Welcome to Kelly’s first article of her science series, where she’ll be covering everything relating to science and the recent breakthroughs happening in the field! (Images are cited or found using Creative Commons)
Einstein’s brain has always been a source of mystery, even 65 years after his death. Some speculated that his genius may have been the result of having a bigger brain, or perhaps it was a combination of his upbringing and environment, but there is one often overlooked aspect that contributed to his intelligence: glial cells.
When Einstein passed away in 1955, at Princeton Hospital in New Jersey, Dr. Thomas Harvey performed an autopsy on Einstein. During the procedure, he removed the brain and examined it. However, he did not place the brain back in the skull, but instead placed it into a jar of formaldehyde to preserve it. From there, he made off with the brain, justifying the action by calling it “a sense of duty to science”.
Flash forward forty years, and a writer by the name of Paterniti has become interested in Einstein’s brain. Paterniti called up a now eighty year old Harvey to join him in delivering the brain back to Einstein’s granddaughter Evelyn, who lived in California. When Paterniti arrived at Harvey’s home, he saw him emerge from the house with Einstein’s brain stashed in a tupperware. The two started the long drive to California, while Harvey explained how he had taken various photographs of Einstein’s brain (one of which is shown below) and sent portions of it to various neuroscientists across the country. What Harvey had in the tupperware was a smaller and sliced up portion of the original brain.
One Berkeley scientist who was interested in doing research, Marian Diamond, asked Harvey to send portions from four different areas in the brain. Harvey agreed, but Diamond didn’t receive anything for the next few months. Three years later, she finally received slices of the brain tissue in a mayonnaise jar.
At this point in time, most people believed that all the important work in the brain was done by neurons. Diamond wanted to use a new approach to study Einstein’s brain: by analyzing the glia. When examining Einstein’s brain, what she found was that his brain had higher numbers of glia than the average brain. Glia’s name comes from the word “glue”, because most people just thought a glial cell’s only job was to hold neurons together. This would all change in 1990, when Dr. Steven Smith made a discovery.
Glia: the other half of the brain
Dr. Smith, a Stanford researcher, published a groundbreaking paper in the Science journal that detailed the role of glia. He knew that neurons communicate by sending electrical and chemical signals from dendrites down to the axons, which in turn are connected to other dendrites. Smith suspected astrocytes, a type of glia, were also sending signals of their own, but in chemical form, which is a lot harder to detect than electrical signals. What’s more, he believed that glia were actually “eavesdropping” on the chemical signals in neurons, and sending these signals to other distant parts of the brain, allowing for messages to be broadcast. Smith immediately created an experiment to test if this was true. Using astrocytes taken from a mouse, he placed them in a petri dish, and pipetted a neurotransmitter (glutamate, a chemical messenger often used by neurons) into the dish. On a computer screen, the astrocytes lit up. Within moments, waves of color radiated out from the contact point, thus showing that glia, like neurons, also communicated with each other. This was a revolutionary discovery; glia was no longer just non-functional glue, it also played a pivotal role in sending messages throughout the brain.
A picture of an astrocyte. (Accessed from Wikimedia Commons)
If Einstein had more glia than the average brain, and glia enhanced the brain’s ability to pass along messages, does that mean glia are the new genius cell? The truth is, we don’t know enough about glia to answer that question. However, this discovery helped us to better understand how Einstein’s brain worked, and helped scientists to get a better idea of his genius.