The idea that the left and right hemispheres exhibit different patterns of thought has caught the public attention and have inspired several educational theories, notably "Eight ways of knowing" by David Lazear , and numerous other self-help books. However theses theories have also been heavily criticized, and sometimes cast as pop-psychological myths .
Here we will investigate current understanding of left-right brain functioning; look at some of the psychological and educational models which result; an examine some of the educational implications. We will also examine for of the critiques of the theory and a couple of speculative ideas inspired by techniques in statistics and computer science. We start with a brief look at the brain.
A simplified model of the human brain consists of many parts:
The cortex is divided into two hemispheres, left and right connected by a thick layer of cells called the corpus callosum. Most other parts of the brain are also divided laterally.
Each hemisphere of the cortex can further be divided into four lobes:
The left hand eye is connected to the right hand occipital lobe and vice-versa. The right hand side of the brain also controls the left hand side of the body.
The outer surface of the cerebral cortex, commonly called the grey matter, is made up of the cell bodies many million of neurons, which are the main processing unit of the brain. Below the surface is the white matter, this chiefly consists of dendrites and axons which connect neurons to each other.
A simplified model of the processing of a neuron is that it receives inputs through its dendrites and depending upon the level of inputs it will fire a signal along its axion. Towards the end of the axion its splits and connects to dendrites of other neurons causing them to fire. While each individual neuron performs a simple processing task, the shear number of neurons give the brain is power. More importantly it is the number of connections which distinguish the way a brain function to the typical functioning a computer today, the ratio of connections to processing unit is much larger in the brain than in a computer.
The behaviourist work of Pavlov and Skinner led Donald Hebb to develop a model of synapse in 1949 that could account for how associations could be formed . This model has become the accepted model and is central to questions on how memories form and learning takes place. Consider the situation where two incoming neurons (A,B) synapse onto a third (C) and (before learning) a signal from A will be strong enough to cause C to fire but a signal from B will not. During learning when both A and B fire together biochemical processes will strengthen the response to signals from B. After learning a signal from B will be strong enough to cause C to fire. This general model has been confirmed by decades of research in memory. During learning specific cells change their properties which can be morphological changes including growth of new dendratic spines, increase in synapse numbers and dimensions and changes in electrical properties of a synaps.
We will now examine the theories of how processing in the left and right hand hemisphere differ.
Much of the theory of left-right specialisation has been developed through examining patients who have had physical defects in one part of the brain. One of the earliest of these investigations was Paul Broca's work in 1861 with a patient nicknamed Tan who had a large cyst in the left hand side of his brain. Tan could only say one word: "Tan", hence the nickname. This indicated that some language functions were concentrated in the left hand side of the brain. Further study of eight patients who all had language problems revealed they also had left hemisphere lesions and the study of left-right specialisation was born.
Since Broca's early work there has been much research into the processing of language. Several specific areas of the brain have been identified which play a part in language (for most people these all reside in the left hemisphere).
In most (97%) right-handed people language is controlled by the left hemisphere. Left-handers have a more even distribution of language in both hemispheres. In 19% this is concentrated in the left hemisphere, and in 68% it is concentrated in the right hemisphere, the remainder have language processing in both hemispheres.
Steven Pinker's "The Language Instinct" , give a good overview of how we process language, the specific roles that certain areas of the brain play and also they types of speech defects that damage to these areas can give rise to.
If language is mainly processed on the left of the brain, then what happens on the right hand side, and what functions do the corresponding areas on the right hand side have? Here research has fewer results which are more contentious.
We shall now move onto the split brain research of Dr. Roger W Sperry.
Nobel prize winner R Sperry's research concentrated on what happens when parts of the corpus callosum, which connects left and right hemisphere, is cut. Some of this work was on animals and some was on human patients who had their corpus callosum cut for medicinal reasons (often to alleviate epilepsy). A typical result of this research involved presenting an image to the left eye (connected to right hand side of the brain), the patient would be unable to say the name of the object (using language centres in the left hemisphere), but could pick out a similar object with the left hand (right hemisphere) . Perhaps the most intriguing split brain research was with a patient of another pair of split brain researcher, Michael Gazzaniga and Joseph LeDoux, who had some limited language facilities in his right brain. This patient show marked preferences in responses from the two hemispheres. When asked, "What do you want to do?" the left hemisphere replied "draftsman", but the right hemisphere (using scrabble letters) replied "automobile race" .
The overall results of Sperry's research can be summarised by his quote: "Everything we have seen indicates that the surgery has left these people with two separate minds. That is, two separate spheres of consciousness" .
Some specific differences between the two hemispheres resulted from this and subsequent research. The right-brain is better at:
|Right Hemisphere||Left Hemisphere|
|Emotions||Negative emotions (fearful mournful feelings),||Positive emotions|
|neurotransmitters||Higher levels of norepinephrine||Higher levels of dopamine|
|Grey Matter White Matter ratio||More white-matter (longer axons) on right||more grey-matter (cell bodies) on the left.|
One particular difference in patient with damage to one side of the brain is how they copy a diagram. A patient with left brain damage will tend to copy the overall outline of a diagram but not the details and a patient with right brain damage will tend to get the details correct but not the overall outline.(Carter)
Often the differences are small, but statistically significant. Some of the results also vary for left handed people. Numerous researchers using have confirmed these results using a variety of techniques. Functional brain imaging using EEG and PET scans, which record brain activity while a patient is performing a particular task are some of the more modern techniques.
One curious fact is that women tend to have a more active corpus callosum with 10% more neuron fibers . The level of connection will have a large impact on mental processes.
Due to the controversial nature of the subject a note on the reference is called for. The above results have been taken from R Carter, Mapping the Mind , pp48-61 and D Falk, Braindance, pp102-107 . Both books are popular science works rather than academic articles. However both authors seem to present relatively unbiased results of the scientific literature. Carter is a medical writer and she used the assistance of C Firth a Welcome Principal Research fellow as a consultant. Dean Falk is a professor at SUNY specializing in neuro-anatomy and biological anthropology.
I have not found any reliable sources which contradict the above findings. The critiques tend to focus on the interpretations of these result, of which more will follow below.
Of the above results the difference in the ratios of grey matter to white matter in the two hemisphere seemed deserves some more investigation. From a computational point of view the difference in these ratios can partially explain some of the differences in functioning of the two hemispheres.
In the field of computer science different types of processing tasks require different types architecture. The typical desktop computer will have a single central processing unit, which will read and write data to from its memory. The central processing unit acts in a sequential manner performing a large number simple operations one by one at a very fast pace (several orders of magnitude quicker than the human brain). This is an example of an architecture with few connections and a very fast processing unit. This type of computer excels at performing routine processing tasks such as simple mathematical processing. The task of displaying a word processing document can easily be broken down into a sequence of mathematical operations that convert the data in memory into pixels on the screen. However it is poor at other tasks, often those which humans are good at: recognition of speech and images (faces).
The field of Artificial Intelligence has struggled for many years to make any progress in these fields. Speech recognition is finally becoming more reliable, and visual recognition is only beginning to make progress. For these tasks a very different types of architecture show better results. These are often based on Neural Networks which have been heavily influenced the structure of the human brain and the Hebb model of learning in the synapse. The distinguishing feature of this approach is to have a large number of simpler processors and a very large number of connections between them. Using feedback techniques this type of architecture can be made to learn by strengthening some of the connections between processors and weakening others.
Speech and visual processing are mathematically two very different problems. Speech is a one-dimensional temporal problem where as vision is a three dimensional special problem. Speed of processing is more important for temporal problems, whereas there are more interacting variables in spatial problems and requiring tasks like mentally rotating objects. The types of architecture for the two will be different. Speculatively the types of architecture for the two could depend of the ration of processors to connections with more connections required for the latter, i.e. the type of distinction observed in the different hemisphere. An emerging field is beginning to look at spatial-temporal problems which may require different architecture again.
Even more speculative is an evolutionary approach to human brain development. The bi-lateral nature of the cortex perhaps owes most to our evolutionarily heritage where the brain has developed from the earlier mammalian brain where there was a direct connection with the left and right hand sides of the body. Now if we have a bi-lateral cortex, there are two main options, either it can be a pair of redundant systems each performing the same task (as in control systems of an airline), or the two halves can specialize. The cost of redundant systems is probably outweighs the advantages indicating a need to specialize. But how to specialise? One very simple way to achieve this would be to subtly alter the grey matter/white matter ratios and also the presentation of neurotransmitters. The results we see in the human brain could be a simple consequence of this specialization with the variations in functions tending to happen in the side most suitable for it. I have no evidence to backup this paragraph apart from a bit of (right brain) lateral thinking.
Ned Herrmann is "Father of brain dominance technology". He drew on the work of Sperry and developed the theory brain dominance where people develop a dominant mode of thinking preference. These can range from an analytical "left brain" approach to "right brain" approaches involving pattern matching and intuitive understanding. These preferences have their roots in our genetic makeup and how it affects our underlying cognitive capabilities. For example left-right handed preferences have been observed in the womb. As we develop we tend to respond with our strongest abilities as these lead to quicker short-term rewards. This can create a positive feedback system that will strengthen those abilities. Eventually this can lead to a powerful preference for one style over the other and a dislike and discomfort for other modes of thinking.
Herrmann then went onto develop the four-quadrant model of cognitive preferences and a questionnaire called the Herrmann Brain Dominance Instrument (HBDI) , . The inspiration for this model came from dividing the brain into as four different systems with four preferred styles:
An immediate critique is that there seems to be little evidence for differences in the left and right hand limbic systems. However, Herrmann's system does not try to be an accurate model of the way the brain functions. Instead it should really be thought of as a model of different styles, partially inspired by the brain, but also the result of extensive questionnaires. As he refined his questionnaires four (rather than just two) separate clusters seemed to emerge which are reflected in the model. Considerable work has gone into testing the validity of this system with overall positive results.
It is worth examining these four styles in more detail:
One of the central ideas of the Herrmann's approach it to develop "whole brain thinking". This focussing on strengthening the week points by using techniques that require a particular style of thinking. This can lead to "Creative problem solving" where a combination of different techniques can be used to arrive at a better solution.
Herrmann's theory offers a strong critique of traditional educational practices. These can be viewed as focussing on sequential reasoning skills and digestion of established theories. Creativity and C and D quadrant skills are often overshadowed or actively discouraged .
An equivalent non-proprietary instrument developed was developed by Eugene Raudsepp: online test.
A related but independent theory is Howard Gardner's 1983 theory of Multiple Intelligences . Here he identified seven types of intelligence:
Gardner later added Naturalist Intelligence and Existentialist Intelligence. Whilst Gardner had a background in neuro-psychology he does not appear to make any specific links between brain science and his theories. Gardener is a strong believer in the plurality of intelligences and does not consider these to be the definitive set. He is also keen to differentiate intelligences from learning styles. David Lazear's "Eight Ways of Knowing" expands upon this theme giving many sample exercises for each mode, as well as a rather uncritical review of the literature. The visual-spatial seems to have some aspect of right brain styles.
Of these the logical-mathematical intelligence seems a questionable grouping. Arithmetic is often associated with the left brain sequential processing yet there is good evidence that mathematically gifted children tend to be left handed implying a right-brain dominance . This could reflect a difference between early mathematics which is often a repetitive rote learning, and more advanced mathematics which often requires high levels of visual-spatial reasoning and abstract thinking. The naturalistic grouping is also questionable, some very different skills such as classifying flora and fauna (very much a analytical/sequential skill in Herrmann's system) to immersing yourself in a natural setting (accessing emotional and holistic preferences).
Two other theories are also worthy of note: The 4MAT System of Learning styles developed by Bernice McCarthy is derived from the Kolb learning cycle and identifies four main types Divergers (Why questions), Assimilators (What questions), Converges (How questions) and Accommodators (What if questions). Studies have questioned the validity of Kolb's model.
The VARK (Visual Auditory Reading Kinaesthetic) is another related model. Whilst this shows some characteristics of a left-right distinction, such as the presence of Visual and Kinaesthetic components associated with the right hemisphere, it is more a model of perceptual style rather than cognitive style. It does not address the different modes of thinking exhibited by sequential/holistic styles.
The other is the, currently in vogue, Mayer-Briggs personality type index. Here four axes are used to record a persons dominant personality type: introversion/extraversion, sensing/intuitive, thinking/feeling and judging/perceiving. This gives a total of sixteen different types. Recent research (New Scientist, last year) has shown good correlation with some of these types and the presentation of certain genes. There are many other personality type theories and even C G Jung has got into the personality type debate .
If a simplified form of Mayers-Briggs, without the introversion/extraversion spectrum, is used it can be shown that it is essentially equivalent to the HBDI after some rotation of coordinate . In particular sensing/intuitive spectrum (openness to interpretation in the Big 5 model), fits well with a simplified version of left-right hemisphere specialization. It is worth expanding on this axis in more detail:
Information can be gathered through sensation (S), concentrating on facts and details, or through a more intuitive (N) process that seeks and constructs patterns and uses a global or holistic information gathering style
All the above models seem to echo some aspects of the left-right specialisation. As an aside we will briefly examine some of the underlying mathematical techniques used.
Various correlations can be made between all these different theories and also with left-right preferences in the brain. It could be said that each theory shows a different aspect of the same fundamental variations.
The number four (or eight) also seems to be popular in these theories. Perhaps this has more to do with the way we perceive information rather the underlying science. For example: splitting things into four quadrants allows two axis to be drawn which means that the variations can be easily drawn on the page. Also it is commonly believed that the maximum number of things we can hold in our short term memory is six of seven. Having four types makes it easy for us to remember the systems!
A mathematically more elegant theory would be to consider that there are actually a very much higher number of variation, which maybe do not nicely fit into convenient categories, perhaps related to individual gene expressions. Indeed one researcher Guilford has identified over 120 factors to the structure of the human intellect .
Principal component analysis is a statistical technique used for analysing data with a very large number of (correlated) variables. In this mathematical operations are applied to the data to pick out the dominant modes of variation. It is typically found that a large proportion of the variation can be summarised by the first few modes of variation. It could well be the case that the above theories have stumbled upon some of these dominant modes, and other theories report observations which are combinations of these modes. This opens up the question that there may be more as yet undiscovered modes which have weaker responses.
This type technique has been successfully applied to the multitude of different personality test. Which has shown that most are subtle variants on the Big5 test.
The whole field of left-right specialisation has been received some very vocal criticism.
"Brain scientists will tell you that the idea of a rigid divide is a popular myth. They even have a word for the public's enthusiasm for the subject: 'dichotomania'. Like 'modern phrenology' the word is a put-down, intended to imply that the real situation is far too complex for simple conclusions to be drawn." , emphasis mine.
I've found no substantial criticism of the underlying science, most of the criticism seems to be of some of secondary works which draw conclusions far removed from science. The word rigid in the above quote is particularly important. It would be incorrect to say that anyone is "left brained" or "right brained" or that a particular task is carried out solely in one hemisphere. Its better to talk of general trends, indeed results from Herrmann seem to indicate that most people have more than one dominant mode . There is also a danger of concentrating one particular aspect of brain behaviour and missing other more important phenomena.
There is also a vigorous globalisation/localisation debate. Are mental tasks carried out over the whole brain or in one particular area? Hard and fast answers seem to be elusive. Brain scan techniques do seem to suggest that certain tasks have greater levels of activity in particular areas. But there can be difference in individual people especially depending on handedness.
The idea of repressed intellect seems to be common in some of these secondary works. With the idea that our intellectual capacity has been repressed by school, and society, and that all we need is a few simple techniques to let our creativity flow.
One particular book seems to be a favourite target for critiques: "Drawing on the Right Side of the Brain: How to unlock your hidden artistic talents" by Betty Edwards . A lot of the criticism seems to be inspired by the title without a careful reading of the inside. Whilst it does present a simplified view of the brain it does also have one of the most concrete and convincing examples of technique specifically designed to utilise certain brain functions. This is concerned with copying a picture. Apparently, one of the problems with accurate drawing is caused by our symbolic processing: we tend to use pathways similar to those used for language to process images and copy images. This can result in a cartoon style result. By the simple procedure of turning the picture to be copied upside-down the symbolic processing is suppressed and very much more accurate pictures result.
Gardner's work seems to have also drawn a lot of criticism . Much of this stems around the use of the word "intelligence", where "interest" might be a more appropriate term. Gardner defines "an intelligence" as set of techniques used to solve a problem or produce a work (e.g. a scientific theory or musical composition) . Personally I'm suspicious over any use of the word intelligence, "learning style" (i.e. techniques we use learn) seems a more concrete term to use. Other critiques focus around the lack of evidence for results from the classroom.
I've found Gardner's work (actually Lazear's interpretation) to be rather unsatisfactory. Certain parts of the classification seem to be muddled, there seems to be no treatment of concepts of holistic (large system, D quadrant) understanding. The work as a whole is void of any critical analysis, instead treating the theory as a given.
Herrmann's work does not seem to have attracted as much criticism, indeed when viewed as a representation of the Mayers-Briggs scheme there seems to be overwhelming evidence for the general scheme. Critiques of Mayers-Briggs (and by implication Herrmann) centre on the methodology used rather than the underlying traits: the lack of falsifiability, the possibility that subjects will give responses to enhance certain characteristics they would like to have, and the dangers of pigeonholing.
If we accept the theory of left-right dominance and learning styles then there are profound implications for education:
Most ... educators take the traditional view of students as being a homogenous learning group, with similar interest in [and] aptitudes for the subject. However, greater learning and understanding may be accomplished if the learning group is thought of as being heterogeneous, that is, highly dissimilar in interest and aptitudes.
These variations have implications throughout the process of education:
Awareness of a students learning styles may help in tailoring a course, although there is a danger of pigeonholing. These need no necessarily be through a formal questionnaire, a teacher may become aware of the styles as they work with the student, showing a good differentiation. Initial assessment such as the VARK test may be useful, but reaction to this at St Austell seems to be mixed:
We don't use the VARK results much as they generally give multi-modal results" Anon.
There seems to be a problem with what to do with the results to the once they are collected. How do we use these results to inform our teaching?
Awareness of their own preferred styles can be a useful tool for teachers: do they tend to work with a particular style? Could other techniques be used in their teaching? How much are their own ideas of education influenced by their preferred styles?
For example when asked the question "What is wrong with education?" a left brained thinker would typically reply, "Get back to basis and discipline - get rid of unnecessary frills like sport and art". A right-brained thinker would rather suggest cooperative, hands on educational activities, including integrating social and creative activities into the whole of education.
And perhaps more importantly how do they react to students with a different style?
Some good examples of very different educational styles can be found in the field of introductory IT.
The European Computer Driving License (ECDL) lies strongly in a quadrant B learning and assessment style. The course material consists of a very step-by-step approach: "type this text", "click this button". The assessment follows a similar style: make this heading bold, and a paragraph here. As such it may be appropriate to many learners, who comprise much of the intended client group, but it might not be suitable to others. Furthermore, it does not address all the skill necessary for fully successfully using a computer, issues like how to design a document or application, or how to successfully navigate the very diverse nature of the Internet.
This can be contrasted with the Open College Network's introductory IT course and assessment. The assessment were heavily based around portfolio building with a criteria referenced making scheme. This more open ended system address a broader range of skills and are closer to how a computer will actually be used. This did require greater input from the teacher and cross-referencing work pieces with criteria can be a confusing process.
The biological understanding of how two the two hemisphere of our brain function has now reached general consensus. There is still much work to do, particularly on the differences observed between individuals and understanding all the brain processes involved on cognition. We may never find the localisers dream of every pattern of though can be located into specific areas, things are more likely to show some combination of local and global processing. No doubt much more will be found this century as techniques of functional brain imaging and genetic understanding improve.
There also seems to be a convergence of the different models of learning styles and personality, which all seem to echo some flavour of left-right specialisation.
However, it probably unwise to make too much of a causal link between biology and learning styles as it can lead to polarised ideas that we are either a left-brained or right-brained thinker. In reality we show a mix of different styles influenced as much by past experience as by biology. The theory gives us just one dimension to describe the vast range of difference in peoples thinking.
These theories, which have been around for the past thirty years, do raise many important questions for education. Has the educational system responded? There is some evidence that it has: there is a wider range of activities used in the class room. But there is still much to address: we still have high numbers of students who do not respond well to education, is this a learning styles issue?
For me studying this issue has been an interesting journey. It has focussed my attention on the different modes of thinking and styles used by the different authors. For example Lazear seems to use a very visual style, trying to describe all aspects of learning, but little critical analysis. Other authors are of a more critical persuasion often presenting their work in a more linear fashion. This raises questions about how to judge each work: is it just a reflection of the favoured modes of the authors and should these be judged by other criteria?
It has also caused me to think about the range of skills used in writing this essay:
These seem to address a wide range of techniques across both side of the brain.
At one point I had hopped to look at how Dyslexia fitted with this scheme, however time and space precluded this. Intriguingly the two examples of quadrant D thinkers in Lumsdaine: Einstein and De-Vinci are both also listed as dyslexic and left-handed. One study seems to indicate that there is a relationship but its far from clear and seems to indicate that dyslexics may not be a coherent grouping showing bi-model results in two laterilazation tests.
To end I would like to finish with a cartoon from Scot Mc Cloud's "Understanding Comics" . For me this illustrates much of a "right-brain style": strongly visual, and big conceptual concepts. If only all education was done this way!
Learning Styles and personality types
You can cite this work as:
R. J. Morris (2006) Left Brain, Right Brain, Whole Brain? An examination into the theory of brain lateralization, learning styles and the implications for education. PGCE Thesis, Cornwall College St Austell, http://singsurf.org/brain/rightbrain.html
Mabel Hearn Tue Mar 27 2007
If they say there seems to be no activity in the left side of a 3 week old baby, does this mean that he will not be able to learn to talk? Please tell me this answer. Thank you Mrs. Mabel Hearn. My email address is email@example.com I really need an answer please if you can help me. Thank You Mrs. Mabel Hearn.
Lewo Tue Apr 24 2007
Left Right Hemisphere Brain Processing Left Right Hemisphere Brain Processing Description
Sowmya . Puttaraju Sat May 19 2007
Very precise , providing hyperlinks for termnilogies will make the article more comprehensive.
Adele Buckley Tue Jun 5 2007
BrainSkiils Read about ways to keep your mind active and how to help your children learn & concentrate on this comprehensive website.
Ron L. Shamwell Sun Jul 29 2007
I found the article enlighting and logically connected to my area of interest.
Houghton Mifflin College Thinking Styles and Learning Styles
Fri Aug 17 2007
GOING BY THIS LOGIC I SHOULD HAVE NEVER PASSED HIGH SCHOOL. I AM PhD. EXPLANATIONS?
Wed Oct 10 2007
GOING BY THIS LOGIC I SHOULD BE A PhD, BUT I AM A HIGH SCHOOL DROPOUT. EXPLANATIONS?
Pranav Prakash Mon Dec 17 2007
It is amazing information, i got to know my brain in more details
Mary Lambie Mon Dec 31 2007
Both my son and I have had several independent tests to determine right/left brain dominance. Oddly, each time we are graded both brained...or mid/whole brained. I have a cousin, who has an IQ of 186, who is also in our situation, though I do not want to suggest my son or I are of that intelligence. Just curious. Any explanation?
MaryAnne Cambell Sat Jan 26 2008
This website is very educational. My daughter is doing a science fair project similar to this and this website is helping her a lot. But, i have one concern reguarding this website. There isn't enough information on the human brain. that's a dissapiontment. At first, i was very happy about this website and i thought it was a big help to my daughter. But now.. i am very dissapointed about this website. You people have gotten me very very very very very very very very very very very very very very very very very very V-E-R-Y!!! MAD. this website is a H U G E dissapointment to me.. U-R-G-H
Dr. S.N.Chaturvedi Fri Feb 1 2008
Well researched work,which couldlead to more R&D in this field. We do need to know ourselves and work towards reaching out to people With the helpof these parameters the Universal theory of Interactive process leads to major gains in all facets of life. Good luck
Fri Feb 8 2008
GOING BY THIS LOGIC I SHOULD DROP HIGH SCHOOL AND MY PhD. EXPLANATIONS?
Tue Feb 19 2008
Coming from the perspective of a person who fit's into the "both" category of the right/left/both dominance argument, I can honestly say that to some extent I'm glad this article exists and to the other extent I think it is missing a few major points. I was "diagnosed" with mixed dominance at the age of 7 (yes the Dr. did tell my mother it was a diagnosis) and now quite a few years later I not only have a BA in computer science but a Master's of Divinity as well. My struggle has not been easy but it's been well worth it. I am fortunate that I can handle the "science" focus as well as a "liberal arts" focus but more importantly I find ease in seeing more than one way to complete a task and even seeing the "two sides to every story." While this gift has presented some interesting challenges in my life -- my "mixed dominance" is a blessing that I would not change. To those who find that this article does not "meet their need for understanding" -- I recommend doing a little research including utilizing the resources listed above.
Karen Mackintosh Fri Mar 7 2008
I had a severe head injury, which left me unable to do certain things. My doctor explained how some of my motor skills had been affected but I now understand how it has also affected my intellectual and emotional capabilities. There are still some motor skills that I need to improve and I can start improving on the emotional and intellectual skills which were affected.
Wed Apr 2 2008
Well I have a very long story to tell, but I'll cut it short. I have a high IQ well did have as a child and as far as tests show Im Bi-Lateral With advanced Mathematic & Logic Skills. But a serious problem happened when I had 3 Hypnotherapy sessions to do with my being Lefthanded. The therapist wasnt aware that I was left handed & to treat my so called nuerosis as he was an old Skool type & actually not much cop, but what he did was instruct me to stop using my Left side of the brain & only Use my right. Get a new perspective. The results were damaging. But having discovered the site today & reading other articles I was able to discover my UNIQUENESS & I basically this morning cured myself of language time and physical problems that Ive had for 7 years. So thankyou VERY VERY Much! :D Now all I have to do is remind myself of my Left side & I feel Alright! And WARNING - NEVER try Hypnosis! SERIOUSLY -DONT
D.B. Thu May 15 2008
I was 12 when I had an illness that was not diagnosed as encephalitis. This was back in the 70's. I realized shortly after something happened, however my parents thought I was just joking around. I had forgotten how to make my bed! For over 2 1/2 years after, I was physically a wreck and phys ed teachers called me lazy. In acedemic class, I struggled (private school) and was way in over what I could work at. Today, I see that my difficulties may have been caused by encephalitis - Alegebra problems, depression, difficulties following verbal instructions/or written if complicated, problems dealing with stress. I have been having problems for many years and it is driving me to the breaking point again!
Dov Marcu Mon May 19 2008
According to Jon Niednagel (brain typing),the J/P dimension fits with the left/right hemisphere lateralization.
brain typing MBTI and the brain
J. Scherer Wed Aug 20 2008
Using both Left and right brain and mastering kersey-bates problem solving mode shifts can be done. The key is non-emotional definition of love in the Bible as a basis of rational thoughts which nearly everyone mistakenly sees as full of emotion when it hints that love is a filter for staying out of reasoning pitfalls by deep study of the proverbs or sayings of the Bible to allow people to learn slowly how to turn off offense as an emotion long enough to analyze any situation for it true dangers and pitfalls and low pay offs easily avoidable by shedding all fears out of reasoning as they arise. Obeying only one fear which when obeyed removes even that fear. You also eventually see Gods active presence of supplying all ones needs moment by moment. Have fun studying cause it sure is great to know God is always right there where you are with answers to every need piled around you. Life is dripping with solutions everywhere and I was blind to that for 52 years until I really wanted to completely commit utterly to Learning Gods way to reason where within 10 years approaching the end of the fifty two years, my awareness of Gods help ready by me deepened until I know God IS. Oh ya, There is a Devil and to get to that awareness of God ,there is often a very great opposition to living for God way until you truely commit utterly to God which takes a fairly long time cause we often have many masks of what we really are( a child who likes stealing cookies that hides them behind our back and lies to our daddy who is God---a loved child which for that time until they always confess when they break the rules often is very useless until the child becomes honest cooperating with God to cleanup the problems created by steal so many cookies. A father can't cleanup any mess a child is continuing to make.
Thu Sep 11 2008
what if you have one side of your brain normal size and the outher side the size of a 4 year old and moast of your matters missing ? and one side of your normal and the outher side slanted and two of your matters missing?
Sonrisante Sun Nov 30 2008
some of the comments are hilarios and entertaining when not taken seriously, but your article is a great introduction and survey of a deep topic.
Nathan A. Knick Mon Feb 16 2009
I was just curious if you could send the reference information for this web site to me. Author, date and anything else you think would be helpful in properly siting this site. Thanks Nathan A Knick
C.R. Sat Feb 21 2009
After reading this article I found that it provided me with a clearer understanding as to how the world and other people are trying to understand and provide answers to the complexity of the brain. I find that reading about all the theories, their results, and their criticisms, it appears that many people have different views and the evidence in to knowing detailed facts about the brain are still quite vague. What was made clearer to me were the differences in the left and right hemispheres, the 4 quadrants, and how all these theories help in today’s education. “For me studying this issue has been an interesting journey. It has focused my attention on the different modes of thinking and styles used by the different authors. For example Lazear seems to use a very visual style, trying to describe all aspects of learning, but little critical analysis. Other authors are of a more critical persuasion often presenting their work in a more linear fashion. This raises questions about how to judge each work: is it just a reflection of the favored modes of the authors and should these be judged by other criteria?” I believe this last statement made by the writer illustrates the best overall view of what people should see in these theories and studies. And that is, that all authors of these theories use different methods and non are completely right or wrong, which is important because they still gave rise to further understandings of the brain and its multiple complexities, which have helped in further developing other fields of life, such as education and the difference between men and women or even the difference between the mentally disabled people and the mentally able people.
S.R Sun Feb 22 2009
This article is very informative and seems to have a fine understanding of the basic brain, brain lateralization, learning styles and personality and educational implications. I found that the research of brain lateralization helped me have a better understanding of it, since I had difficulty understanding it before. It was very interesting to know that, “In most (97%) right-handed people language is controlled by the left hemisphere. Left-handers have a more even distribution of language in both hemispheres. In 19% this is concentrated in the left hemisphere, and in 68% it is concentrated in the right hemisphere, the remainder have language processing in both hemispheres” this intrigued me and I was encouraged to read on further. I also had a good understanding of the left and right hemispheres and their functions for each, such as the left hemisphere being the dominant side for language and the right hemisphere leaning more to the emotional side and some function that are shaded by both, eg: Sensations on both side of face, Sound perceived by both ears. The 4 quadrants were laid out in a simple manner which also made is easy to understand, and how all these theories help in the education of today. Even though this article has given a lot of information from different people, and has evidence for most theories it seems that the details about it are still quite unclear, seeing that there is still so much more of the brain to discover, “There is still much work to do, particularly on the differences observed between individuals and understanding all the brain processes involved on cognition”. Overall this article is very helpful and interesting and gives qualitative information about the brain and other information linked to the brain.
Mon Feb 23 2009
M.K The examination into the theory of brain laterilization, learning styles and the implications for education gave me a informative understanding of the human brain.The fact that the ratio of connections to processing unit is much larger in the brain than in a computer particularly intrigued me as this shows just how complex our brains are and how humans have such great capability.Learning that different parts of the brain control different variables such as grammatical processing, naming objects and recognition of visual symbols helped me understand the biological perspective a lot better. It was especially interesting to find out that the left and right are not completely seperated when it comes to what they control, some variables are shared with both sides. for example, 'sensations on both sides of the face,sound perceived by both ears, pain, hunger and position' are all controlled by the left and right hemispheres.Though the article provided has used many examples and theories it is still unclear as much of the brain is still to be discovered and analysed. However, the article has provided a sound over-view of the brain and has helped me understand it a lot better.
LMvV Mon Feb 23 2009
This article was very interesting and very revealing. It gave a lot of information about the functions of the brain. I found it very interesting that our brain is actually not one whole, but 'two'. The results shown by Sperry's research (about what effects there are when the corpus callosum has been cut) gave some support for this. This research gave interesting results which "can be summarised by his quote: "Everything we have seen indicates that the surgery has left these people with two separate minds. That is, two separate spheres of consciousness" . ' I also found it very interesting that our brain is not only split into two hemispheres, but these hemispheres are again divided into four parts (lobes) which have different functions. Further is it fascinating that our personality and our learning styles are created by the ‘development of a dominant mode of thinking preference.’
Rich (webweaver) Mon Feb 23 2009
Three extensive comments in as many day. I'm begining to suspect there might be a student project a foot. If so please let me know.
LMvV Mon Feb 23 2009
This article was very interesting and very revealing. It gave a lot of information about the functions of the brain. I found it very interesting that our brain is actually not one whole, but 'two'. The results shown by Sperry's research (about what effects there are when the corpus callosum has been cut) gave some support for this. This research gave interesting results which "can be summarised by his quote: "Everything we have seen indicates that the surgery has left these people with two separate minds. That is, two separate spheres of consciousness" . ' I also found it very interesting that our brain is not only split into two hemispheres, but these hemispheres are again divided into four parts (lobes) which have different functions. Further is it fascinating that our personality and our learning styles are created by the ‘development of a dominant mode of thinking preference.’ Overal, this article gave me a way better understanding of the functions of the human brain.
R.L. Thu Feb 26 2009
The thing I found most interesting was the quote by Sperry saying, '"Everything we have seen indicates that the surgery has left these people with two separate minds. That is, two separate spheres of consciousness". Sperry stated that the brain does not function as a whole but is separated by two sides, the right and the left, where each side performs different functions. One of things that fascinated me the most was the extremity to which these two sides were different. ‘In most (97%) right-handed people language is controlled by the left hemisphere.’ From the theories explained in this article, I am able to associate reasons for certain skills that I have. I am left handed which means I use my right side of the brain more. This could explain why I am good at ‘copying designs, music, understanding geometric properties’. Although this article provides some evidence of the difference in functioning between the left and right side of the brain, there is still controversy. Although there appears to be an idea of general localization, there is still much more work to be done to end this debate and to see whether certain parts of the brain actually do carry out specific functions.
KGOMOTSO DIKOBE Thu Feb 26 2009
Have found this page very educative and make it easy for one to understand him or herself and maybe to know which career path to follow.
Sonia Henderson Sun Mar 1 2009
Yes you presume correctly, I did set H/W to read and respond to your website as this is the topic we are currently covering in IB psychology.Well done to my students who added their comments and shame on those who didn't! Hope this was o.k with you and thanks for a such a useful website!:)
VB Wed Mar 4 2009
I believe this website is a very good source, and I will be referring back to it frequently. There are a lot of examples, as well as relevant and interesting studies mentioned that can then be used for reference. What really interested me was 'one curious fact is that women tend to have a more active corpus callosum with 10% more neuron fibers. The level of connection will have a large impact on mental process'. I personally agree with this statement, as I usually state that women are smarter than men in various ways, and after reading this website I know that there is support for what I say. There are also things that interested me, things that i didn't know before I actually read the website, as there were a lot of researchers regarding brain intelligence and the idea of multiple intelligence by Howard Gardner. And last, but not least, I have to admit that I am a right-brained person, and the description that was given describes me only partially. I did some research and found that right-brained people tend to be intuitive, fantasy-oriented and non-verbal as well. To conclude, I think that this website opens up an idea for a bigger discussion about different hemispheres and brain in general, as until now humans do not know every single part in the brain, and there are still some things that scientists and researchers cannot explain.
Helene Wed Mar 25 2009
I like your summary of arguments and counterarguments for hemisphere dominance. It's a shame that many readers don't see the criticism and still believe to be guided by one side of the brain. It is VERY important to note that the comment of Sperry ("Everything we have seen indicates that the surgery has left these people with two separate minds. That is, two separate spheres of consciousness") is related to people with a cut corpus callosum, meaning severe brain damage and the cutting of the gigantic bridge between left and right. Healthy people DO have a functioning bridge, thus information travels and is influenced by BOTH sides. Say Manhattan was cut from the rest of New York City; it would just function as a separate city. However, currently it IS NOT cut off and thus functions in a close harmony with the rest of the city, and in a more complete way than it would function on it's own. Even though certain processes, such as language or orientation, are initiated and controlled mainly by one side of the brain, different areas in the same and the opposite hemisphere have substantial influence on these processes in healthy individuals and overall, your left side will be just as active as your right side. Some people might have more developed certain areas of the brain (pianists tend to have a larger motor-area for the hands, London cab drivers have shown to have an increased area where mapping and orienting is thought to be located); however this is not the same as being 'dominant', it just means you're good in something, or rather in these cases, that you have practised a lot. So I repeat; everyone makes as much use of his/her left brain as of the right brain, any and all neurons that are leaved unused would not survive. Furthermore I have a remark by your statement "Left-handers have a more even distribution of language in both hemispheres. In 19% this is concentrated in the left hemisphere, and in 68% it is concentrated in the right hemisphere, the remainder have language processing in both hemispheres”. This is not true. Only a small part of left-handed people have right-sided language; it is however about 5-20% larger than in right-handed subjects (depending on which study. See for instance Pujol et al., 1999 in Neurology(52) or check the link to search for interesting articles on left handedness and right-sided dominance). You probably were confused with the highly significant correlation of left-handedness with right-hemispheric location of language. In this case it means that not most left-handers are right-hemispheric dominant for language but rather that many right-hemispheric language dominant people are left-handed, which might be in the range of 75%.
PubMed Important site to search scientific papers
Vic Charlton Thu Mar 26 2009
Literacy and Learning How to Read
Dudley Lynch Wed Jun 17 2009
More than thirty years ago, I discovered the data and literature on not one but two "awesomely archetypal" split brain surgeries and constructed what may well still be the world's only quadrant assessment model and tool based solely on brain surgery results. We called it The BrainMap®, and it was the foundation of what has become a whole stable of personal and team assessments, all of which are isomorphic, so to speak, to the total brain model we began with. That is to say, one of the most powerful advantages of using The BrainMap is that nearly all of our other tools are an adaptation of The BrainMap model. Once you've given a person or group The BrainMap, you can simply keep expanding their knowledge of themselves and others by giving them MindMaker6® (values and worldviews), The mCircle Instrument® (dilemma or conflict resolution style), PathPrimer® (purpose orientation) and, the Big Kahuna, Asset Report®: The Book of You (executive leadership orientation and general growth possibilities), and it all fits together. I don't know of anything else in the assessment field that is quite as comprehensive and ever-expanding and -illuminating as all this, and I'm pretty certain that there is nothing in the brain-based assessment field like this. Also, I've written (sometimes with colleagues) six books that illuminate how all this information and personal insight can be put to good use, including a sourcebook on The BrainMap called The BrainMap Workbook. Anyone who is interested in this approach is welcome to visit our website at any time. www.brainmeup.com
Albert Haven, Ed.D. Mon Oct 26 2009
Thanks for a very useful complilation of the theories and science of brain research. I agree with your assessement that regardless of the "proof" of any of the theories, it is clear that left/right and other dominace factors exist. In '69 (or so) I was an elementary principal and learned at a weekend conference of the existence of L/R brain dominance. On Monday, my teachers and I began to screen students for such dominance, and were able to observe that some students fit the pattern. We adapted the curriculum accordingly, and many of the identified students made drastic improvement. The Institute for Instructional Management is continuing the work of helping schools develop multi-modal instructional techniques, along with flexible grouping strategies allowing different dominance based learning activities. The bottom line is that teachers are starting to look for such diferences, and trying to adapt instruction accordingly. As they gain experience, their skill in Formative Assessemen grows, and leads to quite sophisticated analysis and lesson design. Your article is really going to be valuable for such teachers, giving them a framework based on understanding current research. Our website is under development, hopefully up soon. www.instructionalmanagement.org
MVP Mon Nov 30 2009
I believe your all missing out on some key factors, that will help all who want it. The majority of coments are only in reference to mostly Mental asertivness. How about the Physical side, while being in this out of balance state lets take the majority of our population (Left brain) 99.99% of all left brain dominate people are weak on there right side, simple muscle testing will prove this. So with this inbalance, how would the Right side of our body measure up. If we were to measure the leg length of both side, would we not be shorter on our right side. Now If non-releaved stress is the enviormental problem, and that most people are stuck in Flight or Flight stress responce that inhibits the bodys own ability to heal within. This ongoing, and unrelieved stress is what disease, and most disorders stem from. To rub more salt in this open wound, we give doctors the license to prescribe symptom realief while the core issue is slowly degenerating our lifes energy. I have been involved for 2 years with a process called ALPHABIOTICS. This simple technique balances the body with a patteren interupt (like rebooting a computer) instantly stronger on both sides and my stress has minimized greatly. Since doing this, my personal health has greatly inproved and many changes have occured to my overall benifit. Please look into this site for more information, I would love to hear your side if reguardless. Thank you for reading this
Robert Roberson Mon Dec 7 2009
I am interested in and commencing research in what if any impact Left/Right brain people have on decision making and the speed of decision making when confronted with an ongoing and fast moving Emergency/Disaster. I'm particularly interested in the ability of Left and/or Right Brain thinkers to deal with decision making in major incidents in the areas of Incident Controllers, Operations, Planning and Logistics)and want to review some major disasters, particularly Bush Fires,the time lines of positive actions, focusing on time delays and indecision, (procrastination) as against Left/Right Brain thinkers in key positions.
Phil Lehman Thu Jan 28 2010
What is happening when I am both a lefty and a righty but only for a specific task. I eat with my left, write as a lefty, play tennis lefty; but golf righty, bowl righty, shoot archery righty, shoot a shotgun lefty...but shoot a pistol either hand but get confused as to which eye to close. Can someone explain?
shamilathevi Mon Mar 1 2010
Just loved it. Was clear, concise and informative.
Learning Styles Helps identify learning strategy best suited for the two groups.
Don Ayers Wed Mar 24 2010
Hi Do you mean Myers-Briggs in your essay? And, you suggest that David Kolb's work is not valid: what studies show that, please? Thanks
Bonnie Lund Thu May 13 2010
I'm a writing trainer and for years have introduced the simple right/left brain differences as they relate to writing. Is there any recent research on how writing practices differ from left-dominant and right-dominant writers?
JS Tue May 25 2010
The personality types are by "Myers Briggs" not Mayer Briggs thanks
Betty Edwards Mon Jun 7 2010
The author states that much of the criticism of my book centers on the title, which he presents as Drawing on the Right Side of the Brain: How to unlock your hidden artistic talents. The author got the subtitle wrong. It is: Drawing on the Right Side of the Brain: A course in enhancing creativity and artistic confidence. The difference between the incorrect and the correct subtitle, is, at least to me, significant. The author is correct, however, when he points out that from an empirical standpoint, methods described in my book do work, as Roger Sperry himself pointed out in a statement on the back cover of the original book. Betty Edwards
Dr. Bill Morgan Mon Jul 19 2010
In my profession I teach piano lessons and typing. I have begun to wonder whether there are any developmental effects on the whole brain that can be measured?
Doc Frog's Blog Discussion of best practices on computer keyboarding instruction.
Temptom Tue Jul 20 2010
It's funny about the last comment asking about typing, because I was thinking about that as well. Since both hands are in a co-operative effort of outputting a mixture of mental efforts. I suppose that kind of dovetails with overall gist of the article; much is known about the brain's division and co-operation of labor, but much is still not known. It was a very interesting and informative read, but perhaps in need of a second go through, there were several errors that seemed due to a lack of proof reading. Most spellcheckers will tell you if you incorrectly spelled something but not if you used a similar sounding word spelled correctly, IE, week instead of weak or basis instead of basics. It's nothing major, context usually makes the author's intent pretty clear. I'm just nitpicking. Thanks.
carol J. Miller Wed Jul 21 2010
I don't know if there are any developmental effects on the whole brain that can be measured, but I'd like to learn more about that. I have a personal experience that could add to the understanding. When I was a child I took piano lessons. Now, I come from a very creative , artistic family. My brother is left handed and dyslexic and an artist. My son is also left handed and an artist and photographer. I had difficulty with my piano lessons, however I was very successful at typing! I seem to have an output challenge. I have a hard time getting the notes onto the piano with the needed timing and rhythm.If I memorized the music and practiced it, I could play it. I could not read it and play it from page directly to keys. But I had no problem typing quickly. I think as long as my brain is not concerned with the rhythm(creative) side(like while typing)things flow. Its as if that creative part is separate from the mechanical part. I am also an artist.I find I have difficulty with written word directions, and spoken word directions, but give me a map with pictures and I'm just fine! As you can see, I have compensated over the years and deal with words quite well. I think this is a neat discovery!
Mon Oct 4 2010
You can tell by your comments that people still don't get it. I'm often told it's "only possible for a few geniuses" to develop both "creative" and "logical" skills. Take web design, for example. Web design is a subset of both art and science. I have found it nearly impossible to convince "artistic" types that a web designer can be an artist. Conversely, I've found it difficult to convince programmers that a web designer can be trusted to think logically and understand technical limitations. Both groups have a vested interest in believing that they, by virtue of being either "right brained" or "left brained," have a leg up on the other group when it comes to their particular specialization. "I just don't get (art/programming). I'm just a (left/right) brained person and my mind just doesn't work that way." It's far too easy to draw these mistaken conclusions from poorly presented lateralization research. Not that yours is. And goodness knows people would cling to their impressions even if you put it at the top in huge red print.
Helen Taylor Fri Feb 4 2011
You're mixed handed, like me. I pick labels off, tear tape off, do buttons up and unwrap CD's with my left, but do most tool use and write with my right. I can spanner with both, and sew with my right hand but many of the stitches I do in embroidery , I do backwards. I can touch type to 180 wpm, too! I also have the mixed handers very early memory - I can remember being in my stroller and can remember being lifted into a shopping trolley seat, which puts my early memories at about 2 and a half, with average very right or left handers being around age 5. I prefer to shoot left handed and do archery left handed, too. And when using a long handled brush, I show no preference which side I stand or which hand is highest on the handle. I'm an INTJ on the Myers Briggs, and the perceived personality fits me perfectly. Oddly I know no less than six NTJ's, either I or E, and they all work in science. I have a better than strong interest in science myself, and get on with that personality type FAR better than any other! There are lots of advantages to being in the middle of the handedness spectrum! Search for The Edinburgh Handedness Inventory but be careful. I only qualify on the broom handle, the other things I'm right handed. But I'm clearly left handed in some things, and pretty much like you are. It runs in families too, my father and his mother were both mixed handed. HTH
Janey Edwards Sun Mar 20 2011
I would like to quote from this article. Who is the author, please? I am a "brain profiler" in South Africa, using the NBI (Neethling Brain Instruments) model. My quest is to get educators to acknowledge how students think differently and to empower them to maximize their teaching through devising lessons that embrace all thinking and learning styles. It worked for me in my teaching career. It's amazing how this understanding makes teaching and learning so much more effective.
Dr.Parameshwari Sat Jul 9 2011
BrainTrain asite on whole brain development program
Andy Thu Aug 4 2011
It seems like this is good information, but I have to question whether or not someone who doesn't even proofread his article has taken the time to check his facts. The unbelievable amount of typos is quite distracting from the topic at hand.
Judith Jaffe Fri Aug 12 2011
I found so much of interest in this article but almost couldn't read it due to the poor quality of the editing. i experienced a level of physical discomfort during the effort! what does that say about my brain?
SAMA Thu Sep 8 2011
i give you some info. and i want to know which talent i have more to work on and modify them. in my CT scan hypo dense on left frontal of my brain is seen.i have had the problem work and do things by my right side of my body since childhood, but it wasn't so significant that anybody can not distinguish it in person. please help me to know my talent more.
J Face Thu Oct 6 2011
I was diagnosed with dyslexia in second grade I don't spell very well and math is a great challenge I am great at painting pictures and I type well and fast. I cut hair I can change the clippers to either hand and I can cut hair by looking into a mirror and not the actual person. I can play the piano by ear and. I have above average writing skills according to a test I just took. and as a child in first grade I tested at high school level for logic and reasoning. I switch from hand to hand while painting. I am extremely verbal what am I? I have been trying to figure out my learning dominance but I do not fit the statics for being more right brained I would love to get you input
rick Wed Oct 19 2011
i'm a college student taking Engr. , i love math i understand it but sometimes i forgot a lot of formulas it's like i understand it today then after a week i can't then after a month i remember it again. i can also play keyboard by listening or watching but i can't read the notes. sometimes i can solve hard problems but i can't solve easy problems sometimes i think i can solve hard problems ............. i try the spinning dancer brain test and first try i saw it spinning counter clockwise but when i looked at is again lately i saw it spinning clockwise . can expaline to me what kind of thinker am I?
MMA Brain Study Sat May 9 2015
This point is located at the outside nook of the eye. It is the starting of the Gall Bladder meridian.
Parag Jasani Fri Jul 3 2015
Human brains are FULLY lateralized The truth behind the Left Brain-Right Brain theory http://brainduality.com/LBRBTMR.aspx