From diagnosing brain disorders to cognitive enhancement: 100 years of EEG have modified neuroscience

The electroencephalography (EEG) was invented 100 years ago. In the years since this device for monitoring brain electricity was invented, it has had an incredible impact on the way in which scientists study the human brain.

Since its first use, EEG has shaped researchers' understanding of cognitive processes, from perception to memory. It can also be essential for the diagnosis and treatment of diverse brain disorders, including epilepsy.

I’m a cognitive neuroscientist which uses EEGs to check how people remember events from their past. The one centesimal anniversary of the EEG is a possibility to reflect on the importance of this discovery in neuroscience and medicine.

Discovery of the EEG

On July 6, 1924, the psychiatrist Hans Berger conducted the first EEG recording on a humana 17-year-old boy undergoing neurosurgery. At the time, Berger and other researchers were conducting electrical recordings on the brains of animals.

What distinguished Berger was his obsession with physical basis of what he called psychic energyor mental effort, in humans. In a series of experiments spanning his early profession, Berger measured brain volume and temperature to check changes in mental processes similar to mental work, attention, and desire.

He then turned to recording electrical activity. Although he recorded the primary EEG traces within the human brain in 1924, Publication of results until 1929. These five intervening years were an agonizing period of self-doubt concerning the source of the EEG signal within the brain and of refining the experimental setup. Berger recorded lots of of EEGs on various subjects, including his own children, and experienced each experimental successes and setbacks.

Finally, he was convinced of his results and published a series of articles within the journal Archive for Psychiatry and hoped for a Nobel Prize. Unfortunately, the research community doubted his results and years passed before anyone else began using EEG in their very own research.

Berger was finally nominated for the Nobel Prize in 1940. But Nobel Prizes were not awarded this 12 months in every category as a result of World War II and the German occupation of Norway.

Neuronal oscillations

When many neurons are energetic at the identical time, generate an electrical signal strong enough to spread immediately through the conductive tissue of the brain, skull and scalp. EEG electrodes attached to the top can record these electrical signals.

Since the invention of the EEG, researchers have shown that neuronal activity oscillates at certain frequencies. In his first EEG recordings in 1924, Berger found that the predominant oscillatory activity was that which oscillated eight to 12 times per second, or 8 to 12 hertz, called Alpha vibrationsSince the invention of alpha rhythms, there have been many attempts to grasp how and why neurons oscillate.

It is believed that neuronal oscillations are essential for effective communication between specialized brain regions. For example, theta oscillations with a frequency of 4 to eight hertz are essential for communication between brain regions involved within the encoding and retrieval of memories in animals and humans.

The researchers then investigated whether or not they could alter neural oscillations and thereby influence the way in which neurons communicate with one another. Studies have shown that many behavioral and noninvasive methods can alter neural oscillations and result in changes in cognitive performance. Engaging in certain mental activities can trigger neural oscillations on the frequencies utilized by those mental activities. For example, my team's research found that Mindfulness meditation can increase theta frequency vibrations and improve memory recall.

Noninvasive methods of brain stimulation can goal frequencies of interest. For example, my team's ongoing research has shown that brain stimulation on the theta frequency result in improved memory recall.

EEG has also led to essential discoveries about how the brain processes information in many other cognitive domainsincluding how people perceive the world around them, how they focus their attention, how they convey through language and the way they process emotions.

Diagnosis and treatment of brain diseases

EEG is now widely used for diagnosis Sleep disorders and epilepsy and as a guide for the treatment of brain disorders.

Scientists are using EEGs to check whether memory could be improved through noninvasive brain stimulation. Although research continues to be in its infancy, there are already some promising results. For example, one study found that noninvasive brain stimulation at gamma frequency – 25 hertz – improved memory. Memory and neurotransmitter transmission in Alzheimer's disease.

A brand new variety of non-invasive brain stimulation, called temporal interference uses two high frequencies to generate neural activity equal to the difference between the stimulation frequencies. The high frequencies can higher penetrate the brain and reach the goal area. Researchers recently tested this method on humans by utilizing 2,000 hertz and a pair of,005 hertz to send 5 hertz theta frequencies to a vital brain region for memory, the hippocampus. This resulted in improvements in remember the name that’s related to a face.

Although these results are promising, further research is required to grasp the precise role of neural oscillations in cognition and to find out whether altering them can result in lasting improvements in cognition.

The way forward for the EEG

The one centesimal anniversary of the EEG provides a possibility to reflect on what it has taught us about how the brain works and what this technology can do in the long run.

In a survey For the journal Nature Human Behaviour, over 500 researchers who use EEG of their work were asked to make predictions concerning the way forward for the technology. What will likely be possible with EEG in the following 100 years?

Some researchers, including myself, predict that we are going to use EEGs to diagnose and goal brain diseases. Others consider that a affordable, portable EEG is widely used to enhance cognitive functions at home or is seamlessly integrated into virtual reality Applications. The possibilities are enormous.