How well become cyborgs and extend human potential Hugh Herr
I’m an MIT professor,
but I do not design buildings
or computer systems.
Rather, I build body parts,
bionic legs that augment
human walking and running.
In 1982, I was in
a mountain-climbing accident,
and both of my legs had to be amputated
due to tissue damage from frostbite.
Here, you can see my legs:
24 sensors, six microprocessors
and muscle-tendon-like actuators.
I’m basically a bunch of nuts and bolts
from the knee down.
But with this advanced bionic technology,
I can skip, dance and run.
(Applause)
Thank you.
(Applause)
I’m a bionic man,
but I’m not yet a cyborg.
When I think about moving my legs,
neural signals from
my central nervous system
pass through my nerves
and activate muscles
within my residual limbs.
Artificial electrodes sense these signals,
and small computers in the bionic limb
decode my nerve pulses
into my intended movement patterns.
Stated simply,
when I think about moving,
that command is communicated
to the synthetic part of my body.
However, those computers can’t input
information into my nervous system.
When I touch and move my synthetic limbs,
I do not experience normal
touch and movement sensations.
If I were a cyborg and could feel my legs
via small computers inputting information
into my nervous system,
it would fundamentally change, I believe,
my relationship to my synthetic body.
Today, I can’t feel my legs,
and because of that,
my legs are separate tools
from my mind and my body.
They’re not part of me.
I believe that if I were a cyborg
and could feel my legs,
they would become
part of me, part of self.
At MIT, we’re thinking about
NeuroEmbodied Design.
In this design process,
the designer designs human flesh and bone,
the biological body itself,
along with synthetics to enhance
the bidirectional communication
between the nervous system
and the built world.
NeuroEmbodied Design is a methodology
to create cyborg function.
In this design process,
designers contemplate a future
in which technology
no longer compromises separate,
lifeless tools from
our minds and our bodies,
a future in which technology
has been carefully integrated
within our nature,
a world in which
what is biological and what is not,
what is human and what is not,
what is nature and what is not
will be forever blurred.
That future will provide
humanity new bodies.
NeuroEmbodied Design
will extend our nervous systems
into the synthetic world,
and the synthetic world into us,
fundamentally changing who we are.
By designing the biological body
to better communicate
with the built design world,
humanity will end disability
in this 21st century
and establish the scientific
and technological basis
for human augmentation,
extending human capability
beyond innate, physiological levels,
cognitively, emotionally and physically.
There are many ways
in which to build new bodies across scale,
from the biomolecular
to the scale of tissues and organs.
Today, I want to talk about
one area of NeuroEmbodied Design,
in which the body’s tissues
are manipulated and sculpted
using surgical and regenerative processes.
The current amputation paradigm
hasn’t changed fundamentally
since the US Civil War
and has grown obsolete
in light of dramatic advancements
in actuators, control systems
and neural interfacing technologies.
A major deficiency is the lack
of dynamic muscle interactions
for control and proprioception.
What is proprioception?
When you flex your ankle,
muscles in the front of your leg contract,
simultaneously stretching muscles
in the back of your leg.
The opposite happens
when you extend your ankle.
Here, muscles in the back
of your leg contract,
stretching muscles in the front.
When these muscles flex and extend,
biological sensors
within the muscle tendons
send information
through nerves to the brain.
This is how we’re able to feel
where our feet are
without seeing them with our eyes.
The current amputation paradigm
breaks these dynamic muscle relationships,
and in so doing eliminates
normal proprioceptive sensations.
Consequently, a standard artificial limb
cannot feed back information
into the nervous system
about where the prosthesis is in space.
The patient therefore
cannot sense and feel
the positions and movements
of the prosthetic joint
without seeing it with their eyes.
My legs were amputated
using this Civil War-era methodology.
I can feel my feet,
I can feel them right now
as a phantom awareness.
But when I try to move them, I cannot.
It feels like they’re stuck
inside rigid ski boots.
To solve these problems,
at MIT, we invented the agonist-antagonist
myoneural interface,
or AMI, for short.
The AMI is a method to connect nerves
within the residuum
to an external, bionic prosthesis.
How is the AMI designed,
and how does it work?
The AMI comprises two muscles
that are surgically connected,
an agonist linked to an antagonist.
When the agonist contracts
upon electrical activation,
it stretches the antagonist.
This muscle dynamic interaction
causes biological sensors
within the muscle tendon
to send information through the nerve
to the central nervous system,
relating information on the muscle
tendon’s length, speed and force.
This is how muscle tendon
proprioception works,
and it’s the primary way we, as humans,
can feel and sense the positions,
movements and forces on our limbs.
When a limb is amputated,
the surgeon connects these opposing
muscles within the residuum
to create an AMI.
Now, multiple AMI
constructs can be created
for the control and sensation
of multiple prosthetic joints.
Artificial electrodes are then placed
on each AMI muscle,
and small computers within the bionic limb
decode those signals
to control powerful motors
on the bionic limb.
When the bionic limb moves,
the AMI muscles move back and forth,
sending signals through
the nerve to the brain,
enabling a person wearing the prosthesis
to experience natural sensations
of positions and movements
of the prosthesis.
Can these tissue-design principles
be used in an actual human being?
A few years ago, my good friend
Jim Ewing – of 34 years –
reached out to me for help.
Jim was in an a terrible
climbing accident.
He fell 50 feet in the Cayman Islands
when his rope failed to catch him
hitting the ground’s surface.
He suffered many, many injuries:
punctured lungs and many broken bones.
After his accident, he dreamed
of returning to his chosen sport
of mountain climbing,
but how might this be possible?
The answer was Team Cyborg,
a team of surgeons,
scientists and engineers
assembled at MIT to rebuild Jim
back to his former climbing prowess.
Team member Dr. Matthew Carty
amputated Jim’s badly damaged leg
at Brigham and Women’s Hospital in Boston,
using the AMI surgical procedure.
Tendon pulleys were created
and attached to Jim’s tibia bone
to reconnect the opposing muscles.
The AMI procedure
reestablished the neural link
between Jim’s ankle-foot
muscles and his brain.
When Jim moves his phantom limb,
the reconnected muscles
move in dynamic pairs,
causing signals of proprioception
to pass through nerves to the brain,
so Jim experiences normal sensations
with ankle-foot positions and movements,
even when blindfolded.
Here’s Jim at the MIT laboratory
after his surgeries.
We electrically linked Jim’s AMI muscles,
via the electrodes,
to a bionic limb,
and Jim quickly learned
how to move the bionic limb
in four distinct ankle-foot
movement directions.
We were excited by these results,
but then Jim stood up,
and what occurred was truly remarkable.
All the natural biomechanics
mediated by the central nervous system
emerged via the synthetic limb
as an involuntary, reflexive action.
All the intricacies of foot placement
during stair ascent –
(Applause)
emerged before our eyes.
Here’s Jim descending steps,
reaching with his bionic toe
to the next stair tread,
automatically exhibiting natural motions
without him even trying to move his limb.
Because Jim’s central nervous system
is receiving the proprioceptive signals,
it knows exactly how to control
the synthetic limb in a natural way.
Now, Jim moves and behaves
as if the synthetic limb is part of him.
For example, one day in the lab,
he accidentally stepped
on a roll of electrical tape.
Now, what do you do
when something’s stuck to your shoe?
You don’t reach down like this;
it’s way too awkward.
Instead, you shake it off,
and that’s exactly what Jim did
after being neurally connected to the limb
for just a few hours.
What was most interesting to me
is what Jim was telling us
he was experiencing.
He said, “The robot became part of me.”
Jim Ewing: The morning after the first
time I was attached to the robot,
my daughter came downstairs
and asked me how it felt to be a cyborg,
and my answer was
that I didn’t feel like a cyborg.
I felt like I had my leg,
and it wasn’t that I was
attached to the robot
so much as the robot was attached to me,
and the robot became part of me.
It became my leg pretty quickly.
Hugh Herr: Thank you.
(Applause)
By connecting Jim’s
nervous system bidirectionally
to his synthetic limb,
neurological embodiment was achieved.
I hypothesized that because Jim
can think and move his synthetic limb,
and because he can feel those movements
within his nervous system,
the prosthesis is no longer
a separate tool,
but an integral part of Jim,
an integral part of his body.
Because of this neurological embodiment,
Jim doesn’t feel like a cyborg.
He feels like he just has his leg back,
that he has his body back.
Now I’m often asked
when I’m going to be neurally linked
to my synthetic limbs bidirectionally,
when I’m going to become a cyborg.
The truth is, I’m hesitant
to become a cyborg.
Before my legs were amputated,
I was a terrible student.
I got D’s and often F’s in school.
Then, after my limbs were amputated,
I suddenly became an MIT professor.
(Laughter)
(Applause)
Now I’m worried that once I’m neurally
connected to my limbs once again,
my brain will remap
back to its not-so-bright self.
(Laughter)
But you know what, that’s OK,
because at MIT, I already have tenure.
(Laughter)
(Applause)
I believe the reach
of NeuroEmbodied Design
will extend far beyond limb replacement
and will carry humanity into realms
that fundamentally
redefine human potential.
In this 21st century,
designers will extend the nervous system
into powerfully strong exoskeletons
that humans can control
and feel with their minds.
Muscles within the body
can be reconfigured
for the control of powerful motors,
and to feel and sense
exoskeletal movements,
augmenting humans' strength,
jumping height and running speed.
In this 21st century, I believe humans
will become superheroes.
Humans may also extend their bodies
into non-anthropomorphic
structures, such as wings,
controlling and feeling each wing movement
within the nervous system.
Leonardo da Vinci said,
“When once you have tasted flight,
you will forever walk the earth
with your eyes turned skyward,
for there you have been
and there you will always long to return.”
During the twilight years of this century,
I believe humans will be unrecognizable
in morphology and dynamics
from what we are today.
Humanity will take flight and soar.
Jim Ewing fell to earth
and was badly broken,
but his eyes turned skyward,
where he always longed to return.
After his accident,
he not only dreamed to walk again,
but also to return to his chosen sport
of mountain climbing.
At MIT, Team Cyborg built Jim
a specialized limb for the vertical world,
a brain-controlled leg with full position
and movement sensations.
Using this technology,
Jim returned to the Cayman Islands,
the site of his accident,
rebuilt as a cyborg
to climb skyward once again.
(Crashing waves)
(Applause)
Thank you.
(Applause)
Ladies and gentlemen, Jim Ewing,
the first cyborg rock climber.
(Applause)