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WHY AM I aware of anything at all? Wouldn’t life be a lot simpler without
consciousness? Certainly science would be. But, unfortunately or not, this
‘experience of being’ will not go away. Now, after several decades of trying
to ignore it, science is once again tackling the elusive and difficult problem
of consciousness. Researchers in the neurosciences may yet produce experimental
results that shed light on that long-standing philosophical conundrum, the
nature of ‘self’.

One physiological study, by Benjamin Libet at the University of California
at San Francisco, has already produced interesting results. His work suggests
that it takes time for the brain to produce consciousness – about half a
second, in fact. He reached this conclusion by studying patients who had
electrodes inserted into the cortex of their brains. By stimulating the
electrodes, he could give these people the sensation that their arm had
been touched, but only if the electrical stimulation lasted for at least
half a second. This finding seems to suggest that it takes half a second
of brain activity to produce awareness. We are left with the odd conclusion
that we are experiencing everything half a second after it happens. When
someone taps me on the shoulder, I react first and become aware of if only
later. It is an illusion that I turned round because I felt the heat. Conscious
awareness is more like an afterthought.

This process might serve to restrict vast amounts of unnecessary information
from entering consciousness. But what is this ‘consciousness’ which information
‘enters’? Surely it is not a thing or a place. But there must be some difference
between whatever is ‘in consciousness’ and the vast mass of processes constantly
going on in the brain that are obviously ‘unconscious’. So what is this
difference? These questions reveal the depth of our ignorance and confusion
over consciousness.

Part of the problem is its reflexive nature. Conscious- ness cannot
be studied in the same way as the things I am conscious of. If I turn my
attention to it, it ceases to be consciousness and becomes just another
thought or experience.

Another problem is its ever-changing quality. What it means to be conscious
is essentially what it is like being me, here and now. And yet as soon as
I think that, here and now are already gone: I, and the world around me,
have changed. That is why William James, one of the 19th-century pioneers
of psychology, used the phrase ‘the stream of consciousness’. It is a stream
that is flowing; it feels unbroken but never repeats itself exactly. Science
searches for patterns and regularity, so it is hard to know where to start
with something whose very nature lies in change.

The best starting place with such problems is always to re-examine the
question. Asking ‘What is consciousness?’ is, according to many people,
a meaningless question, for con-sciousness is not a ‘thing’ at all.

A more tractable question is, ‘Why do we have consciousness?’ It might
be possible to imagine animals (or even machines) that could carry out all
the actions I carry out and yet be blissfully unaware of anything at all.
Those in pain, or who enjoy the occasional oblivion of alcohol, might even
think this would be preferable. So why did consciousness evolve? Evolution
must have had some reason for making us conscious – mustn’t it?

John Crook, an ethologist at the University of Bristol, has argued that
human consciousness is distinctive because we are conscious of being conscious;
we have a sense of having personal power over our actions and we have self-identity.
These together with language, arose, he argues, because our ancestors began
using tools. Only an animal that needs to know who owns and uses which tools
needs such a strong sense of personal identity.

By contrast the psychologist and writer, Nicholas Humphrey, argues that
we evolved self-awareness for social reasons: to hold together a cooperative
society, early humans needed to understand their fellows – to become, in
Humphrey’s words, Homo psychologicus. The best way to do that, Humphrey
argues, was to use a ‘privileged picture’ of themselves as a model for what
it is like to be another person. So, according to Humphrey, we learnt to
look into our own mental processes so as to be able to predict (and hence
control?) the desires or actions of others.

This connection between consciousness and representing the self is made
even more explicit by Richard Dawkins, a zoologist at the University of
Oxford. He says: ‘Perhaps consciousness arises when the brain’s simulation
of the world becomes so complete that it has to include a model of itself.’
And yet there is something wrong here. The brain is not really modelling
itself. It is not an image of neurons and glial cells that is central to
my self-consciousness. Surely people who have never learnt about the structure
and function of the brain are just as conscious as neurosurgeons.

Was Homer unaware of himself?

According to all these theories, self-awareness would have appeared
very early in the evolution of humans. By contrast, an American psychologist,
Julian Jaynes, proposed the controversial thesis that consciousness appeared
only in historical times. The early Greeks and the Hebrews of the early
Old Testament period did not, according to Jaynes, experience themselves
as thinking beings. Instead of attributing their verbal images to internal
processes they attributed them to the voices of the Gods. He cites the Iliad,
written about 3000 years ago, as having no references to mental concepts
such as mind, thoughts, feelings, or even self. People were not to be blamed
or held responsible for their actions: they were only instruments of external
forces.

This interesting idea puts our views of ourselves in a new light. If
the Gods were only a theory invented to account for behaviour, perhaps our
present-day concept of self is just another such theory invented to explain
ourselves to ourselves. It may be a better theory than the Gods but is it
really accurate? Isn’t it just another useful illusion?

The problem with all these theories is that none of them directly addresses
the question of consciousness itself. Why couldn’t a system evolve with
a good concept of self, attributing behaviour to internal processes – even
with psychological skills modelling other people’s (non- conscious) behaviour
– without actually feeling like anything? These theories may show how self-identity
or the ability to predict behaviour arose, but they say nothing directly
about awareness. I can still imagine an animal or machine that does all
these things and is completely unaware.

Perhaps, you might say, it is not just passive awareness that distinguishes
us from unconscious automata, but the fact that we can consciously control
what we do. Recent research, however, reveals that this too may be (partly
or wholly) another illusion.

Michael Gazzanioa, a neuroscientist at Cornell University in New York
State, has studied ‘split brain’ patients – the left and right sides of
their brains have been surgically separated (often as a treatment for severe
epilepsy). In most people, the ability to use language is by and large localised
in the left brain; but one of his patients had some verbal ability in both
halves, although only the left could produce speech. When a written command,
such as ‘laugh’, was presented only to the part of the visual field linked
to the right brain, he laughed. When asked ‘Why did you laugh?’ he answered,
using the left side of the brain, but simply fabricated a reason: ‘Oh, you
guys are really something!’ The left hemisphere had apparently observed
the laughter and tried to account for it somehow. This may be no quirk of
split brains. Most of our reasons for action may be totally unavailable
to conscious introspection. Our verbal selves may make up plausible reasons
for the actions they observe their body making.

Research on split brains has revealed much more about the nature of
consciousness. In some cases, each half brain displays separate desires,
intentions and even hopes for the future – and a sense of self. It is easy
to think that splitting the brain has split an originally single consciousness,
but Gazzanioa believes that the surgery only reveals a general principle:
that human minds are multiple entities consisting of many subsystems. It
is only the ability to put things into words that creates ‘a personal sense
of conscious reality out of the multiple systems present’, he believes.

So is the idea of a single conscious ‘will’ totally false? Here again
some recent research provides a clue. Libet turned his attention from conscious
sensation to voluntary action and devised an ingenious experiment based
on earlier work. Using electrodes fixed to the scalp, other researchers
had found that just before someone does something voluntarily the electrical
potential of the scalp shifts to the negative, a phenomenon called the readiness
potential.

Electrodes pick up readiness potential a second or more before any apparently
voluntary movement begins. We might assume, then, that the conscious decision
to act must come before the readiness potential, if a conscious decision
to act is what starts the train of events. Libet set out to test this. He
asked subjects to flex their wrist or fingers at any time they felt the
‘urge’ or desire to do so. To measure the timing of that urge or desire,
he asked them also to watch a revolving spot and to report its clock position
at the time they felt the urge to move.

Consciousness is an afterthought

His findings were consistent and surprising. The readiness potential
came first and the desire to move about 400 milliseconds (nearly half a
second) later. The implication seems to be that even in apparently spontaneous
voluntary acts, an unconscious brain event happens well before any conscious
desire or decision to act. Again, the consciousness seems to be an afterthought.

Libet went on to show that subjects could ‘veto’ the action within a
period of between 100 and 200 milliseconds before the action would have
started. This, he argues, still leaves some potential role for the ‘will’.
Other scientists have argued, however, for more extreme interpretations
of his data. The experiments could mean that we do not directly experience
an intention to act at all. Rather, we might infer an urge or desire to
act after the process has already begun unconsciously. Because this urge
precedes the action, we can keep up the illusion that it causes the action
– but it is only an illusion. According to this view, consciousness has
no active role at all.

This dispute reflects the long philosophical argument over whether mental
events, anything from the desire for ice cream to the sensation of pain,
can cause physiological events in the brain. Libet maintains they can. He
thinks there is still room for the ‘will’, which can intervene to stop physiological
processes when required. Others prefer to use his findings as evidence that
they cannot. The important question for us is whether science is on the
verge of turning a difficult philosophical problem into an empirical one.

Many researchers have argued that consciousness can be modelled by computing
systems, and many debates focus on whether consciousness is then associated
with the highest level of such a system. Such discussions may help to explain
aspects of the working brain. But no such theory can explain why the contents
of one part (whichever part it may be) should have the quality of feeling
like something while the rest do not.

The American philosopher Thomas Nagel made this crucial point about
consciousness in his now famous paper entitled ‘What is it like to be a
bat?’, published in his collection of essays Mortal Questions. His point
was that when we say something is conscious, we essentially mean that there
is something it is like to be that thing. Now if humans are complex information-processing
systems, why should there be ‘something it is like to be’ some levels of
that system but not others? Whichever part of the system you choose, the
essential mystery remains untouched.

A radical solution is to sweep this question away and say that all mental
models are conscious. Mental models are the internal representations of
the world which computers, as well as animals and humans, use to control
their behaviour. You could not get around without a good model of your own
body and the world around it. I am suggesting that it is not like anything
to be the skin, blood or bones of a bat, but it is like something to be
the bat’s model of a bat. This is equivalent to saying that there cannot
be such things as not-conscious mental models.

The major objection to this theory is that it does not seem to us as
though all the many models our brain constructs are conscious. But the answer
all hinges upon who that ‘us’ is. What am ‘I’ who is to be conscious of
all that activity? We can suggest an answer. ‘I’ am only one of the models
in the system, a model of ‘self in the world’ built largely by language.
‘I’ am a self-image, a body image, a construct of a human being. This makes
it perfectly obvious why all the rest of the system appears to be unconscious.
It is unconscious to ‘me’ but not to itself.

Before we start thinking of human systems as peopled by infinite conscious
models, we should reflect what it would be like to be most of those models.
I think the answer is not much. For example, the models in the lower levels
of perceptual processing entail no concept of self, action or an external
world. Their consciousness would be correspondingly limited. Only the complex
model of ‘self in the world’ sustains full reflexive awareness – consciousness
of being conscious. It is this which seems to be ‘me’.

Most of us have only one of these (unless you include any ‘dream selves’).
Presumably people with so-called multiple personalities have several models
of self, each conscious in its own way and competing for dominance. This
situation is abnormal, but now we can see it as only an extreme form of
the normal case. Every human brain constructs multiple conscious models,
but there is only one ‘me’, my model of self.

This makes sense, too, of the phenomenon of selective attention. When
‘I’ turn my attention to something, that thing seems to come into my awareness.
From a computational point of view, we might say that the system has incorporated
the model of that thing into the model of self. So ‘I’ become aware of it,
and it of ‘me’.

In this view, there need be no top and bottom, no one consciousness
controlling the rest. Consciousness is not something that controls. It is
not a thing, a place, a substance or a part of the system. Indeed, it has
no function. It is only what it is like being a mental model.

This approach transforms the whole evolutionary question. There is no
definite point at which consciousness arises, nor any purpose for it at
all. Any organism that constructs representations (as even the most primitive
will do) will have correspondingly primitive consciousness. Those that model
a self will also be conscious of self. As evolution progresses, the quality
of consciousness depends on the kinds of models constructed. So perhaps
Jaynes had a point. Once the voices of the Gods were replaced by a concept
of an active self, self-consciousness took another step forward.

And what will our next step be? On this view, the mystics’ search for
higher consciousness or the Buddhists’ training for ‘enlightment’ may be
no idle fancy but steps into new mental models.

Mind and meditation

At the heart of Buddhist training lie the skills of meditation and mindfulness.
Pursued far enough, these are supposed to transform consciousness and free
the trainee from suffering. Does it help us to understand this transformation
to ask how the models of reality are changed?

Most of us, claimed the Buddha, are constantly distracted by sights,
sounds and ideas. We live in a whirl of confusion and fantasy: more in the
past or future than in the present moment. Struggling to find happiness,
we cling desperately to our concept of self and the things we think will
make that self happy. But this, paradoxically, is precisely what leads to
suffering.

By contrast, mindfulness means living in the present moment, every moment,
constantly alert. In meditation, this skill is practised in quiet sitting.
Any thoughts that arise are let go again. They may come again and again,
but there is no clinging, no leap into the building of fantasies. They just
come and go until eventually the mind is still.

These contrasting ways of being can be understood in terms of the mental
models that are constructed. In the normal way, attention shifts from one
thing to another. Surprising events grab the attention: other chains of
thought wait to be finished as soon as there is a gap. So there is never
any peace. This is efficient in using all available processing capacity,
but what does it feel like to be the models in such a system? I suppose
it feels like most of us do feel – pretty confusing. The only thing that
gives it any stability is the constant presence of a stable self model.
No wonder we cling to it.

On the other hand, being mindful means not following every association;
not stacking up ideas to be completed; not rehearsing, planning or even
selecting. The models become ever simpler and all processing capacity is
not immediately used up.

More and more can be linked into one model because there is less and
less being modelled. And what would it be like to be the models in such
a system? Obviously very different. Is this why everything seems brighter
and more ‘real’ during meditation? Why the quietest sound is clearly heard
and the beating of one’s heart is constantly present? If so, testable predictions
might follow. Long-term practitioners might show greater awareness of normally
inaccessible low-level modelling, for example.

In the end, it is not even necessary for the model of self to be constructed
at all. Imagine what it would be like to be a system that processes incoming
information but builds no further constructions upon it, not even any self
to observe. With no modelled distinction between self and other, I imagine
the world would all seem one. (This condition might make survival problematic,
however.)

People who have this training and experience find it very hard to describe
what happens, which is no wonder when ‘they’ (their model of self) have
been dissolved. It may, in fact, be impossible to describe using the assumptions
of our usual language. But perhaps a new possibility now arises: that science
might at least develop the concepts and language needed to understand mystical
experiences in terms of information processing.

Buddhism teaches the doctrine of ‘no-self’. There is no thing that is
conscious but just consciousness itself. Cognitive psychology reveals that
the self is a mental model; if consciousness is just what it is like being
a mental model, there is no self being conscious of anything, but just a
series of changing models.

So can I now answer my question: ‘Why am I aware of anything?’ The answer
seems to be that because I am only a mental model, it could not be otherwise.

Dr Susan Blackmore is a researcher in the Brain and Perception Laboratory
at the University of Bristol.