Marian Diamond est la première scientifique à avoir pu disséquer le cerveau d'Einstein. Elle est la pionnière des neurosciences. © Berkeley University

What does science owe to Marian Diamond, the woman who dissected Einstein’s brain?

Marian Diamond is a name that few people know today. However, her contribution is not the least: she is the first to demonstrate 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 examine Albert Einstein’s brain after his death.

You will also be interested

[EN VIDÉO] Observation of a human brain
The Institute of Human Anatomy uses human cadavers as tools for teaching anatomy and for medical device training and prototype testing.

Marian Diamond was born on November 11, 1926 in Glendale, California. She is the daughter of Rosa Marian Whampler, a Latin teacher at Berkeley High School, and Dr. Montague Cleeves, a physician at Los Angeles County Hospital. At the age of 15, when she follows her father through the corridors of the hospital where he works, she sees through a crack Goal a scene that will determine the rest of his life. Four men are standing around a table on which is placed a jar with brain function
The brain is located in the cranial box and is the seat of higher (cognitive functions, senses, nerve reactions) and vegetative functions. It is therefore an essential organ that regulates everything…” data-image=” .jpg” data – url=”” data-more=”Read more”>Brain was laid.

She doesn’t know what they’re doing, but her attention is drawn to the inanimate organ resting in its fluid. Do all our thoughts come from there? That little building of cells you can hold in one hand? Marian is overwhelmed by the complexity and mystery of this matter Brain person she meets for the first time. It is the beginning of a love story that will only end with his last breath.

Marian went to the University of Berkeley, where she received her degree in biology at the age of 21, and then spent a summer at the University of Oslo. Back to his alma mater, she works on her doctoral thesis and at the same time begins to teach, a passion that will never leave her. In 1953 she became the first woman to graduateanatomy in the history of the university, the triumphant survivor of a promotion by an overwhelming majority of 100 men for 5 women. Now officially a Doctor of Human Anatomy, Marian now hopes to dedicate herself fully to studying the human brain. But his disillusionment is bitter. Marian cannot be disassembled.

Emergence of a new discipline

Towards the end of the 1950s, she discovers an experience that will give her an idea. In this study, the researchers analyzed the brains of rats that had learned to navigate mazes and revealed the levels of acetylcholinesterase, a chemical messenger that enables neurons to communicate
Each neuron consists of:
a cell body or perikaryon containing the nucleus; very many dendritic branches (therefore …” data-image=” /8/4/4845b46c32_50034180_neuron -dr.jpg” data-url=”” data-more=”Read more”>neurons, are much higher there than in the brains of control rats. The result is surprising, but the anatomist does not go far enough.

At the time, that was the dominant idea the brain is an organ whose structure is genetically predetermined and immutable once you reach adulthood. But another conviction gradually grips Marian. What if our brains changed as a result of our experiences and interactions throughout our lives?

To be sure, she contacted one of the study’s authors, psychologist Mark Rosenzweig, and asked to join his team, which consisted of another psychologist, David Krech, and chemist Edward Bennett. In just a few years, the four researchers have set up a groundbreaking experiment that opens up a new field of The neurologist uses it to treat a variety of pathologies, be they…” data-image=”https://cdn. futura-sciences .com/buildsv6/images/midioriginal/b/d/2/bd2ecba368_43430_cerveau-4.jpg” data-url=”” data-more=”Read more”>neurology.

How to prove the plasticity of the brain?

To assess the effects of the environment on brain anatomy, they created three groups of male rats from the same lineage, thereby limiting the risk of variation genetically. A first is placed in so-called enriched cages, where the rodents can interact with each other and have ladders to explore and wheels to practice on; a second is placed in an impoverished environment where the rat is alone in a bare cage; and finally, a third serves as a control group in which the rats are seated together with no toys to stimulate them.

After 80 days, the rats’ brains are prepared, cut into very thin strips and analyzed microscope. The result is clear: the brain: the cerebral cortex, which is located under the meninges; the kidney: the renal cortex is the…” data-image=” /images/midioriginal/0/7/9/0795c9d4a3_105668_cortex-definition-01.jpg” data- url=”” data-more=”Read more” >cortex Rats from the enriched state are 6% fatter than those of rodents raised in deflated cages and their ratio of glial cells per neuron is more important. Marian and her colleagues have just demonstrated, for the very first time, the existence of what we call today neuroplasticityand to highlight the hitherto unimagined importance of glial cells in theTo learn. After Several replicationsthe study was eventually published in the journal Science.

What was Marian Diamond carrying in her hat box?

Marian still faces many prejudices, especially now that the publication of her study has shattered beliefs at the time in the immutability of the brain, but she continues to defend her work with patience and objectivity. A teacher adored by her students, we regularly see her going to and returning from amphitheaters with a hatbox in hand. It hides in an authentic brain that she likes to show off to her students at the beginning of the year.

In 1984, Marian’s Berkeley office became the sanctuary of another container with unusual contents: the mayonnaise jar sent by Thomas Harvey containing 4 fragments of Albert’s brain Einstein.

The circumstances surrounding the acquisition of this strange relic are debatable, to say the least. Because the instructions that the famous scientist left behind when he died were crystal clear: Cremate my body and secretly scatter my ashes because I do not wish to be idolized.

Disobedience that sheds light on science

It’s Thomas Harvey, in charge of the purpose of an autopsy
The purpose of an autopsy is to pinpoint a victim’s causes of death. They are also practiced by medical students to learn human anatomy.
Unfolding of a…” data-image=”” data-url = ”” data-more=”Read more”>autopsy of the deceased physicist, does not intend to respect these wishes. He deprives the body entrusted to him of everything he can, including his internal organs, his Eyes, which he sends to Einstein’s ophthalmologist and his brain, which he keeps at home; then he sends the remains to the authorities responsible for his cremation. However, the theft is quickly noticed and Princeton Hospital immediately fires Harvey.

For their part, Einstein’s family points the finger at the sacrilegious act committed by the family pathologist, and only reluctantly the scientist’s son finally allows Harvey to keep the brain. He hastily cuts it into 240 small pieces, which he preserves in celloid, and apart from a few shipments to scientists around the world, Albert Einstein’s strained brain rested in various jars and boxes and gathered dust in Harvey’s basement for 40 years.

What does the dissection of Einstein’s brain show?

Thankfully, Marian has no intention of leaving those pink chunks of meat in her jar. The preservation method used by Harvey is exactly what he needs: it will be able to as with the brain Rats, cut the physicist’s cerebral cortex into thin slices and observe in detail the distribution of the cells that make it up. She turns her attention to the role of the prefrontal cortex in depression
The prefrontal cortex plays a…” data-image=”” data-url=”https:/ /” data-more=”Read more”>prefrontal cortex upper and lower parietal of the left and right hemispheres, and then compares the results to identical regions taken from 11 male human brains.

Conclusion: Area 39, known as Brodmann’s area, shows a larger number of glial cells, more precisely structures of astrocytes
Astrocytes have a star shape, the cytoplasmic processes of which can be short, but very numerous, or, on the contrary, long and less branched.
role of astrocytes
Astrocytes have…” data-image=”” data-url=”https:/ /” data-more=”Read more”>astrocytesresponsible for the maintenance and repair of neurons and oligodendrocytes involved in their proper communication.

The study is the first to look at Einstein’s brain, but its findings will remain controversial, as will those of subsequent studies. It is difficult to interpret with certainty the analyzes performed on a brain that has been dead for nearly 30 years and to find other brains of relatively similar age and health to compare it to.

Although the general public now remembers Marian Diamond as the woman who dissected Einstein’s brain, it was her experiment on rats that elevated her to the ranks of the great scientists of the last century. Marian taught at Berkeley until the age of 80, and actually became one a star on youtube, where his courses are broadcast by the university. She died on July 25, 2017 at the age of 90. History doesn’t tell us if his brain was bequeathed to science.

Interested in what you just read?

#science #owe #Marian #Diamond #woman #dissected #Einsteins #brain

Leave a Comment

Your email address will not be published.