Marian Diamond is a name that few people know today. However, her contribution is no less: she is the first to prove the existence of neuroplasticity, the ability of the brain to change its morphology according to experiences and the environment. She is also the first person to study Albert Einstein’s brain after his death.
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Marian Diamond was born on November 11, 1926 in Glendale, California. She is the daughter of Rosa Marian Wampler, a Latin teacher at Berkeley High School, and Dr. Montague Cleaves, a physician at Los Angeles County Hospital. At the age of fifteen, as she follows her father through the corridors of the hospital where he works, she sees through a crack Gate A scene that will define the rest of his life. Four men standing around a table with an urn in it brain He was placed.
She doesn’t know what they’re doing, but her attention is focused on the lethargic organ that lies in his fluid. Is this where all our thoughts come from? Who is this little edifice of cells capable of grasping with one hand? Marianne is overwhelmed by the complexity and mystery of this brain The person you meet for the first time. It is the beginning of a love story that will only end with his last breath.
Marianne attended Berkeley University where she earned her degree in biology at the age of 21, and then spent the summer at the University of Oslo. Back to his site alma mater, working on her doctoral thesis and at the same time starting to teach, a passion that will never leave her. In 1953, she became the first woman to graduate from itanatomy In the history of the university, the victorious survivor of the promotion that counts the overwhelming majority of 100 men against 5 women. Now Marianne is a doctor in human anatomy, and now hopes to be able to devote herself entirely to the study of the human brain. But his disappointment is bitter. Marianne does not allow herself to be disassembled.
Creation of a new specialty
Towards the end of the 1950s, she discovered an experiment that would give her an idea. In this study, researchers analyzed the brains of mice that had learned to navigate mazes and revealed that levels of acetylcholinesterase, a chemical transporter that allows communication between nervous cells, significantly higher than in the brains of control mice. The result was surprising, but it was not enough for the anatomist.
At that time, the prevailing idea was that the brain It is a genetically determined member Fixed Once you reach adulthood. But another belief gradually took hold of Marianne. What if our brain changed throughout our lives, based on our experiences and interactions?
To make sure, I called one of the study’s authors, psychologist Mark Rosenzweig, and asked to join his team, made up of another psychologist, David Kreich, and chemist Edward Bennett. In a few years, the four researchers conducted a groundbreaking experiment that will open up a new field of Neurology.
How to prove the softness of the brain?
In order to assess the effect of environment on brain anatomy, they generated three groups of male mice of the same breed, thus reducing the risk of variation. hereditary. The first is placed in the so-called fertilized cages, where rodents They can interact with each other and have ladders to explore and wheels to practice on; the second is placed in a poor environment where the rat is alone in a bare cage; Finally, the third group acts as a control group, where the mice are placed together, without toys to stimulate them.
After 80 days, the mice’s brains are dissected, cut into very thin slices, and analyzed microscope. The result is clear: Dandruff Mice from the fertilization condition are 6% thicker than rodents raised in depleted cages, and a proportion of glial cells Each neuron is more important. Marianne and her colleagues have just demonstrated for the first time the existence of what we now call neuroplasticityand to highlight the unexpected importance of glial cells inlearning. after several repetitionsThe study was recently published in the journal Science.
What was Marianne Diamond carrying in her little box?
Marianne still has to contend with a lot of bias, especially now that the publication of her study has shaken up then-held beliefs about the immutability of the brain, but she continues to defend her work patiently and objectively. A teacher who is adored by her students, we regularly see her going to the stands or coming back from her with a small box in her hand. She hides inside an authentic mind that she loves to present to her students at the beginning of the year.
In 1984, Marian’s office in Berkeley became home to another container with unusual contents: a jar of mayonnaise sent by Thomas Harvey, which contained 4 parts of Albert’s brain. Einstein.
The conditions for obtaining this strange effect are controversial to say the least. After all, the instructions that the famous scientist left at his death were quite clear: I burn my body and scatter gray in secret because I do not wish to be an idol.
The disobedience that sheds light on science
But Thomas Harvey, responsible forcorpse dissection from the deceased physical, do not intend to respect these wishes. He extracts everything he can from the body entrusted to him, including his internal organs eyes, which he sends to Einstein’s ophthalmologist and whose brain he keeps at home; Then he sends the remains to the departments charged with cremation. However, the theft was soon noticed, and Princeton Hospital shot Harvey on the spot.
The Einstein family, for their part, pointed the finger at the sacrilegious act committed before pathologistAnd only reluctantly did the scientist’s son allow Harvey to preserve the brain. This one is quick to chop it up into 240 tiny pieces that he keeps in silico, and apart from a few shipments to scientists around the world, Albert Einstein’s brain ends up resting for 40 years in various cans and boxes, gathering dust in a Harvey vault.
What reveals the anatomy of Einstein’s brain?
Fortunately, Marianne doesn’t intend to leave these bits of pink flesh in her jar. The method of memorization that Harvey uses is exactly what he needs: he will be able, as with the brain Mice, cut the cortex of the physicist into thin slices and observe in detail the distribution of the cells that make up it. focus her attention on prefrontal cortex superior and inferior parietal of the right and left hemispheres and then compares the results with identical regions taken from 11 male human brains.
Conclusion: Region 39, known as Brodmann’s region, has the highest number of glial cells in the world, more specifically stellateresponsible for supplying and repairing neurons and oligodendrocytes that are involved in their proper connections.
The study is the first to look at Einstein’s brain, but its results will remain controversial, as will those of the studies that will follow. It is difficult to interpret analyzes of a brain that has been dead for nearly 30 years with certainty, and to find other brains of the same age and relatively healthy to compare with them.
Although the general public today remembers Marianne Diamond as the woman who explained Einstein’s brain, it was her experience with mice that elevated her to the status of great scientists of the last century. Marianne continued teaching at Berkeley until the age of 80 and until she became star on youtubeWhere the university broadcasts its courses. She passed away on July 25, 2017, at the age of 90. History does not tell us whether his brain was bequeathed to science.
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