How Neuroscience Is Helping
Answer the Question ‘Who Am I?’
Simon
Worrall, National
Geographic AUGUST
26, 2015
Diseases of the mind like Alzheimer’s help us understand what it
means to exist or, conversely, feel as if we don’t
exist.
How do we know we exist? What is the self? These are some of the
questions science writer Anil Ananthaswamy asks in his
thought-provoking new book, The
Man Who Wasn’t There: Investigations Into the Strange New Science
of the Self.
The answers, he says, may lie in medical conditions like Cotard’s
syndrome, Alzheimer’s or body integrity identity disorder, which
causes some people to try and amputate their own limbs.
Speaking from Berkeley, California, he explains why Antarctic
explorer Ernest Shackleton fell victim to the
doppelgänger effect; how neuroscience is rewriting our ideas
about identity; and how a song by George Harrison of the Beatles
offers a critique of the Western view of the self.
You dedicate the book to “those of us who want to let go but
wonder, who is letting go and of what?” Explain that
statement.
We always hear within popular culture that we have to “let go,” as
a way of dealing with certain situations in our lives. And in some
sense you have to wonder about that statement because the person or
thing doing the letting go is also probably what has
to be let go.
In the book, I am trying to get behind the whole issue of what the
self is that has to do the letting go; and what aspects of the self
have to be let go of.
You start your book
with Alzheimer’s.Tell us about the
origin of the condition and what it tells us about “the
autobiographical self.”
Alzheimer’s is a very severe condition, especially during the mid-
to late stages, which starts robbing people of their ability to
remember anything that’s happening to them. They also start
forgetting the people they are close to.
When you look at it from the perspective of the self, what
Alzheimer’s is doing is eroding your narrative or autobiographical
self. This is the story we tell others about who we are, and the
story we tell ourselves. It’s not necessarily something we’re
consciously thinking. It is a narrative built upon episodes that
have happened in our lives.
What Alzheimer’s does is make it well nigh impossible to have new
memories, so your narrative stops forming. As Alzheimer’s
progresses it then starts eating into existing memories and eroding
your earlier narrative self.
Several of your case studies are of extreme conditions shared by a
small minority of people,
like Cotard’s
syndrome. Why
should the rest of us care?
They are extreme conditions, especially Cotard’s because there are
only a few hundred cases recorded in medical literature. But it’s
when things go awry that we get a peek into how certain processes
in the brain work. If everything is going OK, we don’t get a handle
on what is happening.
For instance, the feeling of existence that we all have. We never
question why we feel that we exist. It seems such an obvious thing
to say, "I exist." Of course I do! But then you have a condition
like Cotard’s, where a person is claiming, "I don’t
exist."
That instantly raises the question of what it means to say "I don’t
exist." What are the processes in the brain that have gone wrong,
which are making the person have such a strong conviction about not
existing? Conversely, it tells us what it might mean to say, "I
exist."
How are advances in neuroscience changing
our understanding of the self?
They’re giving us a peek into the various processes that are going
on in the brain and the body, and I want to keep emphasizing that
it’s the brain and body together. It’s giving us a sense
that the self is not some monolithic thing sitting in the brain or
outside the brain. It’s actually a whole set of neuro-processes,
which need to work in concert for us to have a sense that we have a
being, that we are an entity to whom things are happening and have
a perspective on the world.
We look out on the world from behind our eyes, and we have a sense
that everything we perceive is somehow private to us. So it’s
shedding light on all these various aspects of the self.
The chapter “The Man Who Didn’t Want His Leg” sounds like a Monty
Python sketch. But there really are people who want to amputate
their own limbs, aren’t there? Tell us
about apotemnophilia.
Apotemnophilia was the name given to the condition when it was
first written about in modern medical literature. Now it’s
called body integrity identity disorder,
or xenomelia,
which means foreign limb. The fact that neuroscientists are still
struggling to name it is an indication that they are still trying
to understand what’s happening here.
One of the best ways to get a handle on what might be happening is
to think of the condition most people will be familiar with, which
is phantom limb. Phantom limb is a situation where, when people
have had an amputation, they continue to feel the presence of their
limb. This raises the question as to what it is that you are
perceiving. Why do you continue to feel a limb that is not
there?
One answer is that the brain creates “maps” of the body and what we
perceive are these maps. In the case of phantom limbs, the map
should have reorganized to reflect the current physical condition
of the body. But it hasn’t and you continue to feel the old
map.
Now, imagine the inverse condition, where your body is functioning
well but the way the brain has mapped some body part is not OK.
That is body integrity identity disorder, where people feel a lack
of ownership of some part of their body. The suffering can get so
extreme that people will try and amputate a limb and in order to
feel more “complete.”
You say we do not just receive sensations from the outside world
but from inside the body. Explain that paradox.
The brain is basically an organ that monitors sensations that the
body is getting from the outside through our ears, eyes, nose, and
skin etc. But it also has to keep track of what’s
happening within the body. In fact, in some sense,
its primary purpose is to keep the body in a favorable
physiological state for survival. The way it does this is by having
a lot of information coming into the brain from within the body,
things like, how does the brain know what the blood pressure is or
the temperature of the viscera?
Receptors in our joints and tendons also tell the brain about the
three-dimensional location of the various body parts in relation to
one another, which helps the brain construct a sense of the bodily
self. If you close your eyes and don’t look at your body, you
still have a sense of how your body is positioned in
three-dimensional space. That is because of the information coming
from within your body. The brain needs all of that to make sense of
what the body is doing in its environment.
You say that self-awareness gave humans an evolutionary advantage.
How?
When we developed memory and an awareness of ourselves as entities
spanning time, it would have made it easier to plan—knowing how
things would unfold in the future, or how things had happened in
the past. All of these would have been survival
advantages.
The doppelgänger effect
was experienced by, among others, the Antarctic
explorer Ernest
Shackleton. What was going
on?
It was at the very end of Shackleton’s expedition. A large number
of team members had already become stranded in the Antarctic ice,
so Shackleton and three other team members tried to get help. They
were extremely exhausted, and all the team members reported sensing
the presence of another person alongside them. It is a condition
that a lot of mountaineers talk about. It seems to be caused by
some malfunctioning of the brain’s processes under extreme
exhaustion and oxygen deprivation.
One of my favorite George Harrison songs
is I Me Mine.
What’s the message of the song in relation to the
self?
I Me Mine can
be thought of as the different layers of the self. The “I” is the
part that is at the core of being a self: the thing that is the
subject of experiences and to which things are happening. Me and
mine are extensions of that. You look at your body and say all of
this is “me.” There are also aspects to the self that you
appropriate, like your house or family or friends and those become
“mine.” So the song is basically telling you about the progression
of the way the self feels within us, and is probably constructed
within us.
Epilepsy can trigger ecstatic experiences, akin to those of mystics
and visionaries. Tell us
about Aldous Huxley’s experiments.
There is a tradition within literature of ecstatic seizure caused
by epilepsy, particularly in the work of Fyodor
Dostoyevsky, who was an epileptic himself.
Huxley’s Doors of
Perception is about his experiences with
mescaline, which he took under the supervision of his
psychiatrist, Humphrey
Osman.
He basically had what would today be called a psychedelic
experience. The word "psychedelic" didn’t exist to describe what
was happening, but he had an experience in which things that would
otherwise have seemed ordinary, like a flower vase, became imbued
with a sense of vividness and vitality. One very striking thing he
describes is how his sense of time slowed down. In fact, he
completely lost his sense of time.
You end your journey in search of the self
in Varanasi,
in your native India, with the question, “ Who am I?” Did you find
the answer? And what keys may Buddhism hold for
us?
After working on this book I came away with the sense that the
debate over whether there is a self or whether there is no self is
still ongoing but at a very subtle level. I think philosophers and
neuroscientists agree that a lot of things we think make up the
self are just neuro-processes in the brain, creating an impression
of a seemingly solid entity. But actually these things can be
disrupted, like your narrative self or even your sense of what your
body is. The question of whether there is something at the very
base of it all is an open question that neither philosophy nor
neuroscience has answered.
The trip to Varanasi didn’t help answer these questions. It was
more a way to write about a place where someone tried to answer
these questions a long, long time ago and that was
Buddha.
Cartesian
dualism separated the mind and body, giving
the mind a place apart from the body and placing it on a pedestal.
Neuroscientists have walked away from that because it’s clear that
the mind is not some separate entity that exists independent of the
body. Body, brain, and mind are all interlinked. The
basic
Buddhist idea is that our attachment to the self, to the things we
think we are, and our unwillingness to let go, is the cause of
suffering, because these are all constructed entities. An
illusion.