What was EEG invented with?

British doctor Richard? Caton first observed brain waves in animals in 1875. Because of William? Inspired by Einstein's successful invention of electrocardiogram, German medical scientist Hans? Berger decided to use a string galvanometer to measure the electrical activity of the brain. Beagle first exposed the surface of the dog's brain and measured the current outside the dog's brain. Later, taking the opportunity of craniotomy for patients, needle electrodes were inserted under the scalp for experiments. Finally, the complete skull function of normal people and brain patients was tested and achieved success. He named the method of recording human EEG as EEG, which became the beginning of clinical application of EEG.

Berger was the first person to identify two different types of brain waves. He found that when people are thinking, resting and sleeping, EEG shows different patterns.