Hans Berger (21 May 1873 – 1 June 1941)

  • German psychiatrist, worked as army psychiatrist during World War I and as Rector of Jena University.
  • Known for invention of electroencephalogram in 1924.
Contribution to Physiology

  1. Invention of recording electrical activity of the brain in humans, following the works of Richard Caton (1842–1926) in England with animals.
  2. Studied the connection between cerebral blood flow and neural activity, a critical relationship fundamental to modern functional brain imaging.
  3. Worked on lateralisation of brain along with other two scientists - Oskar Vogt (1870–1959) and Korbinian Brodmann (1868–1918).
  4. Discovery of alpha wave rhythm – known as “Berger’s wave” and its suppression (substitution by the faster beta waves) when the subject opens the eyes (also called alpha blockade).
  5. First to study the nature of EEG alterations in brain and disease such as epilepsy.
  6. Studied brain circulation, psychophysiology and brain temperature.

Basis for Hans Berger’s research – personal life experience

Hans Berger enlisted for a year of military service in Würzburg in 1892. During this period, Berger was involved in a bizarre incident that inspired his life-long search for a connection between mind and brain. One spring morning, while mounted on horseback and pulling heavy artillery for a military training exercise, Berger’s horse suddenly reared, throwing the young man to the ground on a narrow bank just in front of the wheel of an artillery gun. The horse-drawn battery stopped at the last second, and Berger escaped certain death with no more than a bad fright. That same evening, he received a telegram from his father, inquiring about his son’s well-being. Berger later learned that his older sister in Coburg was over- whelmed by an ominous feeling on the morning of the accident and she had urged their father to contact young Hans, convinced that something terrible had happened to him. He had never before received a telegram from his family, and Berger struggled to understand this incredible coincidence based on principles of natural science. There seemed to be no escaping the conclusion that Berger’s intense feelings of terror had assumed a physical form and reached his sister several hundred miles away—in other words, Berger and his sister had communicated by mental telepathy. Berger never forgot this experience, and it marked the starting point of a life-long career in psychophysics. His central theme became “the search for the correlation between objective activity in the brain and subjective psychic phenomena”.

Recorded first human EEG in 1924, filled with doubt it took him 5 years to publish his first paper in 1929. But he was completely ignorant of the technical and physical basis of his method. He knew nothing about mechanics or electricity. British electrophysiologists Edgar Douglas Adrian and B. H. C. Matthews confirmed Berger's basic observations in 1934.

His method involved inserting silver wires under the patients scalp, one at the front of the head and one at the back. Later he used silver foil electrodes attached to the head by a rubber bandage. As a recording device he first used the Lippmann's capillary electrometer, but results were disappointing. He then switched to the string galvanometer and later to a double-coil Siemens recording galvanometer, which allowed him to record electrical voltages as small as one ten thousandth of a volt. The resulting output, up to three seconds in duration, was then photographed by an assistant.