Marian Diamond — led pivotal studies of developing brain
Marian Cleeves Diamond, a UC Berkeley neuroscientist famed for her groundbreaking studies of the developing brain, died July 25 at her home in Oakland. She was 90.
In experiments that began more than 60 years ago, Professor Diamond and her colleagues showed for the first time that enriching the early environment of lab rats could alter their brain anatomy and significantly improve their ability to learn.
Applied to humans, their pioneering discoveries led to major improvements in the education of children from infancy on, and have established the plasticity of the brain, meaning it is subject to growth or attrition by the nature of its environment.
Professor Diamond became something of a celebrity in 1984 when she was asked to examine preserved slices of Albert Einstein’s brain and found that they contained significantly more glial cells than in the average human brain. Some scientists now believe that those glial cells play a role in developing the human imagination.
But her work with rats was by far the most significant because it proved that the brain can change with outside influences.
“Her research demonstrated the impact of enrichment on brain development — a simple but powerful new understanding that has literally changed the world, from how we think about ourselves to how we raise our children,” UC physiologist George Brooks said in a commentary on her life.
In the late 1950s and early 1960s, Professor Diamond and her colleagues raised hundreds of laboratory rats in caged environments. They furnished some cages with toys and mazes and wheels for running, or with other rats as companions. But in many others, the rats lived alone or in impoverished cages with no toys and no companions.
Through these experiments, Professor Diamond showed that an enriched environment clearly led to improved brain structure and learning ability in the growing rats, while impoverished environments meant smaller and duller rat brains.
Her colleagues in those years of work were Berkeley psychologists David Krech and Mark Rosenweig, and Edward Bennet, a graduate student in the laboratory of Nobel laureate Melvin Calvin.
“Dr. Diamond showed anatomically, for the first time, what we now call plasticity of the brain,” Brooks said. “In so doing, she shattered the old paradigm of understanding the brain as a static and unchangeable entity that simply degenerated as we age.”
In her research, Professor Diamond showed that the brain can continue developing in old age, that growth and learning can continue through life. She also established that the male and female cerebral cortex are structured differently. Experimenting with bridge players, she showed that stimulating the brain can enhance the human immune system.
She continued her research and teaching at Berkeley until she retired as a professor of integrated biology three years ago at the age of 87. Her entire UC course on human anatomy is still carried on YouTube. An award-winning documentary film, “My Love Affair With the Brain: The Life and Science of Dr. Marian Diamond,” is also available on YouTube.
Her book, “Magic Trees of the Mind: How to Nurture Your Child’s Intelligence, Creativity, and Healthy Emotions from Birth Through Adolescence,” was cowritten by science writer Janet Hopson.
She was born in Glendale (Los Angeles County) in 1926 and graduated from UC Berkeley in 1946 after earning her Cal letter on the tennis team. After researching and teaching at Harvard and Cornell between 1952 and 1958, she moved to UCSF, where she taught human biology and anatomy to medical students. In 1960, she returned to UC Berkeley as a lecturer.
Professor Diamond is survived by her daughters, Catherine of Taiwan and Ann of Mazama, Wash.; and sons, Richard and Jeff of Berkeley. Her husband of 35 years, Arnold Scheibel, a leading neuroscientist at UCLA, died April 3. Her first husband, the late Richard M. Diamond, was a nuclear chemist at the Lawrence Berkeley National Laboratory.
A private service is planned.