Brain Awareness Video Contest

How Neurons Work

  • Published26 Feb 2024
  • Source BrainFacts/SfN

Neurons, or tiny cells in our brains, constantly send messages to each other. But how do they do it? Professor Amelie and Professor Rosie explain how these cells communicate inside our brains.

This is a video from the 2023 Brain Awareness Video Contest.

Created by Curtis Neveu.




I'm Professor Amelie! And I'm Professor Rosie. We're going to tell you how neurons work. What's a neuron? That's a super great question, Rosie. A neuron is something very, very tiny inside your brain. It's so small that you can't even see it. That's right. And they help you think.

Here are three neurons: neuron one, neuron two, and neuron three. Let's see these neurons in action. Neuron one is activated. Then, neuron one sends a signal to neuron two by activating a synapse. What’s a synapse? Another great question. Each one of these connections is a synapse.

Let's take a closer look. There's a presynaptic side that comes from an axon and a post-synaptic side attached to the dendrite. When the presynaptic side is activated, it then activates the post-synaptic side. The activation then travels down the dendrite to the soma. This is the center of the cell. Then, to the axon. That's where the action potential is made. Yep!Would you like to see an action potential? Yeah! Let's go! Woo-hoo! Woo-hoo!

Here we are! Let's take a look around. We're standing on the axon. The signal travels down the dendrite, then it goes to the soma. That’s a big ball over there. Yep! And then activates the action potential in the axon. Let’s go in slow motion. I’m going in slow motion. [Laughing].

Check this out. These are channels that open when the action potential comes by. This green one opens when the action potential arrives. It lets in an ion, then it closes. After that, the blue channel opens, and it lets out an ion. Isn’t that cool, Rosie? I’m still in slow motion. Oh yeah, sorry. Whew! I was stuck in slow motion. Okay, let's get out of here.

Okay, so now, the action potential travels down the axon, and now it activates the synapse. And then activates neuron three. So, neuron one gets activated, it activates a synapse and activates a dendrite, and travels down the dendrite to the soma. Then, an action potential is activated. This travels down the axon to another synapse, which activates neuron three.

That’s really cool. Wow! Great job, Rosie. Bye bye! See you next time!


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