Neurons
Neuron
Structure
The neuron
That looks weird.... What is it?
A neuron!
It's a kind of cell
What does it do? Why is it so long?
They transmit messages over long distances. So, they need to be long
The neuron
Cool!
How does it do all that?
Well, there are a couple really important parts to a neuron
Wait! Let me get my notebook
The neuron
Let's start with this big, kinda round part over here
This is the cell body. This is the body of the neuron where all the normal cell-things happen...
...making proteins, replicating DNA, packaging waste, etc.
The neuron
What are these branch-y thingies sticking out from it?
These are dendrites! This is where our neuron can receive signals from other neurons
Each dendrite is connected to another neuron.
What was that??!
That was an action potential! It's the messages that neurons carry
CooOool...
The neuron
Does this long part have a name?
That's the axon!
It carries messages away to new cells
You got it!
Then the message gets passed to the dendrites of other neurons
So, messages come in through the...
dendrites, and then get passed down the axon?
Okay, I think I get one neuron... but how does it communicate to the next one?
How does a signal get from one neuron to the next?
This is the best part!
The synapse
It's a tiny gap between two neurons.
To get the signal across the gap, it uses tiny molecules called neurotransmitters.
Ok, so how does a neuron "know" when and what to communicate?
Let's look at a whole signaling response to try to understand that...
It starts with a signal coming in from the outside world...
This diagram shows the pain signal coming in through the finger.
A sensory neuron in the finger sends the signal up the arm, up the spinal cord, and into the brain
Is it called a "sensory neuron" because it senses information from the outside world?
You're so smart!
Once the signal reaches the brain, a number of interneurons figure out what to do with it.
...but if it's too hot, let me guess...
If it's just a nice warmth, they might decide the hand should stay...
they'll send a message to the "moving neurons" to pull back?
You're almost right...
except they're called Motor Neurons
Alright, let me try this...
The sensory neurons sense things going on outside the body.
Then they send those signals to the interneurons in the brain (and spinal cord)...
Then, those interneurons send a signal out to the motor neurons about what to do...
...but then what happens?
Those motor neurons send their signals to muscles, telling them what to do!
It looks something like this
Sense the environment...
Figure out what to do about it...
and then take action!
Alright, now here's the real big question
The brain does all our thinking and learning...
and it's just made of neurons...
how does understanding neurons help us understand learning?
Hmmm... a big question indeed!
a small part of the answer has to do with a thing called plasticity
plastic- itty...?
It's more like "pla-sti- city"
It sounds fancy, but saying something is 'plastic' just means it can be molded and changed
Okay, so... ...
Pretty much!
Oh! Neurons can change, and that is what leads to learning?
More specifically, it's those synapses that are changing.
The connections get stronger with each use
Flash cards...
...MmmHmmm
worksheets...
swim practice...
even...
quizzes and tests.
So, it's all to use the plasticity of the brain to make stronger synapses?
Isn't learning great?!
Neurons
By mrgliddon
