Mark Rosenzweig
Encyclopedia
Mark Richard Rosenzweig (September 12, 1922 – July 20, 2009) was an American
research psychologist who found in animal studies on neuroplasticity
that the brain
continues developing anatomically, reshaping and repairing itself into adulthood based on life experiences, overturning the conventional wisdom that the brain reached full maturity in childhood.
, to Jews of Eastern European origin, in which his bilingual parents (his lawyer father and homemaker mother spoke both English
and German
) helped foster an interest in language and learning. He attended the University of Rochester
there planning to major in history, but ended up switching to psychology and receiving a bachelor's degree in 1943 and a master's degrees in 1944 with a focus on auditory perception
.
Following the completion of his studies in 1944, he enlisted in the United States Navy
, initially serving as a radar technician at the Anacostia Naval Station. He was later relocated to Tsingtao
in China
, where he was stationed on the seaplane tender
USS Chincoteague
.
He attended Harvard University
after completing his military service in 1946, and was awarded a Ph.D.
in 1949. His thesis showed that the connections between the cochlea
and the cerebral cortex could be monitored using electrodes placed on the scalp, without requiring cranial surgery.
in 1949 as an assistant professorship in physiological psychology
, and remained on its faculty until he retired in the 1990s. Dissatisfied with existing textbooks in biological psychology, he and colleague Arnold Leiman wrote a textbook in the 1980s that is still in print.
Mark Rosenzweig initiated experimental research upon enriched environment
and the brain. Donald O. Hebb, in 1947, had found that rats raised as pets performed better on problem solving tests than rats raised in cages. But his research did not investigate the brain directly nor use standardized impoverished and enriched environments. Mark Rosenzweig with his colleagues David Krech, Edward Bennett and Marian Diamond started this research in the late 1950s by comparing single rats in normal cages, and those placed in ones with toys, ladders, tunnels, running wheels in groups. They found that growing up in enriched environments affected activity of the enzyme cholinesterase
in the brain. This work led in 1962 to the discovery that environmental enrichment increased cerebral cortex
volume. He published details of his research in a book Enriched and Impoverished Environments: Effects on Brain and Behavior in 1987.
These findings contradicted the prevailing scientific theory that the brain's structure was fixed before adulthood and that later learning and experience did not affect its structure. Later research confirmed that the changes occurred in adulthood and were not tied to differences in diet. Neurobiologist James McGaugh
credited Rosenzweig's research with having "laid to rest the idea that the brain is fixed in terms of its composition; that's now regarded as nonsense" with the subject of research changing to how, not if, the brain changes based on experience.
Rosenzweig retired from UC Berkeley in 1991. The American Psychological Association
recognized him with its Distinguished Scientific Contribution Award in 1982.
, Rosenzweig died at his home at age 86 of renal failure
on July 20, 2009. He was survived by two daughters, a son, six grandchildren and two great-grandchildren. He married his French-born wife, the former Janine Chappat, in the summer of 1947. She had studied anthropology and education at the University of Oxford
and had been visiting the United States when they met. She died in April 2008 after they had been married for 60 years.
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
research psychologist who found in animal studies on neuroplasticity
Neuroplasticity
Neuroplasticity is a non-specific neuroscience term referring to the ability of the brain and nervous system in all species to change structurally and functionally as a result of input from the environment. Plasticity occurs on a variety of levels, ranging from cellular changes involved in...
that the brain
Brain
The brain is the center of the nervous system in all vertebrate and most invertebrate animals—only a few primitive invertebrates such as sponges, jellyfish, sea squirts and starfishes do not have one. It is located in the head, usually close to primary sensory apparatus such as vision, hearing,...
continues developing anatomically, reshaping and repairing itself into adulthood based on life experiences, overturning the conventional wisdom that the brain reached full maturity in childhood.
Early life and education
Rosenzweig was born on September 12, 1922, in Rochester, New YorkRochester, New York
Rochester is a city in Monroe County, New York, south of Lake Ontario in the United States. Known as The World's Image Centre, it was also once known as The Flour City, and more recently as The Flower City...
, to Jews of Eastern European origin, in which his bilingual parents (his lawyer father and homemaker mother spoke both English
English language
English is a West Germanic language that arose in the Anglo-Saxon kingdoms of England and spread into what was to become south-east Scotland under the influence of the Anglian medieval kingdom of Northumbria...
and German
German language
German is a West Germanic language, related to and classified alongside English and Dutch. With an estimated 90 – 98 million native speakers, German is one of the world's major languages and is the most widely-spoken first language in the European Union....
) helped foster an interest in language and learning. He attended the University of Rochester
University of Rochester
The University of Rochester is a private, nonsectarian, research university in Rochester, New York, United States. The university grants undergraduate and graduate degrees, including doctoral and professional degrees. The university has six schools and various interdisciplinary programs.The...
there planning to major in history, but ended up switching to psychology and receiving a bachelor's degree in 1943 and a master's degrees in 1944 with a focus on auditory perception
Hearing (sense)
Hearing is the ability to perceive sound by detecting vibrations through an organ such as the ear. It is one of the traditional five senses...
.
Following the completion of his studies in 1944, he enlisted in the United States Navy
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
, initially serving as a radar technician at the Anacostia Naval Station. He was later relocated to Tsingtao
Qingdao
' also known in the West by its postal map spelling Tsingtao, is a major city with a population of over 8.715 million in eastern Shandong province, Eastern China. Its built up area, made of 7 urban districts plus Jimo city, is home to about 4,346,000 inhabitants in 2010.It borders Yantai to the...
in China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
, where he was stationed on the seaplane tender
Seaplane tender
A seaplane tender is a ship that provides facilities for operating seaplanes. These ships were the first aircraft carriers and appeared just before the First World War.-History:...
USS Chincoteague
USS Chincoteague (AVP-24)
USS Chincoteague was a United States Navy seaplane tender in commission from 1943 to 1946.-Construction and commissioning:Chincoteague was launched on 15 April 1942 by Lake Washington Shipyard at Houghton, Washington, sponsored by Mrs. G. Rowe. She was commissioned on 12 April 1943 with Commander...
.
He attended Harvard University
Harvard University
Harvard University is a private Ivy League university located in Cambridge, Massachusetts, United States, established in 1636 by the Massachusetts legislature. Harvard is the oldest institution of higher learning in the United States and the first corporation chartered in the country...
after completing his military service in 1946, and was awarded a Ph.D.
Ph.D.
A Ph.D. is a Doctor of Philosophy, an academic degree.Ph.D. may also refer to:* Ph.D. , a 1980s British group*Piled Higher and Deeper, a web comic strip*PhD: Phantasy Degree, a Korean comic series* PhD Docbook renderer, an XML renderer...
in 1949. His thesis showed that the connections between the cochlea
Cochlea
The cochlea is the auditory portion of the inner ear. It is a spiral-shaped cavity in the bony labyrinth, making 2.5 turns around its axis, the modiolus....
and the cerebral cortex could be monitored using electrodes placed on the scalp, without requiring cranial surgery.
University of California, Berkeley
He was hired by the University of California, BerkeleyUniversity of California, Berkeley
The University of California, Berkeley , is a teaching and research university established in 1868 and located in Berkeley, California, USA...
in 1949 as an assistant professorship in physiological psychology
Physiological psychology
Physiological psychology is a subdivision of behavioral neuroscience that studies the neural mechanisms of perception and behavior through direct manipulation of the brains of nonhuman animal subjects in controlled experiments...
, and remained on its faculty until he retired in the 1990s. Dissatisfied with existing textbooks in biological psychology, he and colleague Arnold Leiman wrote a textbook in the 1980s that is still in print.
Mark Rosenzweig initiated experimental research upon enriched environment
Environmental enrichment (neural)
Environmental enrichment concerns how the brain is affected by the stimulation of its information processing provided by its surroundings . Brains in richer, more stimulating environments, have increased numbers of synapses, and the dendrite arbors upon which they reside are more complex...
and the brain. Donald O. Hebb, in 1947, had found that rats raised as pets performed better on problem solving tests than rats raised in cages. But his research did not investigate the brain directly nor use standardized impoverished and enriched environments. Mark Rosenzweig with his colleagues David Krech, Edward Bennett and Marian Diamond started this research in the late 1950s by comparing single rats in normal cages, and those placed in ones with toys, ladders, tunnels, running wheels in groups. They found that growing up in enriched environments affected activity of the enzyme cholinesterase
Cholinesterase
In biochemistry, cholinesterase is a family of enzymes that catalyze the hydrolysis of the neurotransmitter acetylcholine into choline and acetic acid, a reaction necessary to allow a cholinergic neuron to return to its resting state after activation.-Types:...
in the brain. This work led in 1962 to the discovery that environmental enrichment increased cerebral cortex
Cerebral cortex
The cerebral cortex is a sheet of neural tissue that is outermost to the cerebrum of the mammalian brain. It plays a key role in memory, attention, perceptual awareness, thought, language, and consciousness. It is constituted of up to six horizontal layers, each of which has a different...
volume. He published details of his research in a book Enriched and Impoverished Environments: Effects on Brain and Behavior in 1987.
These findings contradicted the prevailing scientific theory that the brain's structure was fixed before adulthood and that later learning and experience did not affect its structure. Later research confirmed that the changes occurred in adulthood and were not tied to differences in diet. Neurobiologist James McGaugh
James McGaugh
James L. McGaugh is an American neurobiologist working in the field of learning and memory. He is currently a Research Professor at the University of California, Irvine....
credited Rosenzweig's research with having "laid to rest the idea that the brain is fixed in terms of its composition; that's now regarded as nonsense" with the subject of research changing to how, not if, the brain changes based on experience.
Rosenzweig retired from UC Berkeley in 1991. The American Psychological Association
American Psychological Association
The American Psychological Association is the largest scientific and professional organization of psychologists in the United States. It is the world's largest association of psychologists with around 154,000 members including scientists, educators, clinicians, consultants and students. The APA...
recognized him with its Distinguished Scientific Contribution Award in 1982.
Personal
A resident of Berkeley, CaliforniaBerkeley, California
Berkeley is a city on the east shore of the San Francisco Bay in Northern California, United States. Its neighbors to the south are the cities of Oakland and Emeryville. To the north is the city of Albany and the unincorporated community of Kensington...
, Rosenzweig died at his home at age 86 of renal failure
Renal failure
Renal failure or kidney failure describes a medical condition in which the kidneys fail to adequately filter toxins and waste products from the blood...
on July 20, 2009. He was survived by two daughters, a son, six grandchildren and two great-grandchildren. He married his French-born wife, the former Janine Chappat, in the summer of 1947. She had studied anthropology and education at the University of Oxford
University of Oxford
The University of Oxford is a university located in Oxford, United Kingdom. It is the second-oldest surviving university in the world and the oldest in the English-speaking world. Although its exact date of foundation is unclear, there is evidence of teaching as far back as 1096...
and had been visiting the United States when they met. She died in April 2008 after they had been married for 60 years.