The Illusion of Now

everything you’re experiencing

right here right now took place half a

second ago

what’s more you couldn’t be anywhere

other than

right here right now

and to expand on that idea and to

justify if you like

i’m now going to explore with you three

different ideas

okay the first of those ideas is that

our experiences of the world

are our best interpretations of what’s

out there

the second idea is that those best

interpretations

are the product of unconscious processes

that take around

half a second to complete and thirdly

choice is an illusion and our decisions

to act

are in reality our experiences

of unconscious processes that happened

and have already determined

our behaviors before i get into

exploring these questions

or these ideas in some detail i’d like

to just

go have a reality check there’s no

light or sound inside our heads

inside our heads is a dark and silent

space

what there is inside our heads is 80

billion neurons

these 80 billion neurons are each

individually connected

on average to 7 000

of their colleagues so that means

there’s approximately

560 trillion connections

in our brains so-called synapses

and this 560 trillion synapses

are organized in such a way that we have

specialist regions

in our brains connected by neural

pathways

some of these neural pathways are

microscopic just a few neurons thick

and other ones are fibers as thick as

our fingers that connect the major

regions of the brain

and all of these connections and all of

these specialist regions make up what we

call today

the human connectome if it’s if you like

it’s the ordnance survey map of our

brain

and it’s the pattern of activity in our

connect homes

that is actually giving us our

experience of what’s happening

right here right now

so with reality check out the way let’s

look at our first

uh idea your experiences of the world

are your individual best estimates of

what’s actually out there

now there’s over the last 20 years or so

there’s been a growing body of evidence

that fully supports this idea

but the scope of this talk isn’t going

to allow me to

go too deep into that and there’s some

pretty complex ideas in there as well

but what this talk will do is allow me

to do a couple of simple demonstrations

so please enjoy right firstly i would

like those members of the audience that

have a birthday

that begins with an even number to close

your eyes

and to keep them closed until further

notice

those of you with your eyes open i’d

like you to take a look at the following

image

right so those with eyes closed please

open them

and now we’re going to reverse the

process those of you with birthdays on

an odd number please close your eyes now

until further notice

and those of you with your eyes open

take a look at this image

right everybody with their eyes open

again now please

i’m now going to present an image and

i’d like you to make a note of the first

thing you

you see in this image

now some of you the first thing you’re

going to see in this image is a face

a face with spectacles others of you are

going to see a rat

or a mouse so what’s that about because

what we’ve done

here is we’ve created an audience in

which some people are seeing

a face and some people are seeing a

mouse or a rat

so you’re all making different

interpretations of what’s out there

now this demonstration is based on a

1960s study by bergelski and olampe

their so-called ratman experiment

and as you can see from the two images

what they found

significantly was that people had been

primed with a picture of a face

saw a face and those that had been

primed with a picture of a rat

saw a rat and this is what’s called

so-called

cognitive priming so this is my

initial demonstration to say to you that

what you’re seeing is your best

interpretation of what’s out there

and in this instance it’s based on an

earlier experience you had

so we can all be seeing something

different

now it’s not only cognitive priming that

establishes

what our interpretations are of what’s

out there

look at these next two images

so as i look at these images the image

on the left

is labeled a i see as the happier of the

two faces

um i’m guessing many of you would share

that the one on the left looks the

happier one

for other people the one on the right

labeled b

is going to be the happier face for

others you may

see not a happy or a sad face but you

may see two sarcastic faces or you may

see something

entirely different but uh the point i

make here is again

we’re interpreting the moods or the

emotions on faces

differently now what might be causing

this there’s no cognitive priming going

on this time around

but as i look at it and i think you know

face a is the happier face

maybe that’s got something to do with

the fact that my left eye

is my leading eye it may be something to

do with the fact that

i’m right-handed and that may be genetic

alternatively it may be something to do

with being brought up in a culture

where i i read from left to right

there’s many things in there that could

be influencing this but the point i want

you to take away from this part of the

talk

is that we’re all interpreting the world

according to our own

best interpretations idea number two

these best interpretations are the

result

of unconscious processes that take

around half a second

to complete so can i go back to the

reality check for a moment

there’s no light or sound inside our

heads

what there is is 80 billion neurons 560

trillion

synapses or connections

and there’s also chemistry and biology

there’s also anatomy and physiology

so that’s what’s going on in here

creating for me

this multi-colored

multi-sensory three-dimensional universe

that i’ve got in my head

is being created by just these things

no light i sound in my head regardless

of what it feels like

so what is going on here

well as i start to look out at the world

and i can just see the river thames

outside there

what’s happening is my eyes are

receiving various wavelengths of light

those wavelengths of light are being

coded into electrical signals

by the neurons the neurons are passing

on signals to other neurons

electrical signals going to my brain

in addition what i’m hearing is

picked up from pressure waves in the air

and those pressure waves through the

mechanisms in my ears

are being converted into electrical

signals

that are being passed onto other sig

onto other neurons

and ultimately into my brain

and these signals are all creating what

i’m going to call the primary processing

and this primary processing for my

visual system is turning those

electrical impulses

into colors and shades

and shapes primary processing processing

the inputs

from the outside for my ears much the

same sort of thing

it’s tone it’s volume um

it’s intonation of a voice

these are all the things that are coming

into my brain to my auditory cortex

primary processing

and i argue that primary processing

takes a finite amount of time

and i think it’s going to be taking

around 150 milliseconds

those primary processes then become the

inputs

into the secondary processes and this is

where the journey starts to get really

interesting

because the primary processes are now

being put together

with the stored knowledge i’ve already

got

so for example as i look out the window

and i see the particular shapes of a

river

i’ve got experiences of rivers in fact

i’ve got experience of that particular

river the river thames

i got memories about it from when i was

young i’ve got memories about it from a

few years ago when i was with my

children going along to greenwich

all of these memories are coming in to

meet in this secondary processing

something that’s helping me to interpret

what’s out there i interpret a river

my knowledge of rivers comes to bear

that particular river

my memories from my episodic memory come

to bear

so all this top-down processing goes on

it gets even more interesting yet again

when we talk about my auditory

processing

because not only am i hearing sounds but

i’m also

interpreting these sounds into words the

words

have to be built into sentences i have

to understand the grammar

from previous learning and that grammar

and the syntax has meaning for me

if you talk to me about new york i’ve

got memories of new york that have

meaning for me it’s not just the word

new york so all of this

processing is taking i’m going to argue

another 150 milliseconds

then even more magic happens because all

of that processing

then gets broadcast to my whole brain

into what’s called the global workspace

and it’s at this point that my conscious

awareness

and my interpretations of what’s

happening start to become life for me

now that’s pretty amazing now

auditory processing takes a certain

amount of time

visual processing takes a certain amount

of time

and they don’t take the same amount of

time so why is it that i don’t

experience the world like

a desynchronized and unsynchronized

video i don’t experience

that i experience everything lined up

beautifully

what’s more i don’t experience

everything as if it happened half a

second ago

i experienced it as if it happened now

so all of these processes are being

synchronized

within processes underneath the global

workspace

and being backdated so that i’m

experiencing this here and now

one more bit and this is the real magic

for me

not only have i created this entire

world out there

inside my head my own virtual reality my

own

super high definition movie but i’m also

creating

the main character in that movie

that’s the character i call myself and

i’m guessing it’s the same for you guys

but i can’t be absolutely sure of that

the third idea

choice is an illusion and

our experiences of decisions

are more realistically our experiences

of unconscious processes

that have already determined our

behaviors

here we see daniel libit as a young

scientist

uh in the early early 1980s i was

originally a microbiologist

i stumbled across this paper and

i’m going to just read you the title

time of conscious intention to act

in relation to onset of cerebral

activity

is the second part the unconscious

initiation

of a freely voluntary act now that

intrigued me that caught my attention

the

unconscious initiation of a freely

voluntary act

now there’s a contradiction in there

isn’t there a freely

voluntary act with an unconscious

initiation so i read the paper

absolutely fascinating what libit did is

a series of experiments

in which he asked people to listen to a

tone

wire up their heads wide up their

fingers wide up everything

and when they had a rare tone they had

to twitch their finger

and from the knowledge of the areas of

the brain that were active at different

points in time

and doing this experiment thousand doing

this demonstration thousands of times

he was able to average out and work out

what was going on in the brain

now if we call time zero the point at

which

a finger is twitched 550

milliseconds before that point there was

activity detected in the motor cortex

in other words the motor cortex was

initiating

that act 550 milliseconds before it

actually became a reality

350 milliseconds later

that part of the brain that is

associated with our conscious awareness

started to come into action 200

milliseconds later the action happened

so what’s this saying it’s not saying i

think

and then i do it’s saying i do and then

i think

and then it happens this is the

so-called user illusion

now libya got quite uncomfortable with

this idea and he did lots of other

experiments where it wasn’t about

responding to a single um to a single

sound

but rather his subjects were asked to

just whenever they wanted to twitch

their finger

same measurements done and some really

interesting stuff it was a lot more than

half a second

before the action that the readiness

potential was being created

in the motor cortex so

he then tried to do some other

experiments as he got older

and what he introduced the idea of was

free won’t

the idea that whilst we might not have

free will

we do have free won’t in other words i

don’t have to do

what my motor cortex has directed me to

do

but i’ve got a problem with that because

surely if i’m making a decision

to not do something that’s already

started that decision decision itself

had to start at a point earlier on

and as biological psychologists would

say

everything psychological is at first

biological

so libit’s extra experiments weren’t

able to convince me

but i’m approaching the end now we’ve

covered the three ideas so i’d just like

to leave something with you

if it’s true that our experiences of the

world

are our individual best estimates of

what’s out there

and those interpretations of what’s out

there

are the result of unconscious processes

that take

half a second to complete

and the choice is a free will and in

fact

our decisions are in reality our

experience of unconscious processes that

have already determined our behaviors

how could we be anywhere other than

right here

right now thank you