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It is the most fundamental experience of all defining our waking moments and giving rise to all that we think and feel
Without consciousness
we have no way of proving we or anything else exists and
Yet what it is and why we have it remain a mystery that some of the greatest minds have been unable to solve
The only way I know I exist is because I'm conscious I wake up in the dark of a hotel room I'm
Discombobulated because I'm jet-lagged. I've no idea where I am Who I am and what country I am yet
I know I exist because I see something
Rapid advances in our understanding of how the brain works might one day allow us to pinpoint the parts of the brain that generate consciousness
But will something as objective as science be able to explain what it feels like to be us
Consciousness - nature is private. It's subjective
I know about my consciousness from the first-person point of view other people don't know about my consciousness very indirectly
Philosophers have been trying to answer some of these questions for millennia in the past couple of centuries scientists have joined them
Debate can be fierce
In fact some scholars reckon, the puzzle of consciousness is something that human mind is incapable of solving. I think that's
Not just wrong. I think it's it's
Culpably wrong it isn't impossible at all. It's just that we have to buckle down and do it
One thing that both disciplines can agree on is that consciousness arises in the brain
Made up of roughly 85 billion neurons and other supporting cells about which we know little the brain consumes almost 20 percent of our energy
Despite comprising just 2% of our mass
Every so often I get kind of interested in astronomy and cosmology because you look out there and you think oh gosh
This is amazing. You know, it's almost limitless
but then I turn around and kind of
Introspective and think about the brain and it's kind of like a universe within
We're a long ways of understanding how it works. But if we can get down to figuring out how a neuron works
By God, then we could deal with it two neurons and then four neurons and four million neurons and then a hundred million
Helped by developments in imaging partly pioneered by dr
Reichal and his team scientists can study in some detail the two enormous folded sheets of out of rain called the cerebral cortex
This plays a crucial role in higher brain functions like memory perception thought and language
and I have two of them in my left hand height and
And it's part of this sheet that gives eyes to consciousness this sheet
Also give rise to intelligence and reasoning and all the other things that we hold dear
But the what the human brain in the human mind Christophe Kok wants to come up with a satisfactory
scientific theory of consciousness before he dies
Science wants to explain everything if if science fails to explain the central fact of my existence. I
Would say then it's a it's it's a failure
In order to gain a better understanding of how parts of the brain work scientists often. Look at bits of it that are broken
It's a little part of the brain called the cerebellum, which is at the back of my brain
If I lose it
I will be unable to let's say to dance or beer or climb and her difficulty moving my speech becomes slurred but
My consciousness will not be impaired
On the flip side. It seems that some parts of the brain may be essential for consciousness
Identifying these so called neural correlates of consciousness would help pin down what is happening?
What might the NCC the neural correlates of consciousness be like
Assuming that it is that it's an emergent and neuro scientific and let me say straight away that we don't know was his life
Before his death in 2004 Francis Crick the co-discoverer of the structure of DNA
Worked with dr. Cock on something. They termed the binding problem
Put simply the binding problem asks how the brain integrates different bits of information it gets both sensory and internal
into our conscious experience
in real life the brain is terribly good and puts everything together the movement the shape and
and the color
The usual way of saying the binding problem is if you have a red square and a green triangle
How is it that you don't have see it as that get the colors mixed up with the shapes. That's basically the problem
Because our experience of consciousness is derived from the data we get from lots of different systems the visual and motor being just two
The two men looked at a part of the brain that is connected to all these regions
They were especially interested in the claustrum a thin sheet of nerve cells that sits at the bottom of the cerebral cortex
in each hemisphere of the brain
Because testing the claustrum in a live human brain is invasive and risky. No formal experiments have been done
But one happened accidentally last year when a neurologist trying to understand the source of his patient's epilepsy implanted electrodes near her claustro
When he switched the current on she lost consciousness as soon as he switched it off. She regained it
No one knows why we have consciousness
It's one of the big mysteries
Why did evolution bother putting consciousness in how did evolution put consciousness in?
Why couldn't we have done everything that we do with a set of objective mechanisms and no first-person subjective experience of the world
It's one of the biggest questions and philosophy in science just as the processes of consciousness remain a mystery
So does its purpose is it a high-level summary?
the brain generates to help us plan for what comes next a
Clever way of designing our brains to make us more adept at being social neither both
One evolutionary explanation for why we have consciousness suggested an animal capable of modeling the behavior of another can anticipate it to its advantage
The surprising thing is that so few animals actually have this ability
Humans have it
so I have a very good idea of what you're going to do and when you're going to do it and why you're going to
do it and
Children starting it maybe around three years old get that Janet Metcalf
the theory of mind a theory of mind is actually misnomer the way we tested is whether a person
or an animal
Can give evidence that they can get into the other person's shoes or the other person's mind and see the world from that
person's perspective
now the
the test of it is often not just can you see from the viewpoint of the other person but could you see that someone has
a different viewpoint from your own
the theory of mind might provide one way of working out if animals other than humans are conscious the
Only species that we're absolutely sure has theory of mind is human
and
maybe
humans older than
roughly three years old
It's very controversial whether any other animals have it. They're arguing about whether chimps have theory of mind or not
Before we can have a theory of mind
We must recognize ourselves for decades scientists have used something called the Rouge test to see whether animals do just that
Human babies do from about eighteen months old
Chimpanzees presented with mirrors soon use them to groom themselves much as we do
Elephants dolphins and Magpies also can respond to mirrors in ways that suggest self recognition
The problem with the roush test that the animal researchers
Always raise is that maybe there? It's just body knowledge
That it's not mind knowledge
so it was interpreted as the animal knowing that they have a mind and
Theory of mind as we normally think that is related to another person not to the self
But presumably you have to know that you have a mind before you project that same capability onto someone else
Identifying the neural correlates of self recognition in animals would be a hard task
But if we were able to do it comparative studies would be possible
That would be hugely valuable
Science is edging closer to understanding what parts of the brain might be involved in generating conscious experience
By some estimates we may not be far away from an empirically sound theory of consciousness and how it evolved
But could a physical theory ever satisfactorily address what it is that people are feeling when they are conscious
David Chalmers calls consciousness the hard problem a deft description for something that is hard to explain and hard to solve
The methods of science right now are great for explaining objective processes and objective functions
So when it comes even to explaining things like the behavior of an organism
You can tell some story about a bit of the brain a neural process or a computer leg process in the brain
That makes us behave a certain way, but the problem of consciousness what we call the hard problem of consciousness, which is explaining
How you get subjective experience from the brain is not that kind of question
It's not a question about how we behave it's a question about
You know what? It's like about how it feels from the inside and looks like you can explain all those
Objective mechanisms and objective processes and you still won't have answered the hard problem which is why is it that all that functioning is?
accompanied by consciousness
The hard problem divides philosophers and scientists alike
some philosophers argue that consciousness can be explained far more simply a
lot of puzzles Bell mysteries
We're going to understand it from the bottom up and from the top down. I
Have no doubt about that
Daniel Dennett argues that consciousness is nothing more than a cognitive illusion that science will into course explain
Our brains have been designed by evolution and then redesigned by cultural evolution
to give us a
user-friendly
System of things in the world that we deal with so
the
user-friendly world that we live in the manifest image is a sort of
friendly user illusion in the same way that the
Desktop of your laptop is a user illusion it simplifies and it distorts in
Helpful ways for most purposes if you really want to know what's going on
You have to go backstage and the same thing is true about the bay
Until recently we didn't have very good tools for doing it the brain was just
off limits as off-limits as
distant galaxies
we're now developing the tools for non-invasively studying the brain and we're now developing the
Computational ideas
and models so that we can understand how a brain can non miraculously deal with information and
refine it and
uncover the
semantics of the world or outside and inside
So we're now we now have the toolkit and it's taken this long to develop it now. We just have to use the tools
Perhaps but for the time being the puzzle of consciousness continues to pose more questions than it does answers
Yet another philosopher Pythagoras of Abdera proclaimed that man is the measure of all things
Until the problem of consciousness is solved though. That might better be phrased the measure of all things but himself