# Michael Gazzaniga

Michael S. Gazzaniga (born December 12, 1939) is an American cognitive neuroscientist who is an emeritus professor of psychology at the University of California, Santa Barbara. He is the founder and retired director of the SAGE Center for the Study of the Mind at UCSB (2006–2023).

## Biography

In 1961, Gazzaniga graduated from Dartmouth College with a B.A in Zoology. In 1964, he received a Ph.D. in psychobiology from the California Institute of Technology, where he carried out research on human split-brain patients for his doctoral thesis under Roger Sperry. In his subsequent work he has made important advances in our understanding of which functions are lateralized in the brain and how the left and right cerebral hemispheres communicate with one another.

## Career

He has had a distinguished career in the field of cognitive neuroscience. In 1993, he founded the Cognitive Neuroscience Society, a professional organization dedicated to advancing the field. From 1988 to 2003, he served as the founding editor and editor-in-chief of the Journal of Cognitive Neuroscience.
Gazzaniga's academic career began as an assistant professor of psychology at UCSB in 1967.
In 1969 he moved to New York University graduate school as an assistant professor, and in 1972 became a full professor. In 1973 he took a position as professor of psychology at the State University of New York at Stony Brook and later became a professor of social sciences in Medicine.
This led to Cornell University Medical College, where he was appointed Director of the Division of Cognitive Neuroscience and a Professor of Neurology and Psychology from 1977 to 1988.
In 2009, he delivered the Gifford Lectures on Mental Life at the University of Edinburgh. In 2019, Trinity College Dublin awarded him with an honorary doctorate.
Gazzaniga's publication career includes books for a general audience such as The Social Brain, Mind Matters, Nature's Mind, The Ethical Brain and Who's in Charge?, which is based on the Gifford lectures he presented at the University of Edinburgh in 2009. He is also the editor of The Cognitive Neurosciences book series published by the MIT Press, which features the work of nearly 200 scientists and is a sourcebook for the field. His latest book is entitled The Consciousness Instinct: Unraveling the Mystery of How the Brain Makes Mind, published by Farrar, Straus and Giroux in 2018.

## Research
### Early research

Gazzaniga is known for his pioneering work in the field of cognitive neuroscience. His research with split-brain patients has been instrumental in understanding the distinct roles of the left and right hemispheres of the brain. In split-brain patients the corpus callosum, the giant nerve bundle which connects the right and left hemispheres, had been severed to limit the transmission of nerve impulses across the brain in the hopes of decreasing previously intractable seizures. The original series of split-brain patients, whose callosotomies had been done in the 1930s in Rochester, New York had been previously tested, and no evidence was found that there was any disruption of the interhemispheric transfer of information after callosotomy. Later, however, Sperry and his graduate student Ron Myers found that severing the corpus callosum in monkeys did block the transfer of information.
As a first-year graduate student at Caltech, Gazzaniga, convinced by the monkey research that transfer of information would be interrupted, began to test the first California split-brain patient with a testing procedure that had not been done on the previous series of split-brain patients. He designed an apparatus that flashed a letter, number or symbol onto a screen to either the right or left visual field while the patient focused on a central point.

### Patient W.J.

Patient W.J. was a World War II paratrooper, the first of a series of patients that underwent a callosotomy on the West Coast.
He had developed grand mal seizures after a German soldier knocked him out with a rifle butt after a parachute jump behind enemy lines. Before surgery, Gazzaniga tested W.J.’s brain functions. This included presenting stimuli to the left and right visual fields and identifying objects placed in his hands that were out of view. After he had the surgery, the test results were different. When a picture of an object was flashed to his right visual field, he was asked if he saw anything: He quickly named the object. When a picture was flashed to his left visual field, he denied seeing anything. Then a circle was flashed on the screen. This experiment opened the door to years of research by Gazzaniga and colleagues that has revealed that severing the callosum prevents the transfer of perceptual, sensory, motor, gnostic and other types of information between the left and right cerebral hemispheres. Extensive research has shown that many of the brains processes are lateralized, such as speech and language to the left hemisphere, along with analytical thinking and the capacity to interpret behavior and unconsciously driven emotional states, while visuospatial processing, facial recognition, attentional monitoring, and the ascribing of beliefs to others are right hemisphere processes.

### Patient P.S.

Patient P.S. was a teenage boy, the first split-brain patient studied from the east coast series who had a full callosotomy. He was also the first split-brain patient in that series who demonstrated extensive language comprehension in the right hemisphere.
His right hemisphere was able to label pictures of objects by spelling out the appropriate word with Scrabble tiles. Even though he was right-handed, he could roughly write words with his left hand, even though he could not speak them. All these findings led Gazzaniga and his graduate student Joe LeDoux to wonder if the right hemisphere would be able to answer subjective and personal questions, did it have its own identity? For example, they started out by saying, “Who” and then flashed the word ‘are you’ to his left visual field and thus his right hemisphere. He spelled out PAUL with his left hand using the tiles.

## Selected publications

* Gazzaniga, Michael S. (1970). The Bisected Brain. New York: Appleton-Century-Crofts. ISBN 978-0-390-35278-1.
* Gazzaniga, Michael S.; LeDoux, Joseph E. (1978). The Integrated Mind. New York: Plenum Pr. ISBN 978-0-306-31085-0.
* Gazzaniga, Michael S. (1987). Social Brain: Discovering the Networks of the Mind. Basic Books. ISBN 978-0-465-07850-9.
* Gazzaniga, Michael S. (1988). Mind Matters: How Mind and Brain Interact to Create our Conscious Lives. Boston: Houghton Mifflin. ISBN 978-0-395-50095-8.
* Gazzaniga, Michael S. (1992). Nature's Mind: The Biological Roots of Thinking, Emotions, Sexuality, Language and Intelligence. New York: BasicBooks. ISBN 978-0-465-04863-2.
* Gazzaniga, Michael S. (2000). The Mind's Past. Berkeley, Calif: University of California Press. ISBN 978-0-520-22486-5.
* Gazzaniga, Michael S. (2005). The Ethical Brain. New York [u.a.]: Dana Press. ISBN 978-1-932594-01-0.
* Senior, Carl; Russell, Tamara; Gazzaniga, Michael S. (2006). Methods in Mind (1st ed.). Cambridge, MA: The MIT Press. ISBN 978-0-262-19541-6.
* Gazzaniga, Michael S.; Ivry, Richard B.; Mangun, George R. (2009). Cognitive Neuroscience: The Biology of the Mind (3rd ed.). New York: W.W. Norton. ISBN 978-0-393-92795-5.
* Gazzaniga, Michael S. (2009). Human: The Science Behind What Makes Us Unique (1st ed.). New York: Harper Perennial. ISBN 978-0-06-089289-0.
* Gazzaniga, Michael S. (2011). Who's in Charge?: Free Will and the Science of the Brain (1st ed.). New York, NY: Ecco. ISBN 978-0-06-190610-7.
* Gazzaniga, Michael S. (2015). Tales from Both Sides of the Brain: A Life in Neuroscience (1st ed.). New York, NY: Ecco. ISBN 978-0062228802.
* Gazzaniga, Michael S. (2018). The Consciousness Instinct: Unraveling the Mystery of How the Brain Makes the Mind (1st ed.). New York, NY: Farrar, Straus and Giroux. ISBN 978-0374715502.

## Awards

* Elected fellow of American Academy of Arts and Sciences in 1997.
* Elected National Academy of Medicine (formerly called Institute of Medicine) in 2005.
* The Distinguished Scientific Contribution Award from the American Psychological Association in 2008.
* Dartmouth College Honorary Doctorate in 2011.
* University of Aberdeen Honorary Doctorate in 2011.
* The William James Fellow of the Association for Psychological Science in 2015.