Nobel Prize Winning neurologist Roger Sperry's 1960's split brain experiments, confirmed that different functions are lateralised between our two brain hemispheres. In a normal person the two halves communicate via a thick nerve sheath called the corpus callosum which ensures that they work. But we still tend to label people as "left" (logical) or "right" (imaginative) brained.
Dr Paul McLean looked at it from a different perspective with his Triune Brain model proposed in 1952. He suggested that the brain is made up like an onion, each layer superimposing over the other and that this has built up over time as our human needs have expanded. Within each hemisphere it is proposed that three brain layers exist :
Ned Herrman put these two ideas together developing his four quadrant model. He suggests that within each hemisphere we have the limbic and cerebral element. Thus we have a limbic left and right and a cerebral left and right.
- The oldest evolutionary stem or reptilian brain layer (5%) controlling sensory motor functions, survival. Used for fight or flight. When it dominates we get brawn not brain.
- An emotive/cognitive/feelings limbic brain layer (15%) which controls biorhythms, sleep patterns, blood pressure and temperature. Long-term memory. Filters information in and out and governs concepts of value and truth.
Learning must be as multi sensory and emotionally engaging as possible - the dull, boring and repetitive will be filtered out and not engage our thinking brain
- The youngest modern day brain layer (80%) - the Neocortex which represents 80% of brain. Reasoning, language, intuition, language, visual, spatial, kinaesthetic, musical, interpersonal
Divided into left and right hemispheres - the logical left and the intuitive right