The functions of the left and right hemispheres are widely misunderstood, but in brief the functions can be interpreted as follows:

The left hemisphere controls anything to do with space and time (most of what we call ‘thinking’ in the West). It is where we do our calculating, analysing and planning. It deals with pattern recognition.

For instance when you walk into a room you immediately recognise the chair, the table or other objects in the room even of you have never seen that particular chair or table. What is more, you can tell objects from shadows, and where one thing is front or behind another. The left brain deal with details rather than the big picture. If we consider the brain as a computer (and it must be made clear that this metaphor only takes us so far), the left brain has the programs.

When you want to catch a ball you must concentrate on the ball, not on the mechanics of how you move you hand or your arm. You rely on the brain to enact the series of movements that will catch the ball.

Many people would have had an experience similar to this: You are watching television and an advert comes on, and you get up from your chair go to the kitchen and to the refrigerator, open the door and look in and then suddenly ‘come to’ and wonder to yourself why you got up from the chair. What happened was that a ‘program’ in the left hemisphere was initiated that took you into the kitchen and then when it ran through to completion you were left wondering why you initiated the program in the first place. Maybe there was an advert for ice cream that caused you to go to the kitchen. The left hemisphere controls the right side of the body.

Left Brain Processing and Autism

Autistic people have a deficiency in left-brain processing and, in its extreme, they are unable to recognise patterns. Can you imagine walking into a room and all you see is shapes? Dr. Temple Grandin has researched the relationship between autistics and how animals see the world. Animals have very different pattern recognition to humans and may get spooked by a shadow.

The right hemisphere is much less well understood in the West but is better understood in Eastern cultures. It is to do with being in the present. In our computer metaphor, this controls the raw input from the peripherals. For instance, whenever you move your mouse it sends signals to the computer to indicate that it has moved a certain amount horizontally or vertically. The computer interprets these signals as a particular position on the screen. Similarly, each ear send a series of signals to the brain that indicate sounds of a particular amplitude (volume) and frequency (tone). The right hemisphere of the brain deals with these raw signals. It does not really distinguish between signals that come from the eyes, the ears, the nose , etc.

The right hemisphere deals in the big picture, rather than the details. It controls the left side of the body.

Right Brain Processing and Asperger’s Syndrome

People with Asperger’s syndrome typically have a deficiency in right-brain processing. They are very good at the left brain functions: language, calculating analysing and so on, but are very poor at right-brain skills: empathy, reading body language and imagination. They are often very literal in their thinking. A friend of mine who was dating a man with Asperger’s syndrome once, out of frustration, asked him why he couldn’t be more affectionate. “That’s quite easily solved”, her companion replied, “Simply write down a list of what you want me to do and I’ll do it”. Lists are very much a left-brain function.

People with synesthesia have their senses mixed up so that they may hear colours and see smells. People who experience some hallucinogenic drugs such as LSD can have a similar experience.

My stroke of insight

On December 10, 1996, Dr. Jill Bolte Taylor woke up to discover that she was experiencing a stroke. The cause proved to be bleeding from an abnormal congenital connection between an artery and a vein in her brain, an arteriovenous malformation (AVM). The malformation was in the left-hemisphere of her brain. Dr. Taylor was a professor of Neuroanatomy at Harvard University and as such she was able to observe the process as the left-hemisphere functions slowly shut down.

Gradually the right side of her body ceased to function properly. She staggered down the stairs and knew she had to phone someone. By the time she reached her phone index card, she had lost the ability to process patterns and she had to painstakingly compare the shapes of the digits on the card with the shapes of the digits on the telephone keypad. At the same time her consciousness moved from the left hemisphere to the right hemisphere and, to quote her, she became ‘at one with the universe,’ ‘there was no space or time’. These are phrases that she admitted had she heard them before she had her stroke she would have dismissed the quoter as being a hippy wacko!

She wrote of her experiences in her best seller ‘My Stroke of Insight.’

The concepts of a fundamental difference between the functioning of the left and right hemispheres of the brain has been dismissed by many in the scientific community. One professor put it:

It is unfortunate that Jill Bolte’s dragged out the left-brain/right-brain stuff as an explanation for her experiences since the brain does not work that way. In other words, while the sequence of events might have been somewhat different, she would probably have had the same sorts of experiences had the stroke occurred in the right cerebral hemisphere rather than the left.

This ‘sceptical’ mindset is something we will discuss later on but the left and right hemisphere difference is substantiated by the work of another neurologist, Dr. Vilayanur S. Ramachandran.


The doctor was examining a condition called anosognosia, which typically results from damage to the right parietal lobe (the right hemisphere) of the brain. A patient with this syndrome is convinced that although they are paralysed on one half of their body, they are normal. So a patient asked to clap their hands together will wave their right hand in the air or clap it against their chest and will be convinced that it is functioning normally. When asked to tie their shoelaces (a task that is impossible to perform with one hand without considerable practice), they will persist at the task indefinitely.

This syndrome only occurs where the damage is to the right parietal lobe, which led Dr. Ramachandran to develop a theory as to its cause. He theorised that the left hemisphere of the brain is concerned with logic and working out causes and effects. For example, when you see a door you understand what it does and how it opens even if you have never seen that particular door before..You can deduce this from your experience with other, similar, doors. This is the function of the left hemisphere. On the other hand, the right hemisphere acts as what he called the ‘devil’s advocate’ (Milton Erickson used the term ‘Pattern Interrupt’ because it interrupts the patterns executed by the left hemisphere). This is the part of the brain that questions whether that particular pattern is appropriate and questions the relevance of the deductions of the left hemisphere. This allows you to adapt to changed situations.

In the case of the patient with anosognosia, the right hemisphere is damaged so even though the situation has changed (that is, the patient is paralysed in one half of their body) the inactive right hemisphere is unable to question the deductions of the left hemisphere, which has previously worked out that the body is able to function normally.

Dr. Ramachandran tried a strange experiment. He poured water into the left ear of the patient with anosognosia, which, for unknown reasons, stimulates the right hemisphere. For a short period the patient is able to act normally and is aware of their paralysis. When this wears off the patient reverts to the condition, even denying that they could ever have admitted to being paralysed.

This model of the brain corresponds precisely with the model described by Jill Bolte Taylor. The right hemisphere deals with being in the moment, the raw input from the senses as it were, whilst the left hemisphere forms patterns so we can learn from experience.

Developing the right brain

In an article in Newsweek magazine, professor E. Paul Torrance. Schwarzrock describes how since 1990, whilst IQ in children has been going up, the results of another test he gives for creativity has consistently been going down.

One thing that is not well understood in the West is the importance of game playing in young children. This stimulates the right hemisphere of the brain. Many parents push their children into sequential learning from an early age, which stimulates the left hemisphere. Children who have been taught in this way tend to be very intelligent, in the sense that they score well in IQ tests, but lack the ability to think laterally. Such people often become sceptics because having worked out (or had explained to them) a logical explanation of how something works, they are closed off to situations that are exceptions to these rules.

The ‘devil’s advocate’ is not performing properly as it was never developed in childhood.

Of course this is not confined to sceptics. Blind adherents of political parties, flat Earthers or religious ideological extremists also fall into this category. Talking to these people can be as frustrating as talking to a person with anosognosia would be.

The left and right brained approach in children can also be described as following instructions (left hemisphere) and creating new ideas (right hemisphere). In the old days of traditional playing, a boy would play with a box which a fire engine, then it’s a house then he puts it over his head and he’s a robot. When Lego and Meccano first came out they were made of basic building pieces that a child would assemble to form various constructions. Nowadays, you buy a Lego robot or bakery. These are, ironically, described as educational because children learn to follow instructions.

Computer games have contributed enormously to the decline in creative thinking. You are confined to the rules of the game. You can’t, quite literally, ‘think outside of the box.’

By Philip Braham on July 24, 2018

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