Medical Background (400BC - to date)

400 BC Hippocrates, who examined the brain during autopsies he performed, concluded: “The brain of man is double”. He also made the connection that loss of speech was connected with damage to the left side of the brain.

In 1864 a French surgeon named Paul Broca came to the same conclusion after observing that patients with aphasia (loss of speech) had damage to the left-brain.

In the 1960’s Philip Vogel and Joseph Bogen performed their breakthrough split-brain surgery (which involved severing the ‘corpus callosum’ that connects the two halves of the brain) on three epileptic patients. Roger Sperry (who received a Nobel Prize for this work in 1981) with his colleagues Bogen, Vogel and Gazziniga tested these patients and discovered that the two hemispheres control vastly different aspects of thought and action. They found the left (controlling the right side of the body) is dominant for language and speech and for analytical and logical thought, while the right (controlling the left side of the body) excels at visualising, holistic and unstructured tasks.

This breakthrough was followed by brain dominance research by Ned Herrmann, Jaquelyn Wonder, Priscilla Donovan, Beverly Moore, Kobus Neethling and others.

1980 – to date Kobus Neethling performed extensive international research on left/right brain functions under the research guidance of Prof. Paul Torrance of the University of Georgia. He first developed the Brain Profile (also known as the Neethling Brain Instrument, NBI®) for adults. He then applied similar methodologies to develop a number of other whole brain instruments. More than 200,000 adults and children from a number of countries have been profiled and ongoing research at a number of universities and institutes remains an essential part of whole brain science. For more information about Kobus Neethling visit