Is the human brain an elaborate organic computer? Since the time of the earliest electronic computers, some have imagined that with sufficiently robust memory, processing speed, and programming, a functioning human brain can be replicated in silicon. Others disagree, arguing that central to the workings of the brain are inherently non-computational processes. Do we differ from complex computer algorithms? Are there essential features of the physical make-up and workings of a brain that will prevent us from creating a machine that thinks? And if we should succeed in constructing a computer that claims to be sentient, how would we know if it really is?
This program is part of the Big Ideas Series.
Since joining ABC News in 2004, Bill Weir has anchored several launches and landings of the Space Shuttle, was the first American to broadcast live from Tibet, and led off 2007’s Earth Day special with an unprecedented underwater live report from the Great Barrier Reef. His in-depth reports on the economic rise of China and India were signature features on Good Morning America, and he led the network’s coverage of Iraq, Where Things Stand at the height of the American troop surge. Domestically, Weir’s reporting often focuses on innovative solutions to America’s biggest problems, from border security and new energy to health care and education reform to the cause and effect of 2009’s recession.
Weir is the co-anchor of Nightline and the former weekend edition of Good Morning America. His reporting is seen on World News with Diane Sawyer, Nightline, and 20/20. In June 2007, he was named host of the ABC News magazine iCaught, and as a writer and host, he produced special hours for the network on topics ranging from religion, to brain science, to the rise and fall of General Motors.
R. Douglas Fields is a developmental neurobiologist and author of The Other Brain, a popular book about the discovery of brain cells (called glia) that communicate without using electricity. He is an authority on neuron-glia interactions, brain development, and the cellular mechanisms of memory. Fields serves on the editorial board of several neuroscience journals and also enjoys writing about science for the general public in Scientific American, Huffington Post, Psychology Today, Outside, Odyssey, BrainFacts.org, and others. He received advanced degrees from UC Berkeley, San Jose State University, and the University of California, San Diego. He held postdoctoral fellowships at Stanford, Yale, and the National Institutes of Health. He is currently chief of the section on nervous system development and plasticity at the National Institute of Child Health and Human Development at the NIH. In addition to science, Fields enjoys building guitars, rock-climbing, and scuba diving.
Kristen Harris is one of the world’s leading neuroscientists investigating synapse structure and function. She has been a professor of neuroscience at Harvard, Boston University, Georgia Health Sciences University, and since 2006 in the Center for Learning and Memory at the University of Texas at Austin. She is the author of numerous publications and recipient of the prestigious Sloan Fellowship and Javits Neuroscience Investigator Awards, and she serves as a reviewer for the National Institutes of Health. Her research uses 3D reconstructions from electron microscopy to decode the cell biology of learning and memory. Recent findings show that mature neurons sustain a maximum synaptic capacity, exactly balancing the strengthening of some synapses by eliminating weak neighbors during long-term potentiation, a cellular mechanism of learning. These novel findings provide the basis for new understanding of structural and molecular mechanisms of synapse growth and elimination in the mature brain, a crucial step in developing treatments to mend the mind.
Murray Shanahan is a professor of cognitive robotics at Imperial College London. In the 1980s, he studied computer science as an undergraduate at Imperial College, and then obtained his Ph.D. from Cambridge University (King’s College). Since then he has carried out work in artificial intelligence, robotics, and cognitive science, and has numerous peer-reviewed publications in these areas. For the past decade or so, he has turned his attention to the brain, and the relationship between cognition and consciousness. His book Embodiment and the Inner Life, was published in 2010.
Gregory Wheeler, born in 1968, is an American logician, philosopher, and computer scientist, who specializes in formal epistemology. Much of his work has focused on imprecise probability. He is a visiting associate professor of philosophy at Carnegie Mellon University, and has been a research scientist at the Max Planck Institute for Human Development in Berlin, a senior research scientist in artificial intelligence and member of the board of directors at the Center for Artificial Intelligence Research at the New University of Lisbon. He is a member of the progic steering committee, the editorial board of Synthese, and is the editor-in-chief of Minds and Machines. He obtained a Ph.D. in philosophy and computer science from the University of Rochester under Henry Kyburg.