Conscious Experience and Brain Activity

extract from Rupert Sheldrake, The Science Delusion

“Many philosophers have speculated about the relationship between the mind and the brain, but the neuroscientist Benjamin Libet and his team in San Francisco investigated it experimentally by measuring changes in the brain and the timing of conscious experiences.

First, Libet’s group stimulated their human subjects either by flashes of light or by a rapid sequence of mild electric pulses applied to the back of the hand. If the stimulus was short, less than about half a second (500 milliseconds), the subjects were unconscious of it, even though the sensory cortex of their brains responded. But if the stimulus went on for more than 500 milliseconds, the subjects became consciously aware of it. So far, so good. The need for a minimum duration of stimulus is not in itself surprising. What is surprising is that the subjects’ conscious awareness of the stimulus began not after 500 milliseconds but when the stimulus started. In other words, it took half a second for the stimulus to be experienced subjectively, but this subjective experience moved backwards to when the stimulus was first applied. ‘There is an automatic subjective referral of the conscious experience backwards in time.. The sensory experience would be “antedated” from the actual delayed time at which the neuronal state becomes adequate to elicit it; and the experience would appear subjectively to occur with no significant delay’.

Second, Libet investigated what happened when people made free conscious choices. Eh measured the electrical activity of their brains by means of an electroencephalograph (EEG), with small electrodes placed on the surface of the head. The subjects sat quietly, and were asked to flex one of their fingers or push a button whenever they felt like doing so. They also noted when they decided or felt the wish to do so. This conscious decision occurred about 200 milliseconds before the finger movement. This seems straightforward – the choice preceded the action. What was remarkable was that electrical changes began in the brain about 300 milliseconds before any conscious decision was made. These changes were called the ‘readiness potential’.

Libet .. suggested that in the time between conscious awareness of the desire to act and the actual movement – a gap of 200 milliseconds – there was an opportunity for the person’s mind to veto the decision. Instead of free will, we have ‘free won’t’. This conscious decision depended on what Libet called a ‘conscious mental field’ (CMF), which emerged from brain activities but was not itself physically determined by them. The CMF acted on the activities of the brain, perhaps by influencing otherwise random or indeterminate events in the nerve cells. This field also helped integrate the activities of different parts of the brain and had the property of ‘referring back’ subjective experiences, and thus worked backwards in time.

Granular time?

Physicists say that matter is granular. Made up of tiny bits. Digital not analogue or seamless. Or so it seems? Though they seem to smash matter into smaller and smaller digital pieces and describe the smallest pieces now with equations imputed from shadows of reactions in tiny amounts of time. There is a unit measure of space – named after Max Planck – below which as Heisenberg has proved – we cannot see or measure. I wonder whether matter might be a little bit slipperier than physicists would have it? Is it possible, just maybe, that it is their search for certainty that is trying to fit it into bits?

And time? What about time. Is there then a granular unit of time. After all – as Alfred North Whitehead showed – Reality is a Process. Time is involved, within, each bubble of reality. Where materiality and spirituality are time in different directions applied to the reality-moment – now. But think about it – reality is, as Whitehead has it in the moment NOW. He points out that quantum mechanics implies that matter is a wave and that waves can only exist with time within them. So that he connects reality through time. Through moments of NOW.  But how long is NOW? Is there a reality quotient, a kind of atom of time that defines what is NOW rather than future potential and past material? I have no sense of Whitehead’s kind of maths or philosophy. Indeed I only have a tenuous grasp of his thesis – and most of that through Rupert Sheldrake’s synopsis in his excellent – The Science Delusion.

But even considering the widely read Buddhist inspired book – The Power of Now – leads you to consider surely – How Long Exactly is NOW. Is there a unit of time that is Now?

Just a thought.

 

Mystical Ellipticism

Why are all the great thinkers difficult to understand, at least with our mind? Perhaps because reality is so difficult for us to perceive – as through a glass darkly. That wouldn’t be surprising I guess. Our brain is evolved to help our bodies survive in jungles. We don’t see polarised light as bees do. The point is – it’s not some kind of perfect instrument designed to understand the outer reaches and meaning of creation. Neither does it have complete sensory input.

At least for me, those who have most changed my life all point to reality in relation. That is to say – reality existing in the magnetism between two points. As opposed to reality in the points themselves,

Carl Jung, for instance, in his search for integration between opposites “The meeting of two personalities is like the contact of two chemical substances: if there is any reaction, both are transformed”. Martin Buber sets out his form of existentialism entirely against a backdrop of relationship – his “philosophy of dialogue” with it’s primary words I-Thou and I-It. Teilhard de Chardin saw the process of evolution (powered by love) toward a shared consciousness. Alfred North Whitehead saw the whole of reality as process.

All of these elliptical thinkers seem to expose facets of the same underlying truth. It’s connection that matters, not matter that connects.

And yet..

For the Dawkins of this world it’s so simple. Matter. Of Fact. Simple(s). Nothing there but things. Science, thought and our brains have solutions. Death comes and there is nothing beyond. Love, kindness, a shared smile – all just twitchings of the material – set in the one-way street of time.(It’s not what science shows, but there you are .. better read Rupert Sheldrake on the subject.)

The writings of Buddha, the parables of Christ, the music of Bach. Complex – difficult. Mystical. Elliptical.