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Archive for the ‘neuroscience’ Category

The great leap

Posted in books, education, from the dark room, from the living room, from the reading room, life, neuroscience, personal growth, psychology, science on May 10, 2014| Leave a Comment »

Diving for silver?

 

It seems we didn’t evolve into human beings in a smooth, seamless way, but more with a pattern of great leaps and long, slow changes.

One of these great leaps was in the growth of the size of the brain. One of our pre-human ancestors, Homo erectus,  had much smaller brains than we do, but over the course of 200,000 generations (2 million years), their brain size roughly doubled in size, taking them up to about the same size as brain as we humans have (since about 500,000 years ago).

As Stephen Oppenheimer states, rapidly increasing brain size was a key feature that set humans apart from the walking apes that lived before 2.5 million years ago. Since then our brains have trebled in volume. This increase was not gradual and steady: most of it came as a doubling of volume in Homo erectus 2 million years ago. The greatest acceleration in relative brain size occurred before 1.5 million years ago – early in our genus. Modern humans – and Neandrathals – living before the last ice age 20,000 to 30,000 years ago had bigger brains than do people living today. (from)

Interestingly, brain size in humans hasn’t increased over the last half million years (indeed it’s shrunk a bit!), but what has happened is rapidly increasing asymmetries in the brain. It’s not just that our massive cerebral cortexes are asymmetrical, but within each area of the brain there are highly specialised areas. In other words, its a story not just of an increase in size, of adding more and more neurones, but of complexity.

Here’s one of the puzzles about evolution though – how on Earth did brains evolve so quickly? You might say 2 million years doesn’t seem that quick but look at the speed of change.

cerveau_evolution

 

This is why some people refer to the growth of the human brain as the second “Big Bang”…….although I do like the idea of a “Great Leap”!

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Who are you?

Posted in books, from the living room, from the reading room, life, neuroscience, personal growth, philosophy on May 1, 2014| 1 Comment »

It’s very common for us to say something like “My head is sore”, or “My stomach aches”, or even “I have a rash” when we experience one of those symptoms. So who is it who has this head, stomach or rash? This way of talking confirms our feeling that we “have” a body, but that our bodies are not us. Stop and think about it for a moment. Are you your body?

You might answer that your body is part of you but it isn’t YOU. That the you who has this body is maybe your mind?

But then we do the same thing with our minds too, don’t we? We say “I’ve lost my mind”, or “I’m out of my mind with worry”. Who is the “I” who is referring to this mind?

So your body isn’t you. Your mind isn’t you. But both your mind and your body are a part of you.

The physicalist approach to this claims that this “you” which you experience is an illusion. It’s just something your brain makes up.

But stop and think about that one for a moment. If “you” are an illusion, who is having this illusion?

This is what Mary Midgley is exploring in her latest book, “Are you an illusion?”

I highly recommend you read it. It’s short, and it’s an easy but deeply thought provoking read.

She asks of those who write the books claiming that only the physical is real, and that the subjective sense of self is an illusion

Unkind observers sometimes enquire who, in that case, actually writes the books that expound this doctrine? Do the brain cells really do this work on their own?

She quotes the neuroscientist, Susan Greenfield, saying in an operating theatre, “This was all there was to Sarah, or indeed any of us…..we are but sludgy brains” and Colin Blakemore saying “The human brain is a machine which alone accounts for all our actions” and she responds

Thus if we want to understand why (for instance) Napoleon decided to invade Egypt or Russia, what we need is not – as we might think – some knowledge of the political background and of Napoleon’s state of mind, but simply facts about the state of his brain, which alone can account for his action.

Does the claim that you are only your brain cells, or only your DNA, ring true for you?

The materialist credo rules that thoughts, not being physical, cannot cause physical events. And as we know from every activity of our lives that thoughts actually can and do affect those events – that they are often all too effective, producing practical results in the world even when we wish they wouldn’t – this doctrine puts materialism into a radical conflict with reality.

This is the nub of it for me. These materialist beliefs don’t only not ring true, they don’t adequately explain reality. So why are they so prevalent? One of the authors she draws on to answer this is Iain McGilchrist who has shown us how the left and right hemispheres of the brain work together to produce and integrated understanding from their two very different ways of approaching reality. She quotes him saying

Mind has the characteristics of a process more than of a thing; a becoming, a way of being rather than an entity

This is almost identical to the way Dan Siegel and the Interpersonal Neurobiologists put it – “the mind is a process of regulation of energy and information flow”.

She hits the nail on the head time and again. Let me finish with this one

The bizarre anti-self campaign which is the main subject of this book is surely intended, among other things, to put us off taking notice of everybody’s inner life: to persuade us that this is a trivial, contemptible subject by the simple device of pretending that it isn’t there.

 

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What can you fit a mind into?

Posted in from the living room, from the reading room, life, neuroscience, personal growth on April 5, 2014| Leave a Comment »

In the wonderful “The Republic of Tea” Mel says

The whole problem with Western civilisation is that ever since the Greeks we’ve been trying to squeeze the mind into the brain and it won’t fit.

Wonderful!

My first thought was Alva Nöe’s point in “Out of our Heads” – “Brains don’t have minds, people do”

Then I recalled Dan Seigel’s definition of mind as being an “embodied inter-relational process of regulation of energy and information flow” – which certainly doesn’t fit the mind into the brain!

Andy Clark talks about the “extended mind” in his “Supersizing the Mind” –

According to BRAINBOUND, the (nonneural) body is just the sensor and effector system of the brain, and the rest of the world is just the arena in which adaptive problems get posed and in which the brain-body system must sense and act.
Maximally opposed to BRAINBOUND is a view according to which thinking and cognizing may (at times) depend directly and noninstrumentally upon the ongoing work of the body and/or the extraorganismic environment. Call this model EXTENDED. According to EXTENDED, the actual local operations that realise certain forms of human cognizing include inextricable tangles of feedback, feed-forward, and feed-around loops; loops that promiscuously criss-cross the boundaries of brain, body and world. The local mechanisms of mind, if this is correct, are not all in the head. Cognition leaks out into body and world.

And then there was that recent map of body emotions which showed where we locate different emotions (certainly not just in our brains!)

But the mention of the brain-based focus of Western civilisation since the time of the Greeks producing such limits to our understanding, I couldn’t help thinking again of Iain McGilchrist and how I’m sure he’d say it’s not just that we’ve been trying to squeeze the mind into the brain, but that we’ve been tried to squeeze it into the left hemisphere!

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A whole brain is better than half a one

Posted in education, from the dark room, from the living room, from the reading room, life, neuroscience, perception, personal growth, science on March 26, 2014| 2 Comments »

IMG_0571

When I learned neuroanatomy at Medical School I was taught that the two cerebral hemispheres were symmetrical. There was no mention at all that they were in any way different. But look at this image above. (This is referred to as Yakovlevian Torque)

Clearly, the two hemispheres are NOT identical. In particular the right one is bigger at the front, and sits just a bit in front of the left, and the left one is bigger at the back, and sits just a little further back than the right.

Why might that be? Why the larger frontal area on the right, and occipital (back) area on the left?

Iain McGilchrist nicely summarises it by pointing out that how the left hemisphere approaches the world is by trying to grasp it. We try to make sense of the world by literally getting a hold of it – we want to understand it, to measure it, to predict what it going to happen by matching the patterns we see to those we have already learned from our experience, and we try to manipulate or control it. This is what the left hemisphere is really great at doing. Interestingly, the areas at the back of the brain are primarily for processing the outside world (our visual and auditory areas are toward the back, and the cerebellum which helps us to know whether we are standing up or falling over by orientating where we are in 3D space, is also to the back). The right hemisphere majors in making connections and maps. It has a significant role to play in all the skills we need to act as social animals.

So, one nice summary of why there might be this asymmetry in the brain, is to enable us to both grasp the world and to be social creatures. Amongst all the creatures on this planet we are probably the most able to manipulate our environment and the most developed as social animals.

There’s a huge amount more to this left brain/right brain understanding but I do think this is a fabulous starting point. Oh, and by the way, look at this

IMG_0349

Interesting, huh? And how come this has been pretty much completely ignored for so long?

Well, Iain McGilchrist’s theory, written up in full in The Master and His Emissary, or summarised in the Kindle Single, The Divided Mind, is that we have over developed the left hemisphere approach so much that we have developed the tendency to see only what we have already “learned” – so if we were taught that it was symmetrical, and we haven’t explored the differences between the two hemispheres, then we’ve become a bit blind. Time to start using our whole brains?

 

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Straight or round?

Posted in from the dark room, from the living room, from the reading room, life, neuroscience, perception, personal growth, photography, psychology on March 14, 2014| 1 Comment »

shadow of an empty seat

No straight lines are to be found in the natural world……..Leonard Shlain has pointed out that the only apparently straight line in the natural world is that of the horizon, but of course that too turns out to be a section of a curve……..Straight lines are prevalent wherever the left hemisphere predominates. Iain McGilchrist. The Master and his Emissary

playing under the moon

By contrast the shape that is suggested by the processing of the right hemisphere is that of the circle, and its movement is characteristically ‘in the round’, the phrase we use to describe something that is seen as a whole, and in depth. Iain McGilchrist. The Master and his Emissary

Circular rainbow

 

So, if the left hemisphere prefers straight lines, and straight lines don’t really occur in nature, and the right hemisphere prefers to see things in the round, then why not go out this weekend, and see how many round shapes you can see? Strengthen seeing with your right hemisphere!

lily pond

through the round window

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Half a brain…..

Posted in from the consulting room, from the viewing room, health, neuroscience, video on January 17, 2014| 3 Comments »

Take 20 minutes to watch this brilliant TED talk by Iain McGilchrist.

 

I agree with everything he says in this, but I was especially struck by his mention of the gene which codes for eyes. It’s the same gene which codes for a fly’s eye, a frog’s eye and a human eye. What makes the difference? The context of the other cells in the separate creatures. We are not just our genes, and our genes only express themselves in the contexts of the cells in which they exist.

I also really like what he says towards the end of the talk about protocols and the practice of medicine. How on earth can a protocol devised by a committee somewhere tell a doctor how to treat this particular, unique, individual patient today? It’s nonsense.

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MEAMs

Posted in from the music room, from the reading room, music, neuroscience, personal growth, psychology, science on December 18, 2013| Leave a Comment »

Hmmm…..haven’t come across this acronym before but its an exciting one!

It stands for Music Evoked Autobiographical Memories.

This interesting study used “No. 1 songs” to stimulate autobiographical memories in patients with brain injuries. They compared this method to the standard psychological “AMI” – Autobiographical Memory Interview. It’s a very small study of 5 patients and a very specific type of problem so the conclusion that music was more efficient than verbal prompts at eliciting autobiographical memory needs further study.

However, this whole idea has pricked my imagination. How often does a particular song or piece of music take you right back to a particular place, time or person in your life? How often do we share music with old friends or family to recreate our shared autobiographical memories?

One element of the study which is especially interesting is that most of the MEAMs were associated with positive emotions. When you think of our brain’s bias to negativity (Rick Hansen says our brains have velcro for negativity and teflon for positivity), and the common claim that we need a ratio of 3 – 5:1 positive to negative thoughts a day to experience flourishing, then surely music must be a GREAT tool for embedding positive, accessible experiences into our memories.

I know, there are lots of other reasons why music plays an important part in our lives, but, hey, MEAMs just sound such fun!

 

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poetry

Posted in books, creativity, from the dark room, from the living room, from the reading room, life, neuroscience, personal growth, photography, psychology on November 20, 2013| Leave a Comment »

Robert Burns statue

David Suzuki writes (in “The Sacred Balance”)

Definition identifies, specifies and limits a thing, describes what it is and what it is not; it is the tool of our great classifying brain. Poetry, in contrast, is the tool of synthesis, of narrative. It struggles with boundaries in an effort to mean more, include more, to find the universal in the particular. It is the dance of words, creating more-than-meaning, reattaching the name, the thing, to everything around it.

Iain McGilchrist, in his astonishing, “The Master and His Emissary“, describes the brain’s left hemisphere approach to the world as analytical, naming, classifying, analysing. And he cites poetry as one of the great functions of the right hemisphere’s way of engaging with the world. The right hemisphere “struggles with boundaries”, sees the connections, synthesises, holistically discovers “the universal in the particular”.

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How we see….making it up

Posted in creativity, from the dark room, from the living room, life, neuroscience, perception, photography on September 30, 2013| 1 Comment »

mucemreflect

When I was a little boy I thought that vision was like a kind of projector, casting images from the outside world up into my brain.

puddletrees

As I got a little older I thought the eye was like a prism, which would capture the outside view  and transmit it upside down onto the back of my brain, then my brain would flip the image back the right way up somehow.

Once I learned more about it I discovered that neither of those explanations are even remotely correct. In fact, (of course), light doesn’t pass through our eyes at all so they are not in the slightest like camera lenses, or prisms. What happens is that light stimulates special cells which line the insides of our eyeballs, and those signals are converted into electric/chemical signals which are sent through nerve cells to the “visual cortex” at the back of the brain – yes the back of the brain! Isn’t it odd that the back of the brain is the bit we use to see with?!

For a while I pretty much left it at that. But then as I learned more I discovered that vision is a MUCH more creative process than I’d considered so far. Not only is there a patch inside the eye which has no specialised cells for responding to light at all – in other words there is a “blind spot” in each eyeball which is incapable of seeing anything, but the visual cortex isn’t even a single part of the brain.

goldman

In fact, nobody has managed to completely map out just how our brains created the experience of seeing. The visual cortex is now considered in six separate areas of the each hemisphere (named V1 – V6) – that is 6 areas for each hemisphere, or 12 separate areas altogether to create our experience of a seamless image with no blind spots or missing bits. Some of those parts respond to movement, some to colour, some to shapes, some are wired to perception and some to actions……really, it’s too complex so far for us to fully grasp.

So, here’s what surprises me – each eyeball has a bit in it that doesn’t create the images we see – we call that bit the “blind spot” and it’s where the nerve cells which lead into the brain gather together at the back of the eye. Then each eye sends its signals to a complex of six different areas of the brain.

woman

And somehow, we weave together all those stimuli, and all those signals and computations to instantaneously create whole, seamless images. Amazing! Really, it’s astonishing.

So what do you think of these sculptures which were placed near to the town hall in Marseille?

bandana

travelcase

docker

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The meeting of the three lizard minds

Posted in from the dark room, from the living room, life, neuroscience, personal growth, photography on September 15, 2013| 1 Comment »

Meeting of the lizard minds

Well, these little guys got me thinking. They just sat there doing this motionless three way meeting thing in the sun.
I thought look at the three lizard minds meeting!
And of course that set me off on thinking about the three brains we each have, and how only one of them is a lizard mind! You know that model?
You can think of the human brain as having three distinct waves of evolution, each with its own main area of responsibility and each, intricately connected to the other two. We use all three all the time.
The oldest one is what people call the lizard brain. It’s the brain stem. The deepest and, in evolutionary terms, the oldest part of the brain. It’s the part at the top of the spinal cord and its all about survival. The autonomic nervous system spins out from here (its the accelerator and the brake system which produces, respectively, the fight or flight, and the rest and digest, responses to immediate threats. In fact those are the brain stem’s main duties – to control the heart rate, the breathing rate, the release of sugars and energy and so on. It’s our survival centre. It’s also involved in the production of emotions through its links to the second brain, the limbic system. Some people call the limbic system the mammalian brain, because mammals have it. It has a number of main tasks, primarily associated with memory processing, attraction, and the production of emotions. The big bit on the top, the cerebral cortex, split into left and right hemispheres, is the youngest part in evolutionary terms. It’s a great co-ordinator, analyser, synthesiser, map maker and thinker. This is the bit where we seem to get conscious thought from.
Ok, that’s a VERY simplified account, but I wanted to whet your appetite and hopefully make you curious to become more aware of what’s going on inside your head. We can learn to become more aware of these different areas and their processes and through their intimate two way massive links between each other, and between the brain and the body, we can begin to understand why it makes no sense to create a false model which posits that we can think of the brain and the body as separate. We can’t separate them. What goes on in one part affects all the other parts.
And how do we begin to claim we understand illness when we don’t understand yet what good mental and physical health is (I didn’t even like writing that last phrase because I just don’t think you can divide things between “mental” and “physical” that way)
The other thing I thought, in my meeting of the lizard brains rumination, was thank goodness we don’t have three lizard brains in our heads! Thank goodness, that instead, we have something much more complex, much more evolved, which allows us to experience the world in such unique and intricate ways. I do love uncovering some of the patterns in there by listening to people’s stories and seeing them in the contexts of their lives.
It’s an amazing world. Full of incredible creatures, all so inextricably connected in so many ways……I think we are only just beginning to realise that.

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