Presentation on theme: "Are you your brain? Steven Rose"— Presentation transcript:
Are you your brain? Steven Rose
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.
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 1862
Three Neuro Decades 1990s – decade of the brain 2000s – decade of the mind 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)
And the reach of the neurosciences grows ever longer Neurolaw Neurowar Neuroeconomics Neuromarketing Neuroaesthetics Neuroeducation Neuroethics………. And neuroculture??
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 uncontested
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!
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 synapses
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’
19 th 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 phosphorus
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’
And some philosophers follow suit Churchland – neurophilosophy and ‘folk psychology’ Dennett – ‘consciousness explained’
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.’
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)
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’
Phrenology – external and internal
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, , 2008
Brain sites for everything Mathematical ability Romantic love Moral judgments Voting tendency Terrorist thoughts Psychopathy And of course consciousness
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 location
Romantic love, psychopathy – and a dead salmon
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 brain
So here’s a thought experiment Let’s invent a cerebroscope
The cerebroscope Detects the activity of every neuron in my brain millisecond by millisecond
The cerebroscope So it will interpret my brain activity as Steven reading this caption, giving this seminar?
Or will it?
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?
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?
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 embedded
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 think
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.’