- Written by Victor Parachin Victor Parachin
Sometime during the Neolithic or Stone Age (6000–2000 BCE), a girl who suffered from epilepsy, migraines, depression, or a mental illness was treated by someone skilled in trepanation.
Using tools available at the time, that person carefully made an incision on the scalp, peeling the skin back, and then drilled a hole in the girl’s skull in order to bring relief from her condition.
Amazingly, the girl survived this prehistoric form of neurosurgery. Currently, her trepanated skull is displayed at the Museum of Natural History in Lausanne, Switzerland.
Today, neurosurgeons continue to perform similar operations—still called trepanation—to relieve pressure on the brain or to remove bone fragments.
From the Neolithic age right to our own modern times, humans have worked hard to understand the complexities of the brain. It has been quite a learning curve, filled with errors and corrections followed by more misconceptions and revisions. Here is a brief history of the brain.
Aristotle’s confusions. Though the famed Greek philosopher (384–322 BCE) was Plato’s most famous student, tutor to Alexander the Great, and founder of his own prestigious university, his medical knowledge was flawed.
He believed and taught that “the brain is an organ of minor importance” and that “the seat of the soul and the control of voluntary movement—in fact, of nervous functions in general—are to be sought in the heart.”
Though he was wrong, his position is somewhat defensible in that Aristotle observed an injury to the heart meant immediate death, whereas a head injury brought trauma but could heal.
Hippocrates’ corrections. Regarded as the founder of Western medicine, Hippocrates (460–377 BCE) correctly identified the brain as the driving force of the central nervous system.
One of history’s most famous physicians, Hippocrates rejected superstition in favor of scientific observation, teaching that diseases had explainable causes and were not punishments from the gods.
He identified the brain as the source of human emotions: “Men ought to know that from the brain, and from the brain only, arise our pleasures, joy, laughter, and jests, as well as our sorrows, pains, griefs, and tears.”
Hippocrates recognized brain complexity, noting that an illness, trauma, or damage to the brain was dangerous and could be deadly.
He also correctly noted that the brain controls all senses and movements; the brain is the seat of intelligence; and paralysis occurs on the side of the body opposite the side of a head injury.
Autopsies and dissections are condemned. Herophilus (330–280 BCE) was a Greek physician who is regarded as the world’s first anatomist. He was founder of the world-famous Medical School of Alexandria and is the first known person to systematically perform scientific dissections on human cadavers.
Herophilus was a skilled scientist who carefully recorded his findings, eventually writing nine medical volumes. In those, he described various bodily organs, compared the human brain to the brains of animals, and was the first to distinguish sensory and motor nerves.
However, as he and other physicians opened and studied cadavers, the practice became suspect, controversial, and condemned.
Influential Christian theologian Tertullian (160–225 CE) referred to Herophilus not as a doctor but as a “butcher who cut up innumerable corpses in order to investigate nature and who hated mankind for the sake of knowledge.”
Tertullian’s condemnation of autopsies and dissections meant fewer and fewer physicians were willing to examine cadavers. Eventually, it became illegal in the Roman Empire to dissect human bodies. This would impede anatomical and medical knowledge for centuries.
Galen the anatomist. The first person to seriously study the brain was Claudius Galen (129–199 CE), a Roman physician. His medical and anatomical knowledge combined with his huge collection of writings made him a foundational figure in Western medicine for over a thousand years.
Galen’s writings include the 17-volume On the Usefulness of the Parts of the Human Body. His collected works total 22 volumes.
Because of opposition to dissecting human cadavers, Galen used pigs, goats, dogs, and monkeys, carefully studying their anatomy. Operating on live animals, he conducted spinal cord experiments showing how severing the spinal cord at various places affected different parts of the body.
Studying animal brains, Galen correctly identified various cranial nerves, such as the optic nerve (sight and visual information), the olfactory nerve (smell and taste), the acoustic nerve (hearing and balance), and the oculomotor nerve (eye movement control).
The slow birth of neurology. Because the church banned dissection of cadavers, the progress of brain anatomy and knowledge moved slowly during the Middle Ages (fifth through 15th centuries).
This changed during the Renaissance era, when philosophers and artists such as Leonardo da Vinci became curious about anatomy, particularly the brain. Da Vinci produced a series of anatomical drawings that included considerable detail about the brain.
Following his lead, British physician and emerging neuro-anatomist Thomas Willis (1621–75) began to examine and study brains extensively. In 1664 he published a groundbreaking book, Cerebri Anatome, complete with intricate information about major brain regions and the functions of some cranial nerves.
In the 19th century, French surgeon Paul Pierre Broca (1824–1880) conducted numerous autopsies carefully examining human brains. He correctly noted that the frontal lobes were instrumental in driving intellect, judgment, abstract thinking, and critical reasoning.
The strange case of Phineas Gage. A great deal of brain knowledge has come by studying people who have had damage to various regions of the brain. One of the most amazing and fascinating cases is that of Phineas Gage.
In 1848, Gage worked on a railroad construction crew. As he was setting a charge of explosives, the dynamite blew prematurely, propelling a 13-pound, 3.5-foot iron bar through the front of his head, where it destroyed much of his frontal cortex.
Despite this appalling injury, Gage did not lose consciousness but walked calmly to a road where he obtained a ride into town. There a physician managed to remove the rod.
Though Gage survived this trauma, he was never the same. Before the accident, friends described him as responsible, hardworking, intelligent, and friendly.
Afterward, his personality changed, leaving him unstable and impulsive. He wandered from job to job, eventually traveling with carnivals and exhibiting himself and his iron bar. Gage developed epilepsy and died 13 years later.
Nevertheless, the report of Gage’s change in personality confirmed studies of other neurologists that psychopathological conditions could be correlated to brain injury.
Einstein’s brain. Regarded as one of the most prominent geniuses of the 20th century, Albert Einstein’s brain was removed within eight hours of his death on April 18, 1955, in Princeton, New Jersey.
Physician Thomas Harvey performed the autopsy with the approval of Einstein’s son, who stipulated that his father’s brain should be used only for research to be published in scientific journals of “high standing.”
vHarvey sliced the brain into sections, providing some samples to leading pathologists but keeping many for himself. In 1978 a reporter (Steven Levy) interviewing Harvey learned the doctor still had several sections of Einstein’s brain.
His published story attracted interest from scientists, who began to carefully scrutinize it. They discovered that Einstein’s brain was smaller than average, weighing 1,230 grams rather than the normal 1,400.
However, his parietal lobes were unusually large, and this part of his brain was 15 percent wider than other human brains. The parietal lobes are where mathematical thought emerges, thus offering one explanation for Einstein’s incredible mathematical powers.
Though brain science has developed greatly in recent times, it is still a frontier waiting to be further explored.
Douglas Tweed, author of Microcosms of the Brain, notes: “Present-day knowledge of the brain resembles in some ways earlier Europeans’ knowledge of Africa. Explorers have mapped the coastline in detail, but the interior is mostly uncharted.”