Michael Gazzaniga: "Who's in Charge: Free Will and the Science of the Brain"

Michael Gazzaniga: "Who's in Charge: Free Will and the Science of the Brain"

A neuroscientist on what recent brain research can teach us about our choices in life and to what extent we can be held accountable: Free will and the science of the brain

Recent research in neuroscience suggests that much of what we do is hard wired.It’s tempting to believe that further research will eventually demonstrate that physical properties of the brain fully control the human mind. But neuroscientist Michael Gazzaniga argues we already have enough data to conclude that human behavior is not fully predetermined. He claims that a sense of responsibility, for instance, derives not from within a single brain, but from social interaction. Please join us for a conversation with Michael Gazzaniga on the concept of free will and the science of the brain.


Michael Gazzaniga

director of the SAGE Center for the Study of the Mind at the University of California, Santa Barbara; president of the Cognitive Neuroscience Institute; and founding director of the MacArthur Foundation’s Law and Neuroscience Project.

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Program Highlights

Advances in neuroscience point to an ever more complex system, and a system that operates almost completely beneath our consciousness. But in a new book, neuroscientist Michael Gazzaniga argues that not all of our thoughts and actions stem from cell-to-cell events. He explains why he believes social interaction plays a critical role.

Some Major Misconceptions About the Brain

About 60 years ago, scientists thought that the brain was basically a blank slate, or, as Gazzaniga puts it, "a big piece of putty." Gazzaniga's mentor, Roger Sperry, showed that neurons grow in particular ways to get to specific parts of the brain - which demonstrated that the brain is already structured, rather than a blank slate. Developmental psychologists then began demonstrating that babies, at a very young age, have concepts of social interactions like reciprocity and retribution. "We come with a lot of complexities built in," Gazzaniga said.

Dividing the Hemispheres

Decades ago, doctors sometimes treated epilepsy by severing the connection between the right and left hemispheres of the brain. Observing such patients made it obvious that one hemisphere is not aware of what the other is doing. There's a special part of the left brain that scientists call "the interpreter," and it tries to make sense of all the behaviors and mood modulations that one experiences from moment to moment. "The reason we think we're free and acting of our own free will is this thing says, well, who else is doing this. I must be doing it," Gazzaniga said. "This thing is very strongly present in all of us, which is why we find it so hard and difficult to think that all of our actions are really being organized by a rather automatic brain process."

Are All Human Brains Basically The Same?

Though there are certain aspects of the brain that are common to many of us, like "the interpreter," and there may be a general plan that is the same, Gazzaniga said that there are many differences from one human brain to another. "The large layout is identical, but the individual wires are completely changed," he said. "People think, very confidently, that ultimately the differences between you and your personality and me and my personality will be discovered in knowledge of those minute connections."

A Life in Science "The Greatest Life There Is"

Gazzaniga started out as a young neuroscientist wanting to figure out how neurons get to their specific points. Roger Sperry and his team were just starting to study the phenomenon in humans, so Gazzaniga had the first-ever opportunity to focus on it in people. "There's nothing like
doing an experiment and showing a relationship...there are points where you make a discovery and you know something about nature that no one else knows for a few months, years, moments, whatever it is," Gazzaniga said.

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