Tag: Human brain

The scent of danger.

A reflection on our reptilian brains.

Now of all the things I am not, I am neither a biologist nor a scientist of any description.  However, general knowledge told me years ago that the human brain is composed of three areas, as the following diagram shows.

The constituents of the human brain.
The constituents of the human brain.

A quick web search brings up THE EVOLUTIONARY LAYERS OF THE HUMAN BRAIN, from which I quote:

The first time you observe the anatomy of the human brain, its many folds and overlapping structures can seem very confusing, and you may wonder what they all mean. But just like the anatomy of any other organ or organism, the anatomy of the brain becomes much clearer and more meaningful when you examine it in light of the evolutionary processes that created it.

The most efficient model for understanding the brain in terms of its evolutionary history is the famous triune brain theory developed by Paul MacLean. According to this theory, the following three distinct brains emerged successively in the course of evolution and now co-inhabit the human skull:

The reptilian brain, the oldest of the three, controls the body’s vital functions such as heart rate, breathing, body temperature and balance. Our reptilian brain includes the main structures found in a reptile’s brain: the brainstem and the cerebellum. The reptilian brain is reliable but tends to be somewhat rigid and compulsive.

The limbic brain emerged in the first mammals. It can record memories of behaviours that produced agreeable and disagreeable experiences, so it is responsible for what are called emotions in human beings. The main structures of the limbic brain are the hippocampus, the amygdala, and the hypothalamus. The limbic brain is the seat of the value judgments that we make, often unconsciously, that exert such a strong influence on our behaviour.

The neocortex first assumed importance in primates and culminated in the human brain with its two large cerebral hemispheres that play such a dominant role. These hemispheres have been responsible for the development of human language, abstract thought, imagination, and consciousness. The neocortex is flexible and has almost infinite learning abilities. The neocortex is also what has enabled human cultures to develop.

These three parts of the brain do not operate independently of one another. They have established numerous interconnections through which they influence one another. The neural pathways from the limbic system to the cortex, for example, are especially well developed.

I’m well into reading the book Waking The Tiger: Healing Trauma authored by Peter A. Levine.  As early as Chapter One, Peter Levine explains [my emphasis]:

The involuntary and instinctual portions of the human brain and nervous system are virtually identical to those of mammals and even reptiles. Our brain, often called the ‘triune brain,’ consists of three integral systems. The three parts are commonly known as the ‘reptilian brain’ (instinctual), the ‘mammalian or limbic brain (emotional), and the ‘human brain or neo-cortex’ (rational). Since the parts of the brain that are activated by a perceived life threatening situation are the parts we share with animals, much can be learned by studying how certain animals, like the impala, avoid traumatization. To take this one step further, I believe that the key to healing traumatic symptoms in humans lies in our being able to mirror the fluid adaptation of wild animals as they ‘shake out’ and pass through the immobility response and become fully mobile and functional.

Unlike wild animals, when threatened, we humans have never found it easy to resolve the dilemma of whether to fight or flee. This dilemma stems, at least in part, from the fact that our species has played the role of both predator and prey. Prehistoric peoples, though many were hunters, spent long hours each day huddled together in cold caves with the certain knowledge that they could be snatched up at any moment and torn to shreds.

Anyway, to get back to what triggered today’s post.

If you read yesterday’s post you will recall me chatting with Jon Lavin and Jon reminding me that humans are drawn to positive messages.  But in stark contrast, the news media industry excels in promoting ‘doom and gloom’.  Why is this?  Why are we so fascinated by danger?

Well here’s my theory.

That is our evolution would not have succeeded if early man didn’t become pretty smart at identifying animal behaviours and plants and fruits that had the capacity to harm or even kill.  For example, what parent hasn’t made it a priority to teach their children the difference between harmful fungi and edible mushrooms.  Indeed to the extent that most of us would think long and hard before eating any fungi found in the wild unless we were 150% certain it was edible.  Look at the following picture.  Your instinct tells you if it’s safe to eat or not – it’s not!

Amanita muscaria photo © Michael Wood
Amanita muscaria photo © Michael Wood

So early man became over-sensitised to dangers to his health for his own good and continued existence. While modern man functions in ways almost unrecognisable from early man, that good old reptilian brain still is doing it’s best to protect us (flight, fight or freeze).  Think how we all respond to a sudden alarming sound, such as a gun shot or a scream, to know that the old reptilian brain is still alive and well.

Thus while all of us hate negativity we all seem to have this fascination with doom and gloom – just in case it helps us and our loved ones survive.

Back to Jon Lavin.  He makes it very clear that anything more than a small amount of ‘doom and gloom’ speaking to our consciousness increases the odds of depression and introversion.

Thus the message is that we humans should allow our Neocortex to tell our Reptilian ‘neighbour’ to go easy on the bad news, go and open a beer and watch the world go by! Whoops! Watch the world go by with a smile!

Oh, and Happy Valentine’s Day to you all.

The knowing of dogs.

A fascinating study on human empathy strikes a chord with man and dog, perhaps.

Let me start with a true account from the evening of Monday, 19th August.

That evening, at 7pm, I had an appointment with my doctor in Grants Pass.  Jean stayed at home looking after our guests and preparing the evening meal.

The journey from the doctor’s clinic back to home, a distance of 20 miles, takes a little over half-an-hour.  The last 3 miles are along Hugo Road; about 6 minutes including opening and closing the gate across our driveway.

Anyway, according to Jean shortly after 8pm Pharaoh sprang up barking and went across to put his nose against one of the windows that looks out over our front drive and garden.  Jeannie looked at the clock on the kitchen wall and made a note of the time: it was 8:10pm.  She also came over to the window that Pharaoh was looking out of and searched for any reason for his outburst of barking: squirrels, deer, any kind of wildlife or other distraction.  There was none.

A little before 8:20pm Jeannie saw the headlights of my car pull up and moments later I came in through the front door.

It appeared that Pharaoh had sensed the point where I had turned into Hugo Road.

One could easily dismiss this, perhaps by thinking that Jean had unconsciously signalled to Pharaoh that I was on my way home.  But Jean had only the vaguest idea of when I might be back.

Or one could be drawn to the research undertaken by Dr. Rupert Sheldrake, as this extract from a post back in May, 2011 explains.

What an amazing book this is.

Amazing!

I have written about Dr Rupert Sheldrake a few times on Learning from Dogs for pretty obvious reasons!  You can do a search on the Blog under ‘sheldrake’ but here are a couple of links.  Serious Learning from Dogs on January 10th, 2011 and Time for a rethink on the 14th April, 2011.

Anyway, I am now well towards the end of Sheldrake’s revised book, Dogs That Know When Their Owners Are Coming Home and it is more than fascinating.  Bit short of time just now so please forgive me if I do no more than show this video which sets out some of the background to the book.  Sheldrake’s website is here, by the way.

Anyway, what’s this all leading up to?

I can’t recall where it was that I read about a report posted on the Forbes website about the new findings of the power of human empathy.

Study: To The Human Brain, Me Is We

A new study from University of Virginia researchers supports a finding that’s been gaining science-fueled momentum in recent years: the human brain is wired to connect with others so strongly that it experiences what they experience as if it’s happening to us.

This would seem the neural basis for empathy—the ability to feel what others feel—but it goes even deeper than that. Results from the latest study suggest that our brains don’t differentiate between what happens to someone emotionally close to us and ourselves, and also that we seem neurally incapable of generating anything close to that level of empathy for strangers.

The research revealed:

“The correlation between self and friend was remarkably similar,” said James Coan, a psychology professor in U.Va.’s College of Arts & Sciences who co-authored the study. “The finding shows the brain’s remarkable capacity to model self to others; that people close to us become a part of ourselves, and that is not just metaphor or poetry, it’s very real. Literally we are under threat when a friend is under threat. But not so when a stranger is under threat.”

The findings back up an assertion made by the progenitor and popularizer of “Interpersonal Neurobiology,” Dr. Daniel Siegel, who has convincingly argued that our minds are partly defined by their intersections with other minds. Said another way, we are wired to “sync” with others, and the more we sync (the more psycho-emotionally we connect), the less our brains acknowledge self-other distinctions.

Later in that Forbes article Professor Coan is reported:

“A threat to ourselves is a threat to our resources,” said Coan. “Threats can take things away from us. But when we develop friendships, people we can trust and rely on who in essence become we, then our resources are expanded, we gain. Your goal becomes my goal. It’s a part of our survivability.”

So if science is discovering that our subconscious minds are connecting “psycho-emotionally” with the minds of others whom we trust, then it doesn’t seem like too great a leap to embrace human minds psycho-emotionally connecting with the animals that we trust, and vice versa.  Because for thousands upon thousands of years, the domesticated dog and man have depended on each other for food, protection, warmth, comfort and love.

Footnote.

References for those who wish to follow up on this article are:

Original Forbes article, written by David DeSalvo.

David DeSalvo’s website.

Daniel J. Siegelclinical professor of psychiatry at the UCLA School of Medicine and Executive Director of the Mindsight Institute.

Daniel Siegel’s book The Developing Mind.

Professor Robin Ian MacDonald Dunbar, British anthropologist, evolutionary psychologist and a specialist in primate behaviour.  His theory known as Dunbar’s Number explained here.

Oxford Journal: Familiarity promotes the blurring of self and other in the neural representation of threat.

Essence of wisdom, page one.

By three methods we may learn wisdom: First, by reflection, which is noblest; Second, by imitation, which is easiest; and third by experience, which is the bitterest.

Thus spoke Confucius, albeit not in the English language!  But, nonetheless, those words from so, so long ago (he lived to the age of 73 – from 551 until 479 BCE) resonate very strongly 2,500 years later.

That was the easy bit!

I’m not entirely clear as to why a variety of items that have crossed my ‘in-box’ in recent days seem to offer some sort of cohesive sense.  But they do to me and I’m going to draw them together. I will leave you to be the judge as to how well it worked!

Thus over the next three days I am going to reflect on three topics.  The challenge of how we humans make sense of the world, how we confuse what we do with what is best for us, surely the essence of wisdom, and the growing gap between the wisdom of millions of citizens and their leaders.

I should quickly add that much of my musings are due to this scribe standing on the shoulders of giants than seeing clearly from his own level.

Today, I shall start with the brain. Your brain, my brain, the brains of humans.  The reason this trilogy starts with the brain is that, ultimately, everything we humans think, feel and do comes from this brain of ours.  Our brain is who we are.

Let me offer you this video made by Bristol University in England.  Just a little over 6 minutes long it sets out the functional story of our brain.

(An animated tour around the human brain commissioned for Brain Awareness Week in 2010)

But there is so much more to this ancient body organ.

The Big Think website has been publishing a series called The 21st Century Brain. The latest episode published on November 6th was called Consciousness: The Black Hole of Neuroscience.  It starts thus:

What’s the Big Idea?

“By the word ‘thought’ (‘pensée’) I understand all that of which we are conscious as operating in us.” –Renee Descartes

The simplest description of a black hole is a region of space-time from which no light is reflected and nothing escapes. The simplest description of consciousness is a mind that absorbs many things and attends to a few of them. Neither of these concepts can be captured quantitatively. Together they suggest the appealing possibility that endlessness surrounds us and infinity is within.

But our inability to grasp the immaterial means we’re stuck making inferences, free-associating, if we want any insight into the unknown. Which is why we talk obscurely and metaphorically about “pinning down” perception and “hunting for dark matter” (possibly a sort of primordial black hole). The existence of black holes was first hypothesized a decade after Einstein laid the theoretical groundwork for them in the theory of relativity, and the phrase “black hole” was not coined until 1968.

Likewise, consciousness is still such an elusive concept that, in spite of the recent invention of functional imaging – which has allowed scientists to visualize the different areas of the brain – we may not understand it any better now than we ever have before. “We approach [consciousness] now perhaps differently than we have in the past with our new tools,” says neuroscientist Joy Hirsch.

Later on is this:

So there’s no reason to assume that consciousness is eternally inexplicable. However, it may never be explained through neurobiology, says David Chalmers, the philosopher who originally made the distinction. “In so many other fields physical explanation has been successful… but there seems to be this big gap in the case of consciousness,” he says. “It’s just very hard to see how [neurological] interactions are going to give you subjective experience.”

The fascinating essay concludes:

It’s no different than any other aspect of the brain that we cannot presently explain, she [Hirsch] says:

For example, we don’t understand how the brain creates colors. That’s a perception that is very private – I don’t know that your perception of blue is like my perception of blue, for example. Smells are another one. I don’t know that your perception of the smell of an orange is like mine. These are the hard problems of neuroscience and philosophy that we haven’t made a great deal of progress on.

What do you think? Is the distinction between “hard problems” and “soft problems” useful, or reductive? Does the brain create consciousness? Will we ever empirically understand where it comes from or how it works?

But it was one of the comments to the piece that jumped off the screen at me. From Beatriz Valdes and slightly edited by me, the comment offered:

Human consciousness happens in the human brain.  The human brain’s functions are rooted in what the human senses relay to it.  Self consciousness, consciousness of what is around us, is the result of thinking.  There would be no thoughts if the brain were a tabula rasa (Latin for blank slate), had no input from the senses. Therefore, consciousness is quite local, quite mortal, quite dependent on the gray matter inside our skulls.

Local and mortal.  Very profound (I think!).

So, if you like me suffer from time to time from understanding oneself, don’t worry.  There are plenty of others – aren’t there?  As Professor Dan Dennett makes it all clear below.

Philosopher Dan Dennett makes a compelling argument that not only don’t we understand our own consciousness, but that half the time our brains are actively fooling us.

Philosopher and scientist Dan Dennett argues that human consciousness and free will are the result of physical processes and are not what we traditionally think they are. His 2003 book Freedom Evolves explores the way our brains have evolved to give us — and only us — the kind of freedom that matters.

Good, glad that’s all clear. 😉

Stay with me for ‘page two’ of Essence of wisdom coming out tomorrow.