Left Brain, Right Brain

Nearly every book and article you read which is associated with the brain and how it works shows a clear delineation between the left and right brain function. The left hemisphere and the right hemisphere are frequently shown to carry out different functions.

This research which supports this opinion was undertaken in the late sixties and seventies. Technology and experimentation has come a long way in thirty years and this model of brain lateralisation has been proved false.

The lateralisation concept with which we are so familiar i.e. Left = Logic, Analysis, Speech, Right = Intuition, Creativity, Visual Recognition may be appealing but results from; EEG’s, Isotopic Brain-Scans, Magnetoencephalography, Positron Emission Tomography (PET) and EMR’s clearly show that different parts of both sides of the brain are active when any of these or any other ability is practised. Findings indicate that neither hemisphere specialises to the exclusion of the other. Hemisphere specialisation of the type written about in Creativity, Accelerated Learning and Mind Map books appears to be a myth, a ‘given’ which goes unquestioned and simply gets repeated ad nauseam.

In finding out more about the Left/Right enigma it became apparent that just a few initial research findings have been taken and projected beyond what the original researchers intended. Let me give you an example; Dr Jerre Levy PhD is one of the foremost authorities on the functions of the left and right cerebral hemispheres. You’ll find her work represented in the following way : ‘New evidence found by Jerre Levy in her doctoral studies showed that the mode of processing used by the right brain is rapid, complex, whole-pattern, spatial, and perceptual - processing that is not only different from but comparable in complexity to the left brain's verbal, analytic mode. It was also found that the two modes of processing interfere with each other, preventing maximal performance.’

What she has actually written however is: " The two-brain myth was founded on an erroneous premise: that since each hemisphere was specialized, each must function as an independent brain. But in fact, just the opposite is true. To the extent that regions are differentiated in the brain, they must integrate their activities. Indeed, it is precisely that integration that gives rise to behaviour and mental processes greater than and different from each region's contribution. Thus, since the central premise of the mythmakers is wrong, so are all the inferences derived from it". She couldn’t be clearer could she?

Terry

To develop this further you could also add in conceptual (strategic) and operational thinking.

One methodology for this is to use the Herrmann Brain Dominance Inventory. www.hbdi-uk.com

We use this routinely in our leadership and coaching interventions to increase fleibility.

Another source is similar - Gregorc model of Brain Dominance - there is a questionaire in Chapter 6 of "Quantum Learning for Business" Piatkus 1998 isbn 074991792x

original sourse Gregorc, Anthony. An Adults guide to style. Maynard MA: Gabriel System 1982.

email me if you want more

Steve Gorton

Current research indicates that the hemispheres do operate differently, but functions are not as discrete as previously thought or described elsewhere. People can display preferences for being analytical or creative, or learning in chunks or wholes, no question, but to attribute this to brain dominance or hemisperisation would appear specious.

Continuing on from this various writers have seized upon the left/right postulation and created an entire schema around it .

However the quite specific allocation of higher order functions to particular hemispheres seems in sharp contrast to other research most succinctly illustrated on a page of the BBC web site : which shows Language, Maths, Memory and Emotion shared between both hemispheres. How one particular function can therefore be allocated to one hemisphere when the evidence points to a shared system is unclear, especially when one reads the work of Neurologist John Mazziotta at the UCLA school of medicine who states: "Even on the most trivial tasks our studies showed that everything in the brain was in flux -- both sides, the front and back, the top and bottom. It was tremendously complicated. To think that you could reduce this to a simple left-right dichotomy would be misleading and oversimplified"

There are various web sites which provide further reading and evidence about the fallacies which exist concerning Brain Dominance and Hemisphere function, good reading what ever you believe:

http://www.rense.com/general2/rb.htm
http://www.pdkintl.org/kappan/kbru9905.htm
http://users.ntplx.net/~pfarris/essays/psychology/rightleft.txt
http://linus.highpoint.edu/~bblatchl/essay/RightBrainLeft.html
http://www.psychoheresy-aware.org/images/Pro2_14. http://members.ozemail.com.au/~caveman/Creative/Brain/herrmann.htm

Terry,

As a educational and training consultant, I would like to advise you not to rush to the left/right brain theory. It has never been a real concrete finding in neuro science, on the contrary, the infromation processing system of the brain is much more complicate than what the left/right brain theory suggest. I suggest you to visit the ASCD wed site and browse some materials on learning with the brain science.

Angus

Director of Education support and training
Hong Kong

Perhaps the important question here is not whether the theory is scientifically correct but rather whether it is useful in the context of your work.

Conventional management places undue weight upon logical, fact-based analysis and rational, organised approaches to issues (colloquially, 'left-brain' activities). Managers, though, need to pay equal attention to the a-rational, holistic and intuitive aspects of organisational dynamics, and to the interpersonal, feelings-based aspects of leadership (colloquially, 'right-brain' activities).

Anything that raises managers' awareness of these other, critical dimensions of their leadeship role is worth doing. Herrmann's four-quadrant model (set out in his "Whole Brain Business Book") moves beyond the simple left-right hemisphere split to recognise the different roles played by the cerebral and limbic systems. The use of this model can provide a useful way of stimulating value-adding conversations about aspects of leadership and preferred thinking styles. Whether the science is correct or not is of secondary importance in this context. The L-R hemisphere split and/or Herrmann's development of it, simply provides a useful metaphor for helping managers to recognise the need for them to adopt a balanced approach to their leadership and decision making.

I would agree with most of what Chris Rodgers and Bob Rice have written; that this concept can be useful if proposed and used purely as a metaphor in relation to ways of thinking, but when it isn’t and in my experience that's most of the time, (just read some of the statements in this list of postings) then it becomes both misleading and potentially destructive, in my opinion. Learning that you are 'right brain' dominant can merely become an excuse for not taking appropriate action when either “left or right brain thinking” is useful. The same abuse occurs when Honey and Mumford’s Learning Styles questionnaire is used and taught inappropriately, you’ve no doubt heard: ‘I’m an activist I can’t possibly learn from a lecture’. Wrong, wrong, wrong, wrong, wrong.

With regards to the Herman brain dominance questionnaire, one of the dangers with this instrument I think is that if people who complete it are not properly made aware that they may well believe that it provides hard factual evidence of brain dominance, it doesn’t. What it does is: “The Herrmann Brain Dominance Instrument (HBDI) provides a valid, reliable measure of human mental preferences when applied in a professional way, interpreted in conformity with the four-quadrant model, and scored with the approved scoring method.” Taken from: http://www.hbdi.com/

In plain layman’s English; if you use a concept of 4 quadrant thinking this questionnaire provides reliable statistical responses. This is not providing one iota of evidence that the 4 quadrant thinking model is any way physically and neurologically real. Indeed, in this document: http://www.hbdi.com/hbdi/validation-creativebrain%20appendix%20A.pdf
On page 27 of a 28 page validity report the following is stated:

“1. There is a small amount of tantalizing evidence that the brain dominance constructs are related to the selective activation of certain functional subsystems in the brain. While no simplistic geographical model is expected to be valid to explain the four pervasive HBDI construct and the Left vs. Right factors, research with LEG recordings, PET scans, and other methods for measuring brain functioning may reveal stable correlations between different brain activation patterns and different HBDI profiles.”

The key pieces are:

‘There is a small amount of tantalising evidence ~’ and I think there is now more evidence to the contrary but this is merely my own personal opinion.

‘no simplistic geographical model is expected to be valid to explain the four pervasive HBDI construct and the Left vs. Right factors’ I read this as meaning there probably isn’t much truth in this thinking model other than as a metaphor, does anyone else read it differently?

‘research with LEG recordings, PET scans, and other methods for measuring brain functioning may reveal stable correlations between different brain activation patterns and different HBDI profiles.’ ‘May’ reveal, but has it yet?