The history of Neurofeedback
There have been many pioneers in the field of neurofeedback dating back to 1875 when Richard Caton discovered electrical activity in animal brains.
- Hans Berger was the first to record EEG on paper and discovered Alpha and Beta waves.
- Edgar Adrian & Brian Mathews reproduced the findings of Berger and in turn brought the field into scientific literature.
- Joe Kamiya with his graduate student Bach showed that voluntary control over EEG was possible.
- Barry Sterman found that cats could be trained with operant conditioning to produce a specific brainwave.
Richard Caton is recognized as the first person to record the electrical activity of the brain.
The recording and training of the electrical activity in the brain has well over 100 years of history. To see where it all began we have to travel back to the year 1875 when a 33 year old scientist by the name of Richard Caton reported to the British Medical Association that he had discovered electrical activity in the brains of animals (mainly rabbits). Caton was a physiologist from the Royal Infirmary School of Medicine in Liverpool, England. Caton used a Thomson reflecting galvanometer with non-polarisable clay electrodes attached to the surfaces of the exposed brains of the animals to measure the electrical activity . In his research, Caton noticed among other things that the electrical activity was reduced during sleep or anesthesia and abolished through death. He also stated that there was an undoubted relationship between electrical activity in the brain and function.
The next few years seen the research into electrical activity in the brain of animals continue. Russian V.Y. Danilevsky's thesis in 1877, although he gave all credit for that to Caton, a report by Ernst Fleischl von Marxow to the Imperial Academy of Sciences in Vienna in 1883 and Poland's Adolph Beck's doctoral thesis in 1890 all added to the building research and alerted more researchers to the trend.
A Physiologist from Russia by the name of Pravdich-Neminski was the first person to illustrate a photographic record of the electrical activity in the brain in 1912, calling it an "electrocerebrogram". His electrocerebrogram was made using dogs with their skulls intact by means of William Einthoven's string galvanometer, which actually won Einthoven the Nobel Prize several years later.
The Birth of Electroencephalography (EEG)
Moving forward to 1924, Hans Berger, a neurologist from Jena, Germany became the first person to record the electrical activity from electrodes placed on the human scalp. Berger wanted to know if he could measure objectively brain function and the mind.
At the beginning of his experimenting with electrical recordings, he was able to successfully record a synchronous frequency in the 10 Hz range, which he called the Alpha rhythm (later called the "Berger Rhythm" by English physiologists Edgar Adrian and Brian Mathews). Berger observed that this Alpha rhythm was most prominent when individuals in a waken state sat with their eyes closed. He found that the Alpha would attenuate if the eyes were opened or if the individual was asked to perform a mental task. Berger also noticed when these Alpha waves were absent, that a desynchronized smaller brainwave was present, this pattern he called "Beta".
Berger published his first research paper in 1929 titled, "Electroenkephalogram des Menschen". The English translation of the Berger's word Electroenkephalogram became Electroencephalogram (EEG), and is the name he gave the device that he recorded the electrical activity on, an invention described as "one of the most surprising, remarkable, and momentous developments in the history of clinical neurology". For a variety of reasons it took till 1935 for Berger's work to be approved. Berger's work had sparked an interest and individuals all round the world were taking on EEG research. Listed below are some of the key names in the history of EEG and neurofeedback;
- Edgar Douglas Adrian "Lord Adrian", an English electrophysiologist looked to emulate Berger's work using the EEG to study the electrical activity of the brain in humans. Along with fellow Englishman Brian Mathews, they were able to confirm Berger's findings. This was a significant step as it propelled the EEG into the scientific literature.
- Herbert H. Jasper -Was the first American to confirm Berger's findings and in 1933 received a grant from the Rockefeller Foundation to set up a Clinical and Experimental EEG lab in America. It was to be at the Bradley Hospital, Providence, Rhode Island. Jasper later went on to establish an EEG lab in Montreal at the request of neurosurgeon Wilder Penfield after successfully aiding Penfield in his surgeries by localizing the seizure activity based on EEG. In 1958 Jasper lead a committee to standardize the 10/20 system of placing electrodes on the scalp which is still used today.
- Joseph Kamiya - In 1958 Kamiya, who taught at the University of Chicago, became the first person to demonstrate that an individual could correctly determine what brainwaves they were producing. The story goes that Kamiya, working with his graduate student Bach, had him predict when he was producing a certain brain wave. Kamiya chose to study the Alpha brain wave (8 – 12 Hz) and placed an electrode in the Bach's left occipital lobe. The experiment had two parts; In the first part with his eyes closed Bach was asked whether he was in an Alpha state. Each trial consisted of 60 tones with 60 guesses in a 30 minute session. On the first day he guessed with about 50% accuracy. The second day he guessed with 65% accuracy and on the third day he guessed with 85% accuracy. Finally on the fourth day he was almost entirely correct. In the second part of the experiment Kamiya asked the student to go into an alpha state when the bell was rung once and to not go into the alpha state when the bell rang twice. Bach was very masterful at being able to get into alpha state at will. Kamiya went on to record that he found that some of his subjects had great control over their brainwaves while others did not have as much control. Most importantly though Kamiya had demonstrated the an individual could have control over their brainwaves.
The Birth of Neurofeedback (EEG Biofeedback)
To see where Neurofeedback began we move forward into 1965. A sleep researcher by the name of Barry Sterman from the University of California, Los Angeles, was working on an operant conditioning experiment with cats connected up to EEG so he could monitor their brain activity. The experiment went something like this;
Sterman placed 30 cats wired up to EEG in cages and deprived them of food as to make them hungry. One by one the the cats were moved out of their cages and in a chamber. Inside the chamber there was a lever and each time the cat pressed the lever they were instantly rewarded as their bowl would fill with a mixture of milk and chicken broth (a cats favorite food seemingly). The cats became conditioned to this very quickly and whenever they wanted food (which is all the time), they pressed the lever and hey presto! the bowl is filled back up. Sterman decided to shake things up and introduced an extra element to the experiment, a tone. Whenever the tone was playing the bowl would not fill up, regardless whether or not the cat pressed the lever. The cats soon worked it out though and sat patiently waiting for the tone to stop before pressing the lever and getting their reward.
Now here is where the interesting part came in. It was during this waiting state that Sterman noticed something unusual in the cats EEG, he noticed that while the cats were sitting there in their absolutely still but extremely alert state waiting for the tone to stop, they entered a unique state of consciousness. This state of consciousness had an EEG “spindle” that was very rhythmic in the 12 – 16 Hz range and it was overlying the sensorimotor cortex. Sterman called this activity SMR for sensorimotor rhythm.
In the third part of the experiment Sterman wanted to see if a cat could be conditioned to produce this SMR brain wave activity on demand. This time Sterman rewarded the cats for producing a half second of SMR freqency, and low and behold over time the cats learned to produce this frequency at will. But what good was this? In a nice twist of fate, what happened next put a whole new dimension on the importance of the cats being able to change their brain waves.
The National Aeronautics and Space Administration (NASA) contacted Sterman to ask if he could research a problem with their astronauts. The astronauts were experiencing symptoms such as headaches, nausea, hyperventilation, hallucinations, and seizures when they were exposed to monomethylhydrazine (MMH), a type of rocket fuel. Sterman used a selection of cats from from his lab to evaluate their brain activity when exposed to the fuel. He would inject them with MMH and then monitor the EEG. Within an hour of injection most of the cats went into grand mal epileptic seizures. Amazingly, the cats that were trained to producethe SMR in the previous study either showed a significant delay in the occurrence of seizures or, in several instances, showed no seizures at all.
Naturally Sterman was intrigued by the seizure resistance of his cats and began to experiment with humans suffering from epilepsy . In 1971 Sterman indeed confirmed that increasing SMR activity over the motor strip can reduce the frequency, duration, and severity of seizures in humans with epilepsy. Sterman had set the way for the field of neurofeedback!
For a really thorough history of neurofeedback read Thomas F. Collura's article on the History and Evolution of Electroencephalographic Instruments and Techniques.
