Recently, my brother told me a story about how he had met a man who had been diagnosed with a tumour in the middle of his brain, which was spiral in shape. Eventually the man found a surgeon who could remove it. The process involved opening the skull, cutting the two hemispheres of the brain apart (such “split-brain” operations were common for epilepsy decades ago), scraping out the tumour, and putting him back together again. According to my brother, the man has a made a very good recovery.
I wondered how someone could survive having their brain pulled apart so, and what this would mean for the man going forward. Anyway, I told my brother, the usual story that the left hemisphere is for language and is analytical, the right hemisphere is for visual imagery and is emotional, but I’ve since discovered this isn’t actually the case: that urban myth was falsified long ago.
However, I’ve been interested in this subject of left-right brain differences for some time, in particular after learning from Dr Joaquin Farias that in dystonics (people with movement disorders, including Parkinson’s Disease), the motor/physical symptoms correspond to a "cortical shock" in which the right hand pre-frontal cortex (usually) of the brain gets shutdown. So it seems there is still something to the left-right split, but if the old myths are not true, what is the real story, and how can this inform us about chronic conditions like PD?
I was therefore very intrigued to have synchronously been sent to a link by a friend to this video short, introducing me to the work of Iain McGilchrist, on this very subject. I have made some notes below the video about it, to help introduce the concepts and begin to explore why this could help unravel aspects and experiences of living PD.
The concept that one hemisphere (the left) does reason, the other (the right) does emotion is false, in fact, both are involved: anger is particularly left brained emotion, for example.
Ideas that language is only in the left, visual imagery in the right, are also false.
But brain functionality is divided, and the bit in the middle which is physically connected has actually got smaller over human evolution, even though the brain has got bigger.
The brain is also highly asymmetric, as if someone has twisted it clockwise.
Left brain: narrow focus attention, things all ready known, attention to detail.
Right brain: broad focus, vigilant for novelty, making connections with the world, sustained, open alertness.
Frontal lobes allow us to stand back from the moment, to manipulate and overcome adversaries or empathize, to be creative.
Left brain: manipulation of environment, using shorthands and abstractions - maps and patterns and categories, not reality, disposition for the mechanical, yields clarity and deals with the known, static, isolated, decontextualized, disembodied, lifeless.
Right brain: devils advocate, sees in context, big picture, understands individuals not just categories, empathy, social connection and bonding, disposition for the living, embodied, deals with the evolving, changing, interconnected, unknown.
Imagination and reason need both hemispheres: together they give knowledge of the parts and wisdom about the whole.
Western culture has become more and more unbalanced, more orientated to the left brain point of view, prioritizing the virtual and technical over the real. Left hemisphere controls the "media" of our internal voice, left talk very convincing, very vocal, right hemisphere doesn't have a competing internal voice and can't make same arguments. This imbalance is causing health and societal issues, more fragmentation, more emphasis on the represented rather than what is present, more emphasis on rhythm in music, compared to melody.
A full length version of Iain’s Divided Brain talk is also available.
Iain has also given a TEDex talk on this subject:
Implications for Parkinson’s Disease
I have since been considering what Iain McGilchrist’s “Divided Brain” work has to teach us, in the context of trauma and chronic illness, and seeking to employ both hemispheres of my brain in thinking about this. I began to see how Iain’s work provides us with a vital missing part of the puzzle. Indeed, his concept of the "Divided Brain", I now feel, connects so very many of the pieces, and I will endeavour to contexualize and map out my thinking on this here.
Some further clues came from the start of the presentation by Iain, where he mentions some anecdotal evidence:
"Teachers have noticed in the 5-10 years that they need to teach children how to read the human face."
"Emails from teachers in the last 3-4 years 25-30% of children can no longer do specific tasks which involved sustained attention span, whereas before virtually all children could do the same task"
"Research suggests that children are becoming less emphatic (social connection and identification with others)"
According to Iain, these are all principally governed by right hemisphere perspectives of the world. Issues with reading faces (also directly related to a person having inhibited or masked facial expression, or "blank face"), lack of social connectedness and empathy are huge parts of trauma, nervous system dysregulation and very many chronic illnesses, see
Indeed, these issues point directly to inhibition of the Para-Sympathetic Social Engagement nervous system, which Dr Stephen Porges' "Polyvagal Theory" makes clear is vital for health, restoration and growth.
Thus the seeds of profound connections between dysregulation, or inhibition, or lack of developmental of one of the hemispheres of the brain, particularly in the prefrontal cortex area, with trauma and chronic illnesses, are sown. We will explore these themes more broadly and deeply below and in Part 2. Most importantly, we will take what we can from Iain's teachings for pragmatic application to our healing and improved well-being.
I will seek to establish connections with the idea that one side of the cortex is "out of order" in traumatized and chronically ill people, thus skewing our thoughts, perceptions and connections with the world, ourselves and other people. I will endeavour to show how this explains types of behaviours and symptoms, and what the pragmatic applications of these links are.
Let’s begin with the work of Dr Joaquin Farias on dystonia. Dystonia relates to abnormal muscle tension and responses, which abound in many chronic illness, including Parkinson's Disease, but also are known to be amongst bodily memories which accompany trauma. Dystonias may occur in the hands, feet, neck, shoulder, face, stomach, limbs, or may be generalized throughout the whole body. Dr Farias has helped thousands of people around the world permanently reduce symptoms or recover from dystonias of all forms, due to his unique understanding of the condition, which as we will see, ties in directly to "The Divided Brain" concepts. Dr Farias' work is also covered in the additions to the paperback edition of Dr Norman Doidge’s book "The Brain's Way of Healing".
Dr Farias considers that dystonia is caused by re-emergence of Primitive Reflexes, automatic responses to the enviromnent which we are born with and display as babies. According to the Wikipedia page on these:
"Primitive reflexes are reflex actions originating in the central nervous system that are exhibited by normal infants, but not neurologically intact adults, in response to particular stimuli. These reflexes are suppressed by the development of the frontal lobes as a child transitions normally into child development. These primitive reflexes are also called infantile, infant or newborn reflexes."
Note in particular, the very direct linkage made between "suppressed by the (pre)-frontal lobes" and “as children develop normally".
I believe it is worth anyone with muscle tensions problems or a movement disorder looking into and pondering all the different types of Primitive Reflexes, and also seek to view them in action in videos of newborn babies. There are many such reflexes, but these may include the automatic closing of fingers if the palm is touched, the curling of the toes when the sole of the foot is touched, the turning of the neck, etc. Once we educate ourselves about Primitive Reflexes, we see that Dr Farias is spot on, and we can realize that many physical "symptoms" are actually just the permanent re-activation of one or more maladapted, re-emergent reflexes. Indeed, specific re-emergent Primitive Reflex are actually used as a key diagnostic points in chronic conditions, including Parkinson's Disease in particular. Hence the link between these are various neurological and nervous system disorders are well established.
According to Dr Farias’ work, dystonias are due to a cortical shock, especially in one of the pre-frontal cortices (the right one, more frequently), and this shock prevents the cortex from doing its job of inhibiting the Primitive Reflexes which we displayed as babies. The real underlying problem is then that specific muscles, which would prevent the Primitive Reflexes from activating, are forgotten when the pre-frontal cortex goes into shock. Thus the neural links between the brain firing and sensing these muscles gets switched off. These muscles are not the tense ones, but become weak and flaccid - they are "hypotonic". Other muscles then became overactivated, tense and rigid and painful, in an attempt to overcompensate for the forgotten ones, these muscles become "hypertonic". While most therapies will target the hypertonic, painful muscles, Dr Farias says "look after the hypotonic ones, and the hypertonic ones will look after themselves", and seeks to re-active these forgotten muscles and their neural connections to the brain as part of his unique technique.
Dr Farias has also identified all the muscles which can become hypertonic with dystonias, and all the corresponding hypotonic ones. Interestingly, the picture of sore spots associated with Fibromyalgia shows a strong correspondence with the muscle regions identified by Dr Farias.
Dr Farias's key idea is that dystonia is therefore caused by a "cortical shock", especially to the pre-frontal cortex, and more often in the right hand one, since these are precisely the areas of the brain which suppress, or more properly, inhibit, the Primitive Reflexes as our brains develop. The reasons for cortical shock may include developmental trauma (where, due to environmental failures, one or both pre-frontal cortex do not develop fully), shock trauma (accidents - the right may be more prone to injury due to the asymmetric nature of the hemispheres), shaking or blows to the head (I discovered that I was repeatedly shaken as a baby by a family member in frustration, when trying to get my "wind up"), stress or exhaustion.
So with the pre-frontal cortex now in shock, it can no longer attend to its job of inhibiting the Primitive Reflexes, thus they re-emerge in a mal-adapted way, causing severe and painful muscle tensions, with many ramifications to breathing, oxygen to the brain, movement issues etc.
The Link Between Behaviours and Physical Symptoms
As covered above, the two (unequal in size and function) halves of our brains provide us very different perspectives and awarenesses of the world. Moreover, the different takes on reality which the two pre-frontal lobes provide us, very strongly affect our personalities and behaviours. When these are out of balance, therefore, e.g. if one of these lobes is off-line or damaged, our perspectives, attitudes and actions can be very skewed.
However, what is most telling is that, like myself and many others, Dr Farias has noticed a generalized personality and behaviour profile of people with dystonias, chronic illnesses and traumas. See
for my own observations in this regard.
This actually strongly supports the cortical shock idea, as the resulting re-emergent, skewed personality traits are exactly what Iain McGilchrist’s work on the “Divided Brain” says would happen, particularly if our right hemisphere perspective and awareness of the world, people and ourselves, was switched off, and the left pre-frontal was left, unbalanced, to run rampant.
Indeed, Dr Farias’ observes a profile of common personality traits of many hundreds of people with dystonia that he has interacted in. His description (excerpts below) tallies very closely with what Iain McGilchrist teaches us would happen if the right pre-frontal lobe is offline. Thus the very direct and real link between physical symptoms, through Primitive Reflex re-emergence, and personality profiles is now readily directly related through our new knowledge of the Divided Brain.
"Could it be that we have been trying to analyze dystonia from the wrong angle? Perhaps it can’t be cured because it is not an illness, in the same way that autism cannot be cured because it is a condition, a way of being; a different way of being, of perceiving, living and feeling. Do dystonia patients have personality characteristics in common? In the 900 patients evaluated, many similarities in their personalities can be observed."
"I do not agree with defining my patients as dystonics. What defines them is their personalities, which themselves are very special. People who develop dystonias are hypersensitive, brilliant, impulsive, and have great determination. Among the people affected by dystonias we find United Nations politicians, surgeons, athletes, Olympians, company presidents, dancers; famous musicians, artists, and writers."
"Dystonics also tend to be daydreamers. They don’t pay attention to what doesn’t interest them. When they become interested in or passionate about something, they can engage in levels of extreme concentration which they retain during long periods of time, which sometimes allows them to reach great heights of creative genius"
"There are no limits to the levels of involvement they put into a project... attention to detail..."
"can cause them to suffer from depression or fear of leaving their home."
"....prefer intimate settings with just a few people and suffer from social anxiety when they are in large groups of people."
" Their hypersensitivity is not just emotional, but also sensorial; bright lights, noises, and unexpected movements can all make them dizzy, anxious, or even panicky."
"The same quality that allows dystonics to concentrate so deeply is linked to a tendency to ignore anything that doesn’t interest them and can become obsessive or compulsive behaviors."
"Dystonics have lived in a permanent state of anxiety since they were children, which is why those who seek respite in drugs and alcohol are susceptible to becoming addicts, because their anxiety is part of their personality."
"The motivation that drives them to fight against everything and everyone to defend their beliefs can make them cognitively rigid, not allowing them to abandon a project or a marriage, when clearly it has no future."
"Their impulsivity when feeling attacked or misunderstood can make them become aggressive."
" Their extreme attention to detail makes it hard for them to pay attention to the larger context, to the total vision, or globality."
"Their hyperactivity can make them be careless because they want to read or write more rapidly than they really can. They might skip words or deform their writing to the point of illegibility. "
"They look for shortcuts, solving problems as fast as they can, making use of their talents and becoming frustrated when they have to wait because they are not able to find a solution."
"They can become trapped in a dynamic of instant gratification, a condition they become accustomed to in their youth due to their cognitive and physical abilities."
"Sensory stimulus or emotional experiences that would be difficult for other people to assimilate are enormously difficult for them, take them into states of shock where they cannot react."
"Their tendency for cognitive rigidity can make those states become perpetual, providing them no assistance in overcoming their fears."
Indeed, recently I shared details about my own world view during my life even decades before diagnosis, which I actually called my "un-life", that I’ve now worked out are caused by developmental and shock trauma, and how these aspects were in complete agreement well-meaning but maladapted coping or survival styles well known to many developmental trauma therapists, see
However, we can also now view the coping styles covered there in the context of the Divided Brain too. Indeed, my behaviours and personality in those days can seen as very rampant left prefrontal lobe type traits. I therefore, strongly believe, that I, for one had a silenced right lobe most of my life. I also believe that all I've been doing in terms of therapies actually correspond to nurturing and encouraging my right lobe to come back online, and to improved communication between the lobes, as we will cover in Part 2.
However, I have been thinking on this some more and would like to expand on some points:
I always felt a severe detachment from the world - even if I was standing in the most awe-inspiring landscape, it would not feel like I was in it, as if I was just looking at a painting. I didn't feel present. I still suffer from this detachment issue somewhat even now.
People would point out vivid colors to me, say flowers, and this would seem to cause them joy/awe, but it would do nothing for me, the colours just seemed muted. This has come back to the fore lately, as my friend Jolie Parker is developing and self-experimenting with colored LED light therapy, and she has remarked on several occasions when the experiments have worked and make her fell extremely well and centered that "colors seem much more vivid and brighter"
According to the Divided Brain, these cold detachment from the world, not being present to our lives, are classic rampant left-brain syndromes too.
The Corpus Callosum
Before moving on to how the “Divided Brain” explains many real world, real life observations about Parkinson’s Disease and many other chronic conditions, there are a couple more very interesting facts which tie in with the themes of dystonia (abnormal muscle tensions and chronic pain), movement disorders, and Parkinson's Disease.
Iain McGilchrist’s research also shows us that there is an important part of the brain between the two hemispheres, which separates and allows the communication between them. However, more interestingly and surprisingly:
"the main purpose of a large number of the neuronal connections [between left and right hemispheres via the corpus callosum] is actually to to inhibit - in other words to stop the other hemisphere interfering".
"there are significant populations of nerve cells [in the corpus callosum] that use the neurotransmitter GABA, whose function is inhibitory".
I found this latter point personally very interesting, as I once tried GABA supplementation for a couple of days, based on my interpretation of the excellent article
The supplement switched my movement off completely, and prevented my Parkinson's drugs from working at all for a day or so, each time I tried it, which was quite scary! So the link between GABA inhibiting communication between the two sides of the brain and this inhibition of movement in my case is perhaps indicative of one of the fundamental root cause issues of the condition.
"The corpus callosum permits the left hemisphere to have a greater inhibitory effect on the right hemisphere to a greater extent than the right hemisphere on the left."
"... the right's language inferiority depends to a significant degree on positive inhibition by the left: if the left is sufficiently distracted, or incapacitated, the right turns out to have a much more extensive vocabulary, including long, unusual words."
We began this article with an anecdote about a man who had to have his brain split open to remove a tumour. Interestingly, such split brain operations, where the corpus callosum is cut, were actually once common for epilepsy, and these cases provide much data on all the weird and wonderful things which can happen when the two hemispheres don't communicate, described in Iain McGilchrist's book
While researching the role of the corpus callosum further, I came across some very interesting and pertinent things in the Wikipedia entry on the subject, which connected more of the dots:
"The front portion of the human corpus callosum has been reported to be significantly larger in musicians than nonmusicians, and to be 11% larger in left-handed and ambidextrous people than right-handed people. This difference is evident in the anterior and posterior regions of the corpus callosum. Musical training has shown to increase plasticity of the corpus callosum during a sensitive period of time in development. The implications are an increased coordination of hands, differences in white matter structure, and amplification of plasticity in motor and auditory scaffolding which would serve to aid in future musical training. The study found children who had begun musical training before the age of six (minimum 15 months of training) had an increased volume of their corpus callosum and adults who had begun musical training before the age of 11 also had increased bimanual coordination."
This may be very important, as well as interesting, as musicians in particular are prone to dystonia, especially focal dystonia. Indeed, Dr Joaquin Farias was originally a prodigious musician, who developed focal dystonia at age 21. The question naturally arises: are musicians particularly prone to dystonia because their thicker corpus callosum inhibits the communication between left and right hemispheres even more than usual, thus allowing the left side to run even more rampant due, say, to development trauma issues causing the right to go into shock?
The link between a thicker corpus callosum and left-handed/ambidextrousness mentioned above is also extremely interesting to me, as I once undertook an online survey of people with movement disorders asking if they were left handed/ambidextrous: the results showed that we have far greater propensity to be so than in the general population. Could the associated thicker corpus callosum again make left handers more prone to left hemisphere domination disorders?
While there is probably no way to prove this, it could be the other way round too, i.e. that early and developmental trauma causes left hemisphere dominance disorders, which then, as we continue to develop, leads to a thicker corpus callosum in line with the ingrained perpetual suppression of the right brain during development. This thicker corpus callosum and greater inhibition of the left-right brain communication then leads, for some reason, to the traumatized individual being more likely to be left handed or ambidextrous, and more gifted, natural musicians. The developmental trauma and subsequent life long left hemisphere dominant living then makes us more prone to movement disorders and chronic illness in adulthood, as per the Adverse Childhood Experience studies which have been repeated around the world, thus left-handedness and musicianship and movement disorders become correlated in this way?
In Part 2, we will explore more closely the issues that an imbalanced brain function causes, in particular when the left brain is overly dominant, and show the strong correlation with the major motor and non-motor symptoms of Parkinson’s Disease, as well as common issues in the years to prior to our diagnosis, and we will explore some very interesting direct connections with dopamine and its shortage.