Neuralink, Elon Musk's brain chip company recently pushed
back on claims that it violated animal welfare laws a few years ago while
testing on monkeys. This year the company plans to test on human subjects but
when it does? what would this major step mean for brain implant science?
Academics have conducted clinical trials in people with
brain implants. for about 20 years now academic research brain implants up
until this point more or less have almost exclusively been with wires.
The difference that the n1 has the neural. It is fully implantable,
it is battery powered, it is wireless. All of this is being done over bluetooth
protocol.
let's dive into the science behind Neuralink to understand
how exactly human brain chips work?
The science behind how these implants work is not that
different from how you would go about trying to measure the energy from a
double A battery. It's the same principle that we're doing with these brain
implants this is called neuroelectrophysiological recording.
When you move your arm to the right, certain sets of neurons
are activated in a certain pattern. Listening in to that activity and that
pattern you can predict very quickly which direction the arm is going to move.
These are the neurons that are directly wired to your muscle.
Unless that pathway from the brain to the spinal cord to the muscle is damaged, the way it is in patients with paralysis. If that pathway is damaged then the neural signals from the brain aren't going to get down to move the muscles, but in many cases the signals are still present in the brain they're just not getting out. So if you reach in and put something that listens in to those neurons and you know what's happening to the muscle. That's the goal of a brain implant.
These new developments at Neuralink are a culmination of
breakthroughs by brain machine interface researchers, especially in the last
few decades. For example in 2002 the first demonstration of real-time cursor
control in monkeys took place. In 2008 a monkey controlling a robotic arm in
three dimensions fed itself. In 2012 the first brain-controlled robotic arm by
a human. In 2017 a human controlled a cursor mentally to type out words and sentences.
In 2018 where a human subject mentally controlled a tablet
to do things like browse the web send emails and play games or music. All
that's been done with a couple hundred elelectrodes.
But in 2019, Neuralink a private company changed the game
when it unveiled a pig named Gertrude with a wireless implant that monitored
about a thousand neurons. The neurons are like wiring and you kind of need an
electronic thing to solve an electronic problem. That was a very interesting
moment because it signaled to the community that they're serious, they're
investing, they're building hardware from scratch and they're putting it in large
animals.
For the pig, the electrodes were implanted in somatosensory
cortex allowing them to measure sensory activity like that of taking a step
every time.
In April of 2021, Neuralink released the so-called mind pong
video. Pager was the name, it's a rhesus macaque which is you know the type of
monkey that is very commonly used in this field. It is implanted with two of
the n1 devices, the neural link devices performing brain control of cursor
onscreen. That's extremely significant because here neurolink is showing their
new hardware, their new device in their hands works in a monkey. That's the
level that's necessary to convince the scientific community, to convince the FDA
. The n1 device in pager was eye opening because of the sheer number of individual
electrodes that had been implanted. There was definitely a lot of clever
engineering that went in to that to build a device that can transmit 2048
electrodes worth of spiking information right of digital ones and zeros of
spikes over a radio wirelessly and when you have that many channels, the
performance that you should be able to get should eclipse.
How does a device like the n1 get implanted in a subject's brain
without make no mistake? This is neurosurgery, it is not a joke. This requires
cutting the skin, getting down to skull drilling a hole in the skull, exposing
what's called the dura, which is this protective layer of tissue that surrounds
the brain cutting. The dura folding it back to expose the brain and then you
get to the surface of the brain where you can implant the electrodes.
The biggest risks with these types of techniques are
infection bleeding and tissue damage, so what would it take for the fda to
approve clinical trials in humans. The neurolink device are called class 3
medical devices, they are implantable and they're going into very sensitive
body cavities that is the highest level of scrutiny.
If the fda says yes then their clinical trial is approved
and neurolink can enroll and recruit human participants.
This type of technology has the potential to transform our
treatments not just for stroke and paralysis and degenerative disease, motor
degenerative diseases but also for pretty much every other type of brain
disease from parkinson's to epilepsy to dementias alzheimer's and even
psychiatric disease seeing neuralink and the other companies in this space
start an industry around neuroengineering brain machine interfaces. Neuroprosthetics has been a tremendous amount
of validation for neuroscientists and engineers who have been working in this
space for decades.
References : All data is provided by Neuralink
