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Free Will: Is Your Brain the Boss of You? [Video]

Philosophers have debated for years whether we deliberately make each of the many decisions we make every day, or if our brain does it for us, on autopilot.

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


Philosophers have debated for years whether we deliberately make each of the many decisions we make every day, or if our brain does it for us, on autopilot. Neuroscientists have shown, for example, that neurons in the brain initiate our response to various stimuli milliseconds before we’re even aware that we’re taking such an action.

This heady debate has hit a very practical road in the past decade: whether individuals who commit crimes are actually responsible for them. Lawyers have argued in court that if the brain determines the mind, then defendants may not be responsible for their transgressions.

Michael Gazzaniga, director of the SAGE Center for the Study of Mind at the University of California, Santa Barbara, is at the forefront of the research into free will, and its implications in courtroom trials and in the expectations of different societies. His thoughts and proclamations are captured in an engaging video called Free Will, created by Joseph LeDoux, a well-known expert on the emotional brain at New York University. The video is the second in a series he is putting together with director Alexis Gambis called My Mind’s Eye. (The first episode featured Ned Block on the mind-body problem.) They have given Scientific American the chance to post these videos first, on our site.


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How Free Is Your Will? An interview with Michael Gazzaniga from Imaginal Disc on Vimeo.

The conversation between LeDoux and Gazzaniga (who is also an editorial adviser to Scientific American) runs about 12 minutes, and Gambis has inserted some compelling imagery, including clips of creepy old movies in which scientists probe the brains of live people. The film then morphs into a four-minute music video of the song “How Free Is Your Will?,” performed by LeDoux’s band, the Amygdaloids. A few highlights of the interview, offered freely, by me:

2:55 Split-brain patients. Gazzaniga explains what has happened to these people, and what they can teach us about how we make decisions.

6:50 Personal responsibility. This is the crux of the argument about whether responsibility for our actions lies in the neuronal structures of the brain or in our conscious minds, and whether biological mechanisms or society’s norms are most important in defining acceptable behavior. “There’s no reason to not hold people accountable for their actions,” Gazzaniga maintains. He then discusses how society can more intelligently decide on what to do with people who violate its rules.

9:05 Criminal trials. Gazzaniga discusses problems in referring to brain scans in courtroom trials and in sentencing people who are convicted, and considers the effectiveness of capital punishment, given what we know about free will.

12:00 Music video of “How Free Is Your Will?”

Further reading, suggested by Michael Gazzaniga:

For the Law, Neuroscience Changes Nothing and Everything. Joshua Greene and Jonathan Cohen in Philosophical Transactions of the Royal Society B, 359, 1775-1785; 2004.

The Law and Neuroscience, Michael S. Gazzaniga in Neuron, 60:412-415; 2009.

Who’s in Charge? Free Will and the Science of the Brain. Michael S. Gazzaniga. Ecco, Harper Collins, New York; 2011.

Neuroscience in the Courtroom, Michael S. Gazzaniga in Scientific American, April 2011.

A Primer on Criminal Law and Neuroscience: A Contribution of the Law and Neuroscience Project. Oxford Series in Neuroscience, Law, and Philosophy; eds. Stephen J. Morse and Adina L. Roskies; 2013.

Image from this video courtesy of Imaginal Disc

Mark Fischetti has been a senior editor at Scientific American for 17 years and has covered sustainability issues, including climate, weather, environment, energy, food, water, biodiversity, population, and more. He assigns and edits feature articles, commentaries and news by journalists and scientists and also writes in those formats. He edits History, the magazine's department looking at science advances throughout time. He was founding managing editor of two spinoff magazines: Scientific American Mind and Scientific American Earth 3.0. His 2001 freelance article for the magazine, "Drowning New Orleans," predicted the widespread disaster that a storm like Hurricane Katrina would impose on the city. His video What Happens to Your Body after You Die?, has more than 12 million views on YouTube. Fischetti has written freelance articles for the New York Times, Sports Illustrated, Smithsonian, Technology Review, Fast Company, and many others. He co-authored the book Weaving the Web with Tim Berners-Lee, inventor of the World Wide Web, which tells the real story of how the Web was created. He also co-authored The New Killer Diseases with microbiologist Elinor Levy. Fischetti is a former managing editor of IEEE Spectrum Magazine and of Family Business Magazine. He has a physics degree and has twice served as the Attaway Fellow in Civic Culture at Centenary College of Louisiana, which awarded him an honorary doctorate. In 2021 he received the American Geophysical Union's Robert C. Cowen Award for Sustained Achievement in Science Journalism, which celebrates a career of outstanding reporting on the Earth and space sciences. He has appeared on NBC's Meet the Press, CNN, the History Channel, NPR News and many news radio stations. Follow Fischetti on X (formerly Twitter) @markfischetti

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