Listen to this.

(static)

That is the sound of neurons firing inside your brain.

And it's the key to controlling machines with our thoughts.

(upbeat music)

A brain computer interface, also known as a

brain machine interface, is a system that allows

direct communication between an organism's brain

and an external machine.

Because our brain's neurons communicate via electrical

impulses, we can listen into these signals

and decode them for our use.

Dr. Miguel Nicolelis is at the forefront of developing

BCI technology.

By studying and monitoring the electrical signals of

the human brain, his lab was able to create

mind-controlled exoskeletons that translate the thoughts

of paraplegic humans via an EEG cap

into physical movement through the exoskeleton.

Brainstorms are a way to collect electrical signals

produced by large number of brain cells.

We're able to demonstrate that we could read these

brainstorms on rat and monkey brains and

decode some simple motor messages that were embedded

in these brainstorms and use them to allow these animals

to voluntarily control the movements of devices

just by thinking.

The most cutting edge brain computer interfaces

require direct implants into the brain.

Dr. Nicolelis works with monkeys who have moved via

these advanced implants everything from virtual avatars

of themselves on computer screens,

to a robot across the world in Kyoto, Japan.

In this experiment, the monkey is using the scooter

to reach the food bowl.

It only has to think about moving,

and the cart does the rest.

The robotic scooter becomes a mechanical extension

of the monkey and it knows that it doesn't need to move

physically in order to reach the bowl.

And that evolved very quickly, we were able to show

that we could record the same brainstorms from human

patients and as that evolved, we saw that technology

could become the core of a new approach to treat patients

who suffer from devastating levels of paraparalysis.

The work being done at Dr. Nicolelisis' lab

shows us that brain computer interfaces can successfully

read and execute our thoughts.

Whether they are implanted or worn,

today other neuroscientists working with brain implants

are also discovering how to tune into parts of the brain

related to the senses of touch, smell and even sight.

[Miguel] The brain is the most complex biological device

that we know in the universe.

The moment we understand it, we understand everything.

The brain is just stardust combined into this amazing

mesh of billions of cells interconnected producing

a version of reality.

In the near future, this technology will enable

amputees to plug directly into their prostheses

and allow spinal cord injury victims

to move again.

It's going to be a while before we map out the entire

human brain because some say our brains are made up of

about as many neurons as there are stars in the entire

Milky Way Galaxy.

But in the words of Dr. Nicolelis,

Once you get the brain outside the physical limits of

the body, the limit is the imagination.

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