the mind-body debate. mind-brain debate what is the relationship between mind and brain?

The Mind-Body Debate

Mind-Brain Debate

What is the relationship between mind and brain?

Mind-Brain Debate

We are in fact considering an extreme case of reductionism

Mind-Brain Debate

Reducing man to the component parts of consciousness

Neuropsychology

Neurophysiology

Biology

Psychologists generally

This involves:

Mind-Brain Debate

There is general agreement that the mind (i.e. consciousness) is a property of human beingness.

Without a brain, there can be

no mind!

Mind-Brain Debate How can the two be related?

The body (brain) has Weight, Shape, Density and Physical Existence in

time and space

But the mind has none of these!

Mind-Brain Debate

The Question is:

How can a non-physical entity (the mind)

Influence and produce changes in something physical (Brain/Body)

Mind-Brain Debate

Example: Consider the act of scratching your head

In strictly scientific terms, this should not be possible. It is a purely subjective decision.

It involves the philosophy of two different kinds of substance:-

Non-physical mind and physical body

Mind-Brain Debate

The event of scratching my head involves the idea of causation.

From a materialistic viewpoint that should be impossible

Descartes believed that in this case, mind influences body

Mind-Brain Debate

Bit of a problem, eh? However, Science (including psychology) cannot accept

philosophical dualism – it’s either one or the other, mind or body.

Mind-Brain Debate

There is an evolutionary perspective – what survival value is there in consciousness/mind?

No value – unless it can bring about changes in behaviour.

Subjective experience says – mind does affect behaviour – try scratching your head!

Mind-Brain Debate

We have evolved with minds.Biological evolution has been for survival

value. If species doesn’t survive it doesn’t evolve.

We can assume that mind and body have evolved together for some reason because we have survived!

Mind-Brain Debate

Two main theories

Dualism – mind and brain coexist

Monism – mind and brain are separate

Dualism theories

Descartes

Epiphenomenology

Interactionism

Psychophysical Parallelism

Descartes

Mind influences body through pineal gland

But Descartes believed body could not influence mind.

Descartes

Descartes

Humphrey (1992) disagrees with Descartes.

Philosophy of Pain

PAIN

My pain can hardly count as a physical event.

It is not part of the objective world.It is not physical

PAIN

From the fact that there is no accompanying brain activity, we could say that my brain-based pain belongs nowhere else than in the world of physical material. It is, after all, nothing other than a physical event.

So, my pain – that is, my experience of pain – depends wholly on brain activity.

PAIN

Problem: to explain how and why and to what end the dependence on the non-physical mind and the physical brain has come about.

Somehow, between neural transmission and experience, there is a conversion.

It is nowhere near being understood.

Epiphenomenologists

Mind influenced by brain – reverse to Descartes.

An Epiphenomenon is ‘an accompanying event’, outside the chain of causation.

Epiphenomenology

Epiphenomenologists

Behaviour is caused by direct brain action and consciousness is a sort of indicator that it is happening.

Yet the mind is not involved in the process.

Where have we heard that before?Behaviourism – radical behaviourism in

fact.

Interactionists

They believe the mind-body influence is two-way

A kind of Liberal Democrat of the Mind-Body philosophy

Interactionism

Parallelists

Believe that mind and body exist but separately.

No effects between them.

Sometimes called psychophysical parallelists

Psychophysical Parallelism

Monist Theories

Can be mentalist – towards the mind end of the spectrum, or materialist, towards the body end.

mentalist materialist

Mentalism or Idealism

Only mental phenomena involved

Humanistic Psychology

Materialism

Two types

Periphalist

Centralist

Materialism – Periphalist theories

The mind is reduced to behaviour Watson claimed that thought was really

reduced to subvocalisation – a delicate instrument could pick it up.

Logical behaviourism: I think it will rain is translated into behaviour

when you unroll your umbrella. The mind = behaviour + disposition to behave

Centralist Materialism

Mental processes are identified with purely physical processes in the brain.

This is the aim of Cognitive Neuroscience

Mind-Brain Identity

Centralist materialismTakes the view that mental processes

are purely physical processes.They are no more than chemical

reactions/physical states in the brainMental states are equated with mind

states

Mind-brain identity

Place (1956): Is Consciousness a Brain Process?

Attempt to identify structures in the brain which correspond to mental states

What about brain-dead?

Mind-Brain Identity

Eliminative Materialism

And this really is where cognitive neuroscience is taking over!

Attempt to replace psychology with neurophysiology

Mind-Brain Identity

Crick (1994)“You, your joys, your sorrows, your

memories and your ambitions; your sense of personality and free will, are in fact no more than the behaviour of a vast amount of nerve cells and their associated molecules”