Chapter 10: Planning and Executing Actions

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Welcome back everybody, ready to dive into another fascinating topic.

Today we're taking a deep dive into how our brains plan and execute actions.

And it's more complex than you might think.

Oh, definitely.

I mean, we do it every day without even a second thought, but there's a whole symphony of brain regions working together behind the scenes.

It really is remarkable.

So where should we start?

Well, this chapter actually tackles some pretty big questions about free will and consciousness.

Oh, hold on.

Yeah.

Let's maybe back up a bit before we get into those existential depths.

You got it.

How about we start with the basics, like the difference between those automatic actions we do without thinking like pulling your hand away from a hot stove and those more deliberate goal oriented actions.

Okay.

So like a reflex versus deciding to make a cup of coffee.

Exactly.

Perfect example.

Yeah.

Those reflexes are mostly handled by the spinal cord while goal oriented actions involve a whole network of brain regions with the frontal lobe as the star of the show.

Okay.

So tell me about this frontal lobe superstar.

Well, you can think of it as the executive control center of your brain.

So like the CEO.

Exactly.

And within the frontal lobe, there's a hierarchy of areas each responsible for different aspects of action planning and execution.

Okay.

A hierarchy.

So it's like a chain of command.

Precisely.

At the top, we have the prefrontal cortex, the ultimate strategist setting goals, making plans and decisions.

So the prefrontal cortex is the big picture guy.

Got it.

What happens next?

From there, the plan gets passed down to the premotor cortex, which figures out the specifics like the step -by -step instructions for achieving that goal.

So if my goal is to make that cup of coffee, my prefrontal cortex says, let's do this.

And then the premotor cortex is like, okay, first grab the mug, then the coffee.

Exactly.

Breaking it down into manageable chunks.

Love it.

And the premotor cortex also uses sensory feedback to guide your movements.

So making sure you don't spill the coffee or walk into a wall on the way to the kitchen.

Exactly.

It's constantly adjusting based on the information it's receiving.

This is already making me think about how much we take these processes for granted.

Absolutely.

And then we have the supplementary motor area, which is all about those smooth practice movements, the things you do without even thinking about it.

Like riding a bike or typing on a keyboard.

Exactly.

Think about learning to write your name as a child.

At first, it took so much concentration, but now you can do it effortlessly.

Wow.

It's incredible how our brains can automate these complex skills.

It really is.

Okay.

So we've got the prefrontal cortex setting goals, the premotor cortex mapping out the steps and the supplementary motor area smoothing out the execution.

What a team.

A well -oiled machine.

But to keep this machine running smoothly, we need another key player, working memory.

Ah, yes.

Working memory.

Our brain's temporary storage system.

It's like our mental juggling act, try to keep all those balls in the air.

That's a great analogy.

It does have a limited capacity though, which is why you might forget what you were going to say if someone interrupts you or why multitasking can be so challenging.

Yeah.

Ever try remembering a phone number while also trying to cook dinner?

It's a recipe for disaster.

Exactly.

Distractions and information overlay can really tax our working memory.

So which part of the brain is responsible for this juggling act?

Well, it's actually a team effort.

The prefrontal cortex is the main juggler holding onto those bits of information, but it gets help from the hippocampus, which adds long -term memories to the mix, and the amygdala, which flags information based on its emotional significance.

So if I'm trying to remember that grocery list while also having a conversation and sitting on my phone rings, it's no wonder I might forget the milk.

Exactly.

Our brains are constantly bombarded with information and sometimes things slip through the cracks.

It's like a mental traffic jam.

Yeah, you could say that.

But even with those limitations, our brains are incredibly flexible and adaptable.

That's reassuring.

Okay, so we've got goals plans, smooth movements, and working memory.

What else is involved in this dance of action?

Well, now we need to introduce the basal ganglia.

The basal ganglia.

What are they all about?

Think of them as the action gatekeepers of the brain.

They help us select which action to perform and when to switch between different goals.

Okay, action gatekeepers.

So like bouncers at a club.

Kind of.

Imagine you have multiple goals competing for your attention.

You're thirsty, but you also need to finish that email and oh, there's that itch you need to scratch.

Oh yeah, I can relate to that.

The basal ganglia help you prioritize and switch between those goals, making sure you don't get stuck in a loop of endless scratching while your inbox overflows.

So they're involved in both simple actions like scratching an itch and more complex behaviors like managing multiple tasks.

Precisely.

And they're also essential for things like learning new habits and developing automatic responses.

That's fascinating.

So they're like the ultimate multitaskers.

Well, not quite.

Multitasking is a bit of a myth.

Our brains are actually much better at switching quickly between tasks rather than doing multiple things simultaneously.

Oh, so that's why I can never seem to actually get anything done when I try to juggle too many things at once.

Exactly.

There's always a cost to switching back and forth between tasks, even if it happens very quickly.

That makes a lot of sense.

It's like our brains are time sharing rather than multitasking.

That's a great way to put it.

And it highlights the incredible efficiency and flexibility of our brains.

Absolutely.

And speaking of efficiency, we can't forget about the cerebellum.

Ah, yes.

The cerebellum, often referred to as the maestro of movement.

I remember reading about its role in coordination and balance,

but tell me more about what it does.

It's much more than just a supporting player.

The cerebellum receives input from your senses and the cortex, constantly comparing what you intended to do with what you actually did and making tiny adjustments to improve your performance.

So it's like a constant feedback loop refining our movements.

Exactly.

Think about learning to play tennis or dance.

The cerebellum is what helps you refine your timing balance and coordination, eventually making those movements feel smooth and effortless.

Wow.

It's amazing how much is going on behind the scenes to make even the simplest actions possible.

It really is a marvel of neural engineering.

Okay.

So we've covered a lot of ground here.

The frontal lobes, hierarchy working memory, the basal ganglia as action gatekeepers, and the cerebellum fine tuning our movements.

It's incredible how all of these brain regions work together to orchestrate even the simplest actions.

And we're just getting started.

This chapter also delves into some groundbreaking research that challenges our understanding of free will and introduces us to some incredibly intriguing types of neurons, like mirror neurons and voneconomo neurons.

I've heard they're involved in imitation and empathy.

They are, and they're one of the most exciting discoveries in neuroscience in recent decades.

They fire both when we perform an action and when we observe someone else doing the same action, suggesting a neural basis for our ability to understand and learn from others.

Wow.

It's like our brains are wired for connection.

But before we dive into those fascinating mirror neurons, let's take a closer look at this idea of free will.

Because if our brains are already initiating actions before we're even consciously aware of them, as that libette experiment suggests, what does that say about our control over our choices?

That's the million dollar question, isn't it?

And it's one we'll be exploring in depth as we continue our deep dive.

Okay.

So let's talk about free will.

You mentioned the libette experiment where they found that brain activity related to an action happens before a person is even aware of making the decision to act.

It's like our brains are making choices without us.

It's definitely a head scratcher and it raises some big questions about how much control we really have over our actions.

Right.

Like are we really calling the shots or are we just along for the ride?

Exactly.

Some argue that our conscious experience of decision -making might just be a story we tell ourselves after the fact.

So like we think we're making the choice, but it's actually already been subconscious.

That's one interpretation,

but there are other ways to look at it.

Oh,

tell me more.

Well, some researchers propose that we still have a veto point, a brief window of time where our conscious mind can step in and say, nope, changing my mind.

Okay.

So it's like a last minute override.

Our conscious mind can hit the brakes.

Exactly.

Think about it like this.

You're walking down the street and you see a big slice of chocolate cake in a bakery window.

Okay.

Your brain might automatically trigger the urge to go in and buy it, but then your conscious mind can step in and be like, wait a minute, I'm trying to cut back on sugar and redirect your actions.

Okay.

That makes me feel a little better about having some agency in my choices, but this whole discussion is definitely a mind bender.

It really is.

It challenges our assumptions about what it means to be human and make choices.

It does, but I guess that's what makes it so fascinating.

Let's shift gears a bit and talk about those mirror neurons you mentioned earlier.

What exactly are they and why are they so special?

So mirror neurons were first discovered in monkeys back in the nineties.

And what's so cool about them is that they fire both when a monkey does something like grab a peanut and when it watches another monkey or even a human doing the same thing.

So it's like their brines are mimicking the action they're observing.

Precisely.

And this has led to some really interesting theories about the role of

in understanding the actions and intentions of others.

Oh, how so?

Well, imagine you see someone reach for a glass of water.

Okay.

Because your mirror neurons fire as if you were reaching for the glass yourself.

It allows you to quickly understand that person's intention.

They're thirsty and they want to take a drink.

Wow.

So it's like our brains are putting ourselves in the other person's shoes.

Exactly.

And this might be a key part of how we learn new skills by observing others and even how we develop empathy.

That makes sense.

It's like when you see someone stub their toe and you wince in pain, even though it's not your toe that got hurt.

Exactly.

It's like our mirror neurons are allowing us to experience the world through the eyes of others.

That's incredible.

It's like our brains are wired for connection.

It is.

And it shows how our understanding of others is deeply rooted in our own bodily experiences.

Wow, this is all so mind -boggling.

And we haven't even talked about those other mysterious neurons you mentioned, the Von Economo neurons.

Yes, the Von Economo neurons.

These are truly unique cells.

They're much larger than typical neurons and have a distinct shape with fewer branches.

So what does that mean for their function?

That's the big mystery.

We know they're found in very few species, primarily those with large brains like humans, great apes, whales, and elephants.

So species known for their intelligence and complex social behaviors.

Exactly.

And because of their unique structure and long -range connections throughout the brain, some scientists think Von Economo neurons might play a role in rapid communication across different brain areas.

Like a high -speed neural network.

You could say that.

They might be involved in those aha moments of insight or in processing complex social information quickly.

That's amazing.

And a little humbling to think about how much we still don't know about these incredible cells.

Absolutely.

But that's part of what makes neuroscience so exciting.

It's a field of constant discovery.

So true.

Now, as fascinating as healthy brain processes are, this chapter also takes a look at what happens when things go wrong.

You're right.

And studying these disorders can give us valuable insights into how the brain normally works.

It's like trying to figure out how a car works by taking apart a broken engine.

Exactly.

And the chapter covers a range of motor disorders from myasthenia gravis where communication between nerves and muscles is disrupted to spinal cord injuries which highlight the crucial role the spinal cord plays in movement.

Right.

And damage to the spinal cord can really impact a person's ability to move and interact with the world.

It can.

But perhaps the most intriguing disorders discussed in this chapter are those that involve the basal ganglia given their crucial role in selecting and initiating actions.

Okay.

So tell me more about those disorders.

You mentioned Parkinson's disease and Huntington's disease, both of which involve the basal ganglia, but in different ways, right?

Right.

Both involve degeneration in the basal ganglia, but in different areas, which leads to very different symptoms.

In Parkinson's disease, there's a loss of dopamine producing cells in a region called the substantia nigra.

And dopamine is a neurotransmitter that's important for movement, right?

Exactly.

And without enough dopamine, the delicate balance of

basal ganglia gets disrupted, leading to those classic Parkinson's symptoms like tremors, rigidity, and difficulty initiating movements.

I know that L -Dopa is a common treatment for Parkinson's.

How does that work?

L -Dopa is a precursor to dopamine.

So basically, it can be converted into dopamine in the brain.

It helps to alleviate some of the motor symptoms, but it's not a cure.

And long -term use can lead to side effects.

That's where deep brain stimulation comes in, right?

I've heard it can be really effective.

It can be.

It involves implanting electrodes in specific areas of the brain, typically in the subclamic nucleus, which is part of the basal ganglia circuitry.

So what do those electrodes do?

They deliver continuous electrical pulses that help to regulate the activity of the basal ganglia.

It's like resetting the brain's electrical circuits.

Kind of.

It's still not fully understood why it works so well, but it seems to help restore some of the balance that's lost in Parkinson's disease.

That's incredible.

What about Huntington's disease?

How is that different from Parkinson's?

Well, Huntington's disease is a genetic disorder that causes degeneration in a different part of the basal ganglia, the striatum.

What does that lead to?

This degeneration leads to uncontrolled jerky movements, often described as a dance, as well as cognitive and psychiatric symptoms.

So unlike Parkinson's, where there's difficulty starting movements, Huntington's is more about a lack of control over movements.

Exactly.

The basal ganglia are no longer able to properly filter and select actions, which results in those involuntary movements.

And is there a treatment for Huntington's disease?

Unfortunately, there's no cure yet,

but research is ongoing.

It's amazing how much we've learned about these disorders, but also sobering to realize how much more there is to discover.

You're right.

And it highlights the importance of continued research to better understand and treat these conditions.

Absolutely.

Okay.

So we've covered a lot in this deep dive, from the basic mechanisms of action planning and execution to those mind -bending questions about free will and the fascinating world of mirror neurons and von Economo neurons.

And we even explored the complexities of motor disorders.

It's a testament to the incredible power and complexity of the human brain.

It really is.

And it makes you appreciate how much we take for granted.

I agree.

Even a simple action like picking up a cup of coffee involves a symphony of neural activity.

And speaking of coffee.

Yeah.

I think I need another cup after all that brain bending discussion.

You know, it's amazing to think about all the different brain regions involved in even the simplest actions.

Right.

Like even just reaching for that cup of coffee, it's a whole coordinated effort.

Seriously.

And we haven't even touched on everything this chapter covers.

No, not even close.

There's so much more to explore.

Like those strange new neurons we talked about, the von Economo neurons.

What other mysteries are hidden in our brains?

It makes you wonder what future research will uncover.

Right.

It feels like we're just scratching the surface.

It really does.

There's still so much we don't know about how the brain works.

It's kind of humbling.

Absolutely.

But it's also what makes neuroscience so fascinating.

There's always something new to learn.

I agree.

So out of everything we've talked about, what stands out to you as the most important takeaway from this deep dive?

That's a tough one.

But I think for me, it's the realization that even the simplest actions we perform involve this incredibly intricate interplay of multiple brain regions.

It's like a symphony of neural activity.

Exactly.

And when you think about it, it's truly remarkable how seamlessly it all works together.

It really is.

But it also highlights the potential consequences when something goes wrong in this delicate system.

Yeah, we saw that with Parkinson's and Huntington's diseases.

Exactly.

Even small disruptions in these neural pathways can have a huge impact on a person's life.

It's a good reminder to take care of our brains.

Definitely.

And to support research aimed at understanding and treating these conditions.

Well, I think that's a perfect note to end on.

I agree.

It's been another fascinating deep dive into the world of neuroscience.

Always a pleasure.

And to all our listeners out there, remember, the brain is a complex and amazing organ, and there's still so much we don't know about it.

So keep those minds curious and never stop exploring.

Until next time.