Free will and neuroscience | Krystèle Appourchaux | TEDxMaussanelesAlpilles

What is our free will? The neurosciences do not grant us one; but is there still hope?

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So, the title of my presentation is:
"Free will and neuroscience".

I will start, as would
a good philosopher,

by defining the terms,

as if I were going to write an essay,
but that won't be the case, don't worry.

Free will is the capacity
to choose freely,

the capacity we have
to determine our own will.

It is a notion first introduced
by Saint Augustine of Hippo

in the 4th century A.D.

Originally, it was meant
to justify the existence of evil,

in that, for Saint Augustine,

it was not possible that God desired evil,

though evil exists, it's a fact.

So, it's man that is responsible for evil,

and so, man must be free
in his actions and choices.

Today, the advancements of neuroscience -

so, neuroscience is all those sciences

that study the brain, the nervous system,

bringing together anatomy, physiology,

as well as psychology,
informatics and mathematics.

So, all these different disciplines
came together in the sixties and seventies

and pooled their data and methodologies

in order to study the brain.

What we find is that
neuroscience tell us today

that we don't have a free will.

I'd like, in the next few minutes,
to examine with you

whether the data are, in fact, alarming,

and whether it's not the case

that we actually don't have
any capacity to choose freely,

or if there's still a little hope for us,

and we do, perhaps, have this capacity,

and, if so, to what extent.

You could object:

"OK, but it's nothing new,

science has been telling us
ever since the 18th century

that cause-and-effect
is a universal law,

and when I know what happened
at any given moment,

I can predict what will happen tomorrow,

or I can infer what happened in the past."

This was indeed the idea Laplace had
at the beginning of the 19th century,

who formulated this idea,

by saying for that a supreme intelligence,
an omniscient intelligence,

that at any given moment
knew every force driving nature

and the respective positions
of everything that composed it,

with, furthermore,
a sufficiently vast intelligence

to analyse all this data,

embracing in the same formula

the movements of the largest
bodies of the universe

and those of the lightest atom,

nothing would be uncertain to it,

and the future, and likewise the past,
would be visible to its eyes.

So, this is the idea that was
fundamental to classical physics,

which is still used today,

since scientists try to ascertain
regularities, "the laws of nature".

Well, man is part of nature.

So, do we equally obey
nature's regularities, it's "laws",

or do we reside outside this universe?

If we adopt a materialistic point of view,
which, today, is the most common one,

man is part of nature,

and it should be possible to explain
his behaviour, his choices, his actions,

in a deterministic way.

But neuroscience yields further data
to be added to this fundamental position,

since the experiments
of Benjamin Libet in the eighties -

if I can bring it up ... there we are -

the experiments of
Benjamin Libet in the eighties,

showed that an electric potential
is produced in our brain,

a few hundred milliseconds

before we are conscient
of our decision to act.

So, how did he show that?

He asked some participants

whose heads were wired up
for an electroencephalogram,

with an electromyogram recording
muscular activity in their hands -

already we're made to feel
really free, don't you think -

he asked them to look at this dial

and to just let come a spontaneous desire
to raise their index finger.

Simply that.

And, to him, this was ...

the ultimate representation
of our free will.

Well, that's debatable.

But, anyway, while the subject
stared at the dial

and let the desire to flex
their index finger just come to them

without determining beforehand
the moment they would to do it,

but, nonetheless, letting known

where the luminous dot on the dial was
when they made the decision -

all quite complicated -

he asked them to indicate
the moment they made their decision,

while all the while
their cerebral activity was recorded.

They showed, Benjamin Libet and his team,

that an electric potential
is produced in their brain

500 milliseconds before the action,

and 300 milliseconds before the subject's
conscient decision to raise the finger.

This tends to indicate

that our brain, in some way,
initiates, triggers the action,

even before we are conscient
of wanting to raise our finger.

This, therefore, in effect,
puts into question

the tenet of free will,

according to which, we are the ultimate
source of our acts, of our choices.

There's no ultimate source,
since everything is predetermined

by cerebral, unconscious events

that are completely
outside our conscious mind.

Perhaps I can go on to the next slide.

Yes.

Or this one, in fact.

This just shows the timescale of events.

So there, you see the electric
potential in the brain,

so, inconscient,

there, the conscious decision,

and here the motor action.

So, this is the order
in which events take place.

I've tried, in my book,

"Un nouveau libre arbitre"
["A new free will"],

to include this data,

to take it into account,

and to consider whether these experiments
could, nonetheless, leave room

for a certain capacity of free will.

The redefinition I propose
revolves around two points.

Firstly, let's say,

it has been proved that certain
unconscious processes

can still be the subject
of the conscious mind.

I'll start again:

famous psychological experiments showed

that when we make a choice, a decision,

most of the time,

we are not conscious of the causes
determining our choice.

For example, a Swedish team
demonstrated that

when we ask a participant shown two faces
to choose the one they prefer,

and we magically show them
the picture they didn't choose,

but we ask them: "Why did you
choose this picture?" -

it's totally mean -

effectively, the person will rationalize
that choice that they didn't make.

They will say, "That person
had a nicer smile" etc, etc.

Furthermore, this protocol has been
reproduced in the form of an interview

where the participant is induced
to maintain their attention

on the cognitive processes
that brought them to a particular choice.

In other words, when we ask them
why they chose a particular face,

most often, the most probable reasons
are automatically arrived at.

They don't take the time

to go back to the moment
they chose the image

and what precisely, conclusively,
led to their choice,

what they saw and felt,

what they felt emotionally
in relation to the face, for example.

This interview technique allows us

to look at the results of the Swedish
team in an opposite way.

When the participants
are approached in this way,

they detect the manipulation
in 80% of cases,

while before, they were
manipulated without realizing it

and they rationalized a choice
they didn't make in 80% of cases.

So, what this says is that extending
our own consciousness is possible.

Inconscient processes
can become conscient

by redirecting our attention.

And this is one part of the definition
I want to put to you today:

that free will is not the capacity

to be the ultimate source of our acts.

There are, of course, lots of things
that determine us,

but we can, to a certain extent,
develop this capacity,

so it's a learning process,

not something we can presume
to have by nature,

rather a training
of our attentional skills.

And the other part of my redefinition -

if I can go on to the next slide -

There are also neuroscience experiments
concerning the Stroop effect.

The Stroop effect,
very well known in psychology,

is the effect that we have,

whereby if I ask you
the colour of this word,

it's easier and quicker for you to answer

than if I ask you the colour
of the word down here -

even more so if you are English speakers,

since the words are in English -

simply because at the top,

the colour of the ink
matches that given by the word,

while at the bottom,

the colour of the ink does not
match that given by the word

This effect is highly automatic,

something we cannot control.

But a researcher at
McGill University in Montreal,

called Amir Raz,

showed that this effect
could actually be deautomatized.

So a very automatic effect like this one

can be deautomatized
by hypnotic suggestion

to interpret this chain of letters
as a meaningless chain.

Therefore, if we hypnotize
one of the participants of the study,

telling them that this chain
of words means nothing,

the automatic effect will be
deautomatized and reduced.

This means that even some unconscious,
highly automated processes

can be modified.

And so some of the behaviours
we exhibit every day

that are highly automatic

are sometimes very useful,

like when driving, it's better
not to continually ask ourselves questions

about what we need to do
with the pedals, the gearbox, etc.,

at some point, it becomes
very automatic and so much better,

while other behaviours
we'd sometimes like to abandon,

like, for example,
smoking 30 cigarettes a day,

or stuffing down a box of cookies we fancy

because we haven't the self-control -

these types of compulsions.

It shows, in fact, that these behaviours
that have become automatized with time

can be deautomatized

to let us find again
some sort of flexibility

and to expand the inventory
of available actions.

So there.

So, to sum up,

there's the idea that neuroscience
put to us to start out with

that our free will could be compromised

since, effectively, there are
inconscient precursors to our actions

that we don't necessarily
have control over,

and it would seem we are dictated to
by these unconscious precursors.

But then neuroscience itself
shows us round this:

attention is an essential ability we have

that modulates what will or will not
enter our consciousness.

And so, I just wanted to show you
that free will still exists,

but that it might be a bit more
difficult to access it,

that it necessitates the long-term
training of our attentional skills.

And I thank you for your attention.

(Applause)