Are you your brain? - PowerPoint Presentation

Slide1

Are you your brain?

Steven Rose

s.p.r.rose@open.ac.ukSlide2

St. Augustine’s Questions

How does the brain/mind encompass:

Vast

regions of space and time

Abstract

thoughts, numbers

The

idea of god

Logical

propositions and false

arguments

.Slide3

Brain versus Mind?

(Emily Dickinson, 1862)

The Brain - is wider than the Sky -

For - put them side by side -

The one the other will contain -

With ease - and you -beside

The Brain is just the weight of God

For - heft them - Pound for Pound

And they will differ - if they do

As Syllable from Sound

Emily Dickinson,

c

1862Slide4

Three Neuro Decades

1990s – decade of the brain

2000s – decade of the mind

2013 - EU announces €1 billion for a ‘human brain project’ to build a virtual brain through computer

simulation.

Obama announces BRAIN – a $3billion project tracking all the trillions of connections between nerve cells in the human brain (starting with mouse!) paid for by NIH, DARPA etc

Will help ‘epilepsy, depression, schizophrenia, autism,

dementia..stroke

, cerebral palsy….’ (and the military)

Slide5

And the reach of the neurosciences grows ever longer

Neurolaw

Neurowar

Neuroeconomics

Neuromarketing

Neuroaesthetics

Neuroeducation

Neuroethics

……….

And

neuroculture

??Slide6

The core assumption of modern neuroscience

Minds and consciousness are brain processes

To cure the mind one must cure the brain

But these claims are not uncontestedSlide7

Brains and Minds: Four philosophical propositions

Dualism: Body/brain …. Soul/mind two different types of stuff

Identity: Brain/mind are two aspects of the same phenomenon

Epiphenomenalism: Mind emerges from brain

Mechanical materialism: Minds are ‘nothing but’ brains

NOTE! I am not going to agree with any of these!Slide8

Not all neuroscientists have been hard materialists

Descartes and the pineal gland

Sherrington’s enchanted loom

Sperry’s downward causation

Eccles and the liaison brain – the god of

the synapsesSlide9

Some modern Dualists

Edelman – you are your brain.. plus

free will!

Libet

- the 350msec gap and the brain’s ‘free won’t’

And some closet dualists – Dawkins, Pinker

‘only we can rebel against the tyranny of our selfish genes

‘if my genes don’t like it they can go jump in the lake’Slide10

19th century materialists

Thomas Huxley: Mind is to brain like the whistle to the steam train

Moleschott

, Vogt et al: The brain secretes thought like the kidney secretes urine; genius is a matter of phosphorusSlide11

Modern materialists

Crick – ‘you are nothing but a bunch of neurons’

Kandel

– ‘you are your brain’

Silva – ‘ruthless reductionism’

Gazzaniga

– ‘the ethical brain’

LeDoux

– ‘synaptic self’

Changeaux

– ‘neuronal man’Slide12

And some philosophers follow suit

Churchland

–

neurophilosophy

and ‘folk psychology’

Dennett – ‘consciousness explained’Slide13

Some problems for materialists

Subjective experience and

qualia

– how does conscious experience emerge from brain chemistry/physics

How did consciousness evolve (Darwin

v

Russell Wallace)

Free will and determinism – ‘my brain made me do it.’Slide14

But if this were true

Minds wouldn’t matter at all – we only need think brains

But minds do matter; we have self-awareness; minds have reasons, are conscious and are evolved properties of humans, with Darwinian survival functions. These are irreducible properties.

So we also have to assume that although there is a qualitative jump between us and our nearest evolutionary relatives (chimps,

bonobos

) that these and maybe other big brained animals have rudimentary forms of consciousness (

Damasio

; Nagel)Slide15

fMRI promises to solve the mind/brain question

Brain

sites for every thought and feeling

‘

A happy marriage between

fMRI

and experimental psychology can bridge the divide between mind and brain’ Slide16

Phrenology – external and internalSlide17

‘Psychopathic Brains?’Slide18

The Right and the Good: Distributive Justice and Neural Encoding of Equity and Efficiency*

Subjects making decisions re allocating meals to children in Ugandan orphanage

Quandary

: to share limited food equally (equity) but inadequately, or giving enough food to chosen few (efficiency)

.

Result: ‘

Insula

encodes inequity,

putamen

efficiency

’

*Hsu et al

Science

320

, 1092-5, 2008Slide19

Brain sites for everything

Mathematical ability

Romantic love

Moral judgments

Voting tendency

Terrorist thoughts

Psychopathy

And of course consciousnessSlide20

NeuroloveSlide21

So what’s the problem?

Overestimates the power of

fMRI

Blood flow surrogate measure

Timescale (seconds )too long

Volume too great :50mm

3

contains

5m neurons, 50b synapses 22km dendrites, 220km axons!

Mistakes activity for locationSlide22

Romantic love, psychopathy

– and a dead salmonSlide23

But there are more fundamental problems

These studies reify processes, thoughts and

judgements

– turning concepts from the social realm (efficiency, terrorism,

psychopathy

..) into

localisable

‘things’ in the brainSlide24

So here’s a thought experiment

Let’s invent a

cerebroscopeSlide25

The cerebroscope

Detects the activity of every neuron in my brain millisecond by millisecondSlide26

The cerebroscope

So it will interpret my brain activity as Steven reading this caption, giving this seminar? Slide27

Or will it?Slide28

A more dynamic cerebroscope

Not only reads the present state of my synapses but has plotted them millisecond by millisecond from their formation.

So could you now ‘read off’ my mind from my brain?Slide29

I still think the answer is no

The experience may impose a unique pattern in my synapses etc, but can that pattern in turn be read as unique to the

experience?

The pattern may show I am talking, but will it show the

content

of my speech?

Slide30

Because

There’s more to the brain than wiring diagrams and neurotransmitters

Modulators, field effects etc

The brain is in the body

hormones, immune system

But more fundamentally:

brain and body are part of the biosocial world in which we are embeddedSlide31

Minds are not Brains

Minds are to brains like legs are to walking.

We don’t say ‘my legs are walking’ but that

we

use our legs to walk

Similarly, it is

we

who have minds and consciousness, and

we

use our brains to thinkSlide32

Nor are our minds in our bodies (as St Augustine suggested)

Maybe as philosopher Gilbert Ryle suggested we don’t

have

minds (noun); instead we

mind

(verb).

Minding is a hybrid, not a reified brain process, though it requires the brain, but an ever-changing relationship between an individual and the physical social cultural and historical world;

Consciousness is relational, the dynamic product of present and past brain and body activity, life history and social context, a

process

, not a reified ‘thing.’