Episode 14 – Neat Nerves

How does the nervous system work?

hallux-leaningHello again medical chums and welcome to my blog post about building my very own human body.

Today Nurse Nanobot and I installed our body’s nervous system.

Press the play button above to listen to us explore your brain and also read loads of interesting facts below!

Nervous System

The brain might be in charge of giving out the orders but it couldn’t carry them out without the help of the nervous system.

It’s like a complicated network of train tracks all over the body.  And it’s a track that goes both ways – it also takes messages from across your body and delivers them into the brain.

It’s made up of two main parts; the central nervous system and the peripheral nervous system.

Central Nervous System

The central nervous system is made up of the brain, spinal column, and the retina. Their job is to process what’s going on in the body and issue orders.

They’re kept safe within the tough bones of the skull and spine.  They need to be well protected, without them you’d not be able to move or feel anything.

Peripheral Nervous System

The peripheral nervous system comprises the nerves that extend from your spine all the way to the tips of your fingers and all around every organ.

You have five senses – remember what they are?  Touch, taste, sight, hearing and smell.  The peripheral nervous system carries the messages from the outside world to the central nervous system for processing.

Neurons

All your nerves – those tiny wires and cables – are actually mostly made up of neurons. These are microscopic cells that have branches that allow them to connect to other neurons with synapses as the connecting glue.  And there are a hundred billion of them in your nervous system!

The glial cells support the neurons and keep them healthy, taking away debris and protecting them with a coating of a substance called myelin – like the plastic coating of electrical wires.

There are two main types of neurons:

  • Sensory neurons take information in about the world about you in response to touch, sound, taste smell and light and send it to the brain.
  • Motor neurons go the other way and take signals from the brain and spinal cord to make muscles contract to make things move.

Nurse Nanobot’s Orrible Old Anatomy Fact

nanobot

Those snappy synapses and nervy neurons are powered by electricity and if you could harness all the electricity in your body right now there would be enough to power a torch!

And what is even more weird is that if you attached a battery to a severed finger you could make it twitch!

Less gruesomely, electricity is harnessed by doctors to help people when signals from their own motor neurons aren’t getting through.

For example, pacemakers are tiny machines that give small electric pulses and are implanted near the heart to help it beat regularly.

hallux-bodyparts

Disgusting Details

Have you ever stood up and your foot feels like a horrible wobbly jelly?  It can be hard to walk!

Or if you’ve slept on your arm it can feel like it belongs to someone else and that can be REALLY creepy!

It’s nothing to be scared of. All that has happened is that the vessels delivering oxygen-rich blood to the nerves in that area have been temporarily squashed, making the nerves go to sleep and cutting off the connection to the brain. It’s like when you’re on the internet and the connection breaks, and everyone knows how annoying that can be!

And it can feel even weirder when the sensations return – sometimes you get pins and needles, which is a prickly tingly feeling of everything getting back to normal.

That’s it for today.  Join me and Nurse Nanobot on our next blog, where we will tell you what happened when we added the control centre of the whole body – the brain no less.

See you next time for more medical mayhem!

> Visit the Professor Hallux Builds a Body Homepage
> Download the free Builds a Body podcast from iTunes