs a specific goal directed action like grasping a peanut or tearing piece of paper.

Right.

Standard motor neuron.

But and this is the incredible part, the exact same neuron also fires when the monkey is completely still and just observing another individual like an experimenter performing that very same action.

Wow.

So it's an internal observation execution matching system.

Exactly.

It automatically maps what is seen onto a plan for what can be done.

And the sources point out this isn't just one isolated cluster of cells in area of five.

This is a whole network.

Oh, absolutely.

It's a circuit.

Subsequent research really expanded the network.

They found mirror properties in the posterior parietal cortex, which is connected directly with F5 forming this crucial parietal frontal circuit.

OK.

And the mirroring properties go even deeper into the classic motor hierarchy.

They show up in the primary motor cortex, which is F1 and even the dorsal premotor cortex.

I noticed they specifically mentioned pyramidal tract neurons, PTNs.

Those are the main output cells sending motor commands down to the muscles.

Right.

Finding mirror properties there seems hugely significant.

That is absolutely key.

It suggests the mirroring isn't just some input phenomenon.

It's integrated deep within the action planning architecture itself.

PTNs in F5 and F1 were also found to respond to action observation.

So the system is primed all the way down the chain.

It is.

And what's fascinating and a detail that often gets missed is that while most of these neurons showed an increase in firing when observing an action,

a subset of them actually showed a suppression of firing.

A suppression.

So they quiet down when you see an action.

Why would that happen?

Well, that inhibitory effect is likely a crucial safety mechanism.

Oh, to stop you from actually doing the action.

Exactly.

If the full motor plan is being run internally while you're watching, the system needs a break,

an inhibitory signal to prevent you from just involuntarily mimicking every movement you see.

Right.

You don't want to be a puppet to everything you observe.

Imagine watching someone grab something hot.

You don't want your hand to reflexively try to do the same thing.

The brain is managing this dual activity very, very carefully.

So it's an incredibly complex system, an excitatory mirroring function combined with an inhibitory safety function.

And we find these mirror like functions extending to coordinate even very basic social interactions.

They were found in neurons in the lateral intraparietal area or L .I .P., which is involved in eye movements.

Shared attention.

Precisely.

These neurons fire when the monkey looks in a direction, but also when it sees another monkey look in that same direction.

It directly helps establish shared attention, suggesting this whole system helps build social understanding right from the very beginning.

OK, so this brings us to one of the most important distinctions of the whole chapter.

The authors argue that these mirror neurons are not just encoding movements like muscle twitches.

They are encoding the why, the purpose, the action goal.

Yes, that distinction is central.

And the evidence for goal encoding is just so elegant.

If mirror neurons only encoded raw movement, they should fire based on muscle contraction patterns, but they don't.

So how do we prove that?

How do we know it's the goal?

Well, first, they respond to the same action outcome, say, getting a piece of food,

even when the action is performed with completely different body parts, like using your hand versus your mouth.

Exactly.

If it were just about muscle contractions, the neural signature for a precision grip with your fingers would be totally different from a bite.

But the mirror neuron response, which is tied to the goal of getting the food,

stays robust.

And this even works with tools.

The source material highlights this amazing experiment with pliers.

Yes, this is a spectacular piece of evidence.

Using reverse pliers requires the opposite finger movements.

You close your fingers to open the pliers.

And yet the mirror neurons still track the goal, securing the object.

They completely ignore the specific muscle movements to focus on the end result.

That makes the system incredibly flexible.

But I think the even stronger evidence comes from when you have the same movement, but for different goals.

Absolutely.

The third powerful line of evidence shows that the firing profile of these neurons changes dramatically when the same bodily movements are directed toward different goals.

So take a simple reaching arm movement.

OK.

When that arm movement is for grasping food to eat it, you get one neural signature.

But when the exact same reaching movement is used to grasp that same food to place it in a container,

you get a recognizably different neural signature.

So the neuron isn't just firing because an arm is moving through space.

It's firing because the brain is calculating the ultimate intention behind that movement.

That is the definition of goal oriented encoding.

And it goes even further.

This principle extends across different senses, which confirms how abstract the goal representation is.

Mirror neurons were shown to respond even to just the sound of an action, the sound of paper tearing or a peanut cracking without any visual input at all.

None.

The sound alone triggers the motor representation of the goal.

So the system is fundamentally goal oriented, no matter how the information comes in and moving from monkeys to us, the sources confirm humans have a very similar system and it's so metatopically organized.

We do.

Neuroimaging in humans consistently shows the shared activations in the ventral premotor cortex,

the inferior frontal gyrus part of Broca's area and the inferior parietal lobule, all corresponding to the monkey areas.

And so metatopically organized.

That means it's mapped out on our motor cortex like a little body.

Right.

Precisely.

The research by Buccino and his colleagues in 2001 confirmed this beautifully.

The same brain regions that light up when you perform an action with your hand or your mouth or your foot are the same ones that light up when you watch someone else use their hand or mouth or foot.

Exactly.

You watch someone kick a ball.

The foot area of your premotor cortex engages.

You watch someone talking.

The mouth area engages.

Our brain maps the other person's action directly onto our own physical action map.

OK, so the discovery of this motor ratcheting system immediately raised a huge question.

Why is this hardware there?

And Galiz and Senegalia, along with Goldman, were quick to propose it must be fundamental to how we understand each other.

Right.

The initial hypothesis back in 1998 was that these mirror neurons offered a primitive version or maybe a precursor of a simulation heuristic for understanding actions.

A kind of mental shortcut.

A mental shortcut.

Exactly.

They hypothesized that just observing an action automatically recruits a motor representation as if the observer were planning to do that action themselves.

And this internal rehearsal, this primitive simulation, allows for something they call retradiction.

Exactly.

Retradiction just means you can automatically identify the goal or outcome of the action.

You know what the person is doing without having to do all the heavy cognitive lifting of traditional mind reading.

So you don't have to logically deduce their beliefs and desires and intentions.

Right.

It's a motor shortcut to identifying the action's immediate goal.

This then evolved into the full theory of embodied simulation or ES.

But a key part of the Galiz and Senegal approach is defining what simulation actually is.

And they make this critical distinction between two views.

Simulation as resemblance versus simulation as reuse.

And this is the critical philosophical pivot.

The traditional view, which you see with theorists like Goldman, defines simulation as resemblance.

A mental state simulates another if it copies it or reproduces it or resembles it.

So the observer forms these pretend mental states, pretend intentions, pretend beliefs.

Yes, and they run them through their own psychological system to generate a matching state that resembles what the other person is thinking or feeling.

OK, so if I'm trying to figure out why you grab that mug, the resemblance view would say I have to sort of mimic your mental state about grasping it, trying to make my internal pretend state as close as possible to your actual one.

Precisely.

It emphasizes the outcome, the similarity between the two states.

But the ES view, championed by Gollies, endorses this alternative simulation as reuse.

What makes reuse so different?

Reuse focuses on the mechanism, not just the outcome.

In this view, simulation happens when the same fundamental mental state or process that is used for one purpose, like, say, executing an action, is reused for a completely different purpose, like observing or understanding that action.

Help me clarify this, because if the same neuron fires when I do an action and when I see an action, doesn't that automatically mean there's some resemblance between the two neural states?

Why do we have to switch to the term reuse?

That's a really crucial question.

The argument is that any resemblance that does exist between the two states must arise from the fact that the simulator is reusing her own processes.

Reuse is the fundamental driver.

Resemblance might be an outcome, but it's not the defining feature.

And why does the actual data from the mirror neurons favor this idea of reuse?

Because if it were all about resemblance, you'd expect a perfect or at least a very, very close match high congruence between the neural signature during execution and observation.

But what we actually see is that the motor responses and the visual responses of mirror neurons often have different degrees of congruence.

They're not always perfect copies of each other.

So if the similarity isn't always perfect, then defining the whole process by similarity is a bit shaky.

Exactly.

But the concept of reuse holds up.

What is common, what is consistent, is the activation of the underlying functional architecture.

The same brain networks developed for a hand grasp are being recruited.

The brain is recycling the resources it built for its own actions and applying them to social processing.

It's the recycling of that architecture that defines E .S.

So reuse emphasizes the brain's efficiency.

We have this amazing motor machine.

And instead of building a whole separate system for social understanding, we just co -opt the execution system for observation.

It's the ultimate evolutionary shortcut.

And this framing is so essential for the 4E perspective because it grounds the simulation not in abstract mental states, but in the physical functional structure of the motor system itself.

OK, so if E .S.

is defined by this reuse of the motor system, let's look at its scope.

The source material makes it clear this is much broader than just watching someone else act.

That's right.

E .S.

involves the motor system being co -opted for simulation in at least three big domains.

First, action mirroring, which we've covered.

Second,

motor imagery.

That's when you're imagining acting without actually moving.

We know that imagining an action recruits many of the same motor processes as actually doing it.

And the third one is object perception.

Yes.

Just looking at a manipulable object like a mug or a hammer often triggers immediate motor processes.

You get these representations of potential actions or affordances, even if you have no intention of picking it up.

The system is just constantly primed for interaction.

But we really need to clarify the term that defines all this.

Bodily formatted representations.

This is where the philosophy of 4E cognition really comes into play.

It does.

We have to tackle this core philosophical distinction between a representation's content and its format.

This sounds a bit abstract.

Why is the format so important?

Because the format imposes structural constraints on the representation that the content alone doesn't have.

Let's use the author's analogy to make this concrete for you listening.

OK, imagine you're planning a trip.

You have two different routes drawn as two different lines on a paper map.

The routes themselves are the difference in content.

Route A and route B.

Right.

Now, imagine those exact same two routes are represented not with lines on a map, but as a long list of verbal turn by turn instructions.

Turn left at the oak tree, walk 500 meters.

I follow.

The content route A versus route B is identical in both cases.

Exactly.

But the difference between representing those routes with lines versus with words is a difference in format.

The format is the medium, the structure of the representation,

and it constrains what can be represented and how.

A map has to obey the rules of geometry.

Verbal instructions are abstract.

So when Galiz and Senegalia say that, yes, involves representations that are bodily in format, what does that mean about their structure?

It means these representations share characteristic performance profiles that are associated with planning and executing physical actions.

And crucially, these profiles inherit the limitations.

The spatial, temporal and biomechanical constraints of the physical body, constraints that are totally absent in, say, a belief or a verbal instruction.

Right.

And there's overwhelming empirical evidence that these motor representations keep their bodily format, even when they're being reused for simulation.

Like with motor imagery again.

Exactly.

When people imagine acting,

say, walking up a flight of stairs,

the postural and temporal constraints of actual walking are preserved internally.

So if I imagine walking up a steep hill, the internal simulation takes me objectively longer than imagining walking down it, even though I'm lying perfectly still.

The internal simulation has to respect physics.

It absolutely has to respect the biomechanical constraints of your body.

And this applies to action mirroring, too, which brings us back to the monkey studies and the idea of peripersonal space.

The mirror system is spatially constrained.

Tell us more about that.

Well, single cell studies in the monkey's area F5 showed that mirror neurons only responded to the sight of grasping action if that action was performed within the monkey's peripersonal space.

The space right around its body where it can easily reach.

Exactly.

If the action happened too far away in what's called extra personal space,

the neurons often didn't fire.

So if the experimenter grasped food five feet away, the mirror neuron didn't respond in the same way, suggesting the action just wasn't available for simulation.

That's the key finding.

And here's the crucial detail from those studies by Caggiano and others.

The selectivity didn't just depend on the measured distance.

It depended on the monkey's actual possibility of reaching and acting on the object.

If the monkey was constrained or if the action was physically unreachable, the mirror neuron activity was inhibited.

So the body defines the format and the format defines the simulation.

That is a really tight loop.

And this is why the authors call this a moderate approach to embodied cognitive science.

They're careful to address critics who might say that by focusing on internal representations, they're sort of abandoning the body.

Right.

The snatcher version of embodiment where cognitive science just grabs the good bits and discards the actual body.

Exactly.

But Galiz and Senegalia clarify that defining a representation as bodily in format doesn't exclude the body.

It elevates the body.

The body's own constraints define that format, making the representation inherently bodily.

So we have the hardware, the mirror neurons and the framework, this idea of bodily formatted reuse.

Let's connect this to the fundamental function, how ES allows us to understand what others are doing.

The main claim is that this goal description, figuring out someone's goal, relies on reusing the observer's own motor processes.

And the empirical support for this is really robust.

It suggests your ability to understand another person's movement is just inextricably linked to your own proficiency with that movement.

So understanding correlates with motor expertise, not just visual expertise.

Precisely.

Studies have shown that mirror driven ES strongly correlates with motor expertise.

You see this with expert ballet dancers, elite musicians.

They show measurably greater motor resonance when they watch actions from their own skill set compared to non experts.

The more refined your internal motor library is, the better your simulation runs.

And what's amazing is that this understanding improves, even if you never visually see yourself perform the action.

If you train, your internal library gets updated and you can immediately apply that to observing others.

Which is confirmed by that work from Kaseel and Gies.

Exactly.

They show that training and action, even without any visual feedback of your own movements,

significantly improve the ability to accurately judge that action's goal when you see it in others.

The motor system update drives the social perception improvement.

Now, to move from just correlation to actual causation, we need studies that disrupt the system.

This is where the temporary lesion studies using transcranial magnetic stimulation or TMS are so vital.

These TMS studies provide that causal link.

They show the mirror network is necessary, not just active.

For instance, temporary lesions via repetitive TMS over the premotor cortex selectively impaired an observer's ability to perform proactive gaze.

And proactive gaze means looking not where the hand is, but predicting where the hand is going to be.

Exactly.

When the mirror system was temporarily knocked out with TMS, that ability to predict the target of the action just faltered.

The simulation, which you need for prediction, was temporarily disabled.

And they narrowed this down to specific body parts using a more precise technique, right?

Continuous theta burst stimulation or CTBS.

This was really refined work by Michael and others in 2014.

They showed this somatotopic necessity we talked about earlier.

They selectively applied CTBS over the brain regions for different body parts.

When they stimulated the hand area of the premotor cortex, participants got less accurate at identifying hand action goals.

And when they stimulated the lip area.

It impaired their ability to identify mouth action goals.

This proved that the mirror system isn't just incidentally active.

It's a necessary, causally organized architecture for identifying goals.

So if I temporarily disrupt the neural resources from moving my mouth, my ability to understand why you're pursing your lips diminishes.

It does.

And even our immediate physical state impacts this.

The sources show that people are significantly slower at predicting an observed actions target when they are physically restrained or unable to perform that action themselves.

The inability to reuse the motor plan acts as this measurable drag on their perception.

I think the perceptual after effect study is maybe the most visceral demonstration of this, of how your own motor history biases, how you see things.

It's a fantastic example of the bodily format shaping perception.

Participants were blindfolded and had to repeatedly perform a simple action like pushing an object away from them.

So they're building up this motor history of pushing.

Exactly.

Then when they watch videos of others performing actions that were ambiguous, could be a push, could be a pull.

Their recent motor experience induced a powerful perceptual after effect.

They were strongly biased to see the observed action as a push.

So my recent actions literally color my present visual perception of others.

Yes.

Your motor system creates this bodily formatted representation of pushing, and that representation is immediately reused, biasing how you interpret what you see.

And critically, when they delivered TMS over the premotor cortex,

that perceptual after effect completely vanished, which confirms that the mirror system is the causal link here.

It's the mediator.

It's responsible for integrating your own motor history into how you judge the goals of others.

OK, so this establishes ES as central to basic understanding.

But the authors are very careful to put boundaries on their theory.

They aren't claiming that ES explains every kind of action understanding.

That boundary is essential.

They see action understanding as a multilevel process.

ES is critically involved in goal description, identifying the immediate direct outcome of the action.

You are grasping the bottle.

Right.

But understanding the reasons for the action, the intentions, the beliefs, the desires behind it, that might be handled by a different system.

A separate, more cognitive, mind reading network.

Exactly.

A network typically associated with regions like the mesial frontal cortex and the temporal parietal junction.

So you have two systems, the fast, automatic, motor driven ES system that identifies the what and a slower network that deduces the why.

So a key question for future research is how those two systems talk to each other.

That's the frontier.

Does ES just feed its identified goal into the mind reading network?

Or is there a real two way interaction where, for instance, deducing someone's belief might then modulate or fine tune the motor simulation that's running in the background?

That's a fascinating question.

But the authors seem firm that goal identification based on the body is the indispensable building block for everything else.

It's the foundation.

OK, so moving to the broader social context, the theory posits that this bodily formatted reuse driven process is a foundational building block for social cognition.

And the strongest evidence for this comes from developmental studies with infants.

This research suggests that infants predict and interpret others actions by basically capitalizing on their own motor processes from a very early age.

Which makes perfect sense.

The capacity to understand an action is tied to the capacity to perform it.

That's the core finding.

Take the idea of motor repertoire constraint.

Researchers found that six month old infants were only sensitive to others action goals.

Meaning they could predict the outcome if those actions were already part of their existing motor repertoire.

So if the action was too complex for them to do themselves, their predictive ability just disappeared.

The motor system provides the lens through which they see the social world.

And they took this a step further with three month olds, demonstrating this amazing principle that experience precedes perception.

OK, what does that mean?

Typically, three month olds don't show sensitivity to others action goals, but the researchers motorically train them.

They use these sticky mittens that help the babies grasp things they couldn't otherwise.

After that motor training, the infants suddenly became sensitive to the goals of actions they saw others perform.

That is profound.

By boosting their motor repertoire, you immediately accelerate their social perception.

The internal bodily formatted representation gets built and the simulation system kicks on.

Absolutely.

And the ability to proactively gaze at the target of a grasping action strictly correlated with the infant's own grasping ability.

As their grasp matured, their predictive gaze matured.

The development of individual motor ability is intrinsically linked to the development of social understanding via E .S.

So E .S.

suggests that once the processes for doing an action are on board, the step to basic social cognition is just a matter of reuse.

It doesn't require some massive cognitive leap.

That's the parsimonious argument.

But the authors are careful to show that while E .S.

is foundational, it's not a lonely, solipsistic activity.

It can be profoundly modulated by social interactions, especially joint action.

Right.

When we're acting together, how does simulation work then?

Well, joint action is when two or more people collaborate on a shared goal think, like playing a piano duet or just passing an object back and forth.

Research on this suggests that individuals motorically represent not only their own part of the action, but also the other person's action, integrating both into a single collective whole.

So my system is running two motor programs at once, mine and yours, to make sure the collective goal happens smoothly.

Precisely.

Studies show that while there might be slight differences in mirroring when you compare individual versus joint tasks, the fundamental mechanism is still E .S.

It just requires refining the process to account for the shared goal.

The authors conclude that E .S.

reveals how deeply intertwined our own motor cognition and our social cognition really are.

So we've established the mechanics and the social necessity of E .S.

Now let's get into the most philosophical and, I think, personally resonant consequence, how E .S.

impacts our actual experience of the world.

Right.

The E .S.

account leads to two crucial consequences.

The first is what you can call the non -mentalistic rote to knowledge.

Because these bodily formatted representations let us identify and perceptually judge others' goals, we have a way of knowing what others are doing that is completely independent of accessing their complex mental states like beliefs or desires.

So I know you're grasping the water bottle because my motor system knows the physical goal of grasping to drink, not because I logically inferred that you must be thirsty.

Exactly.

And that's a powerful challenge to purely intellectualist models of social cognition.

And the second consequence, which you brought up right at the start, is this phenomenological link, the suggestion that observation and execution share a common experience.

The authors draw on the work of people like Mark Jenrod, who studied motor imagery.

Jenrod argued that imagining an action is so neurally close to actually doing it that the subjective experience of imagining must share a core phenomenal aspect with the experience of actually performing it.

And since action mirroring is also an instance of E .S., it's a reuse of that same system.

The conjecture is that observing an action must similarly share phenomenal aspects with performing it.

We feel something similar.

This suggests this idea of a shared manifold of intersubjectivity, where the boundaries between self and other are experientially porous thanks to our embodied system.

And the evidence for this shared experience is subtle, but it's really powerful.

Let's unpack the pianist study because it so vividly demonstrates how internal motor knowledge shapes external perception.

This involved expert pianists versus non -experts.

They either performed a key sequence on a piano or just watched someone else perform it.

And the sequence produced this ambiguous tone pair.

A sound that could be heard is either rising or falling in pitch.

OK, so an auditory illusion.

Exactly.

And this is where the motor system intervened.

For the expert pianists only, the physical direction of the key presses significantly influenced how they perceive the pitch,

regardless of whether they were the ones performing the action or simply observing it.

That is astonishing.

So my years of physical piano training, my bodily format literally biases how I hear an external sound.

And that bias holds even when I'm just passively watching someone else.

It demonstrates that the motor representation is not just passively registering information.

It's an active filter, an interpreter of sensory information, and it's equally effective in execution and observation.

But the most striking evidence connecting the bodily format to experience has to be the study with aplasic individuals, those born without hands and phantom limbs.

This takes embodiment to its absolute limit.

This is a profound study.

It decouples the physical body from the internal bodily representation.

They had congenitally aplasic individuals, some of whom experienced a phantom limb and some who did not.

They were shown pictures of a rotating hand.

The hand could rotate through a short path, which is biomechanically impossible, or a longer path, which is plausible.

You'd think if you don't have hands, the simulation would just fail.

That's what a purely visual, non -embodied model would predict.

But the results were dictated by the internal format.

The individuals who experienced a phantom limb.

So they had an internal motor representation of a hand, even without the physical hand.

They saw the plausible rotation.

Yes.

They reported observing the hand moving along the longer, biomechanically plausible path.

Their phantom limb provided the internal motor structure, the bodily formatted representation that was necessary to run the simulation.

And that simulation imposed the rules of biomechanics on their visual experience.

Exactly.

The other aplasic individuals, the ones who lacked that phantom limb representation, only saw the shorter, impossible path.

Without the bodily format, the simulation couldn't run to constrain what they saw.

So the internal bodily representation is the crucial factor, not the physical limb itself.

It can exist and operate even in the absence of the body part it represents.

Which suggests that what we experience when others act is similar to what we experience when we act.

And that shared phenomenal element is rooted in the structure of our motor system.

So this brings us to the final really provocative distinction the authors make about action experience.

There's a conservative view and a more radical one.

The conservative view is that action experiences are just experiences of bodily configurations or sensory effects.

There's nothing fundamentally motor about the phenomenology itself.

But the preferred view is much more ambitious.

It is.

The radical view posits that some actions can be experientially present in a way that's similar to how physical objects are.

They draw an analogy to object indexes, which let us maintain a continuous experience of an object, even when it's temporarily hidden from view.

So, yes, using its bodily format allows us to experience the goal directed action itself, the grasping to eat as a unified perceptual whole, not just a collection of parts like fingers closing.

Precisely.

And if this radical view is correct, yes, doesn't just inform us about the action.

It enables a distinct characteristic phenomenology of action experience.

It provides this profound, immediate, non inferential connection to other people.

This is the essence of embodied resonance.

That was a tremendous deep dive.

I mean, covering everything from single cell recordings and monkeys to the philosophical nature of consciousness.

It's really hard to overstate the importance of that reuse principle in this framework to summarize their main contribution.

Embodied simulation, or yes, is fundamentally driven by the reuse principle and defined by bodily formatted representations, not resemblance.

This mechanism, based on the mirror neuron system, provides an empirically supported non -mentalistic pathway for identifying others action goals.

And this action identification is the foundational building block of basic social cognition, and it strongly suggests a common phenomenal ground between the person doing and the person watching.

It does.

And if we think about the frontier of this research, the biggest question is still proving that phenomenology.

The authors explicitly hope that future research will really investigate whether E .S.

truly involves a characteristic phenomenology of action experience.

They want to know if E .S.

lets us actually experience the action itself when we observe others, a kind of shared sensation that goes way beyond just visual input.

Are we really feeling the constraint, the goal, the motor intention?

That's the question.

So think about that.

The next time you watch someone execute a precise, practiced movement like a musician hitting a difficult chord or a craft person making a delicate carving motion, are you just seeing them?

Or are you briefly, internally sharing the feeling, the goal and the biomechanical structure of that action?

Are you experiencing embodied resonance?

That shared feeling, that common ground between yourself and someone else is what these authors suggest might be the default setting of the human brain.

Thank you so much for joining us for this deep dive into embodied resonance.

We hope you feel thoroughly informed and ready to explore your own action experiences.