The Brain with Dr. David Eagleman

A contemplative journey exploring how the brain weaves a rich multi-sensory experience of reality from within the darkness of the skull.

Episode two, "What Makes Me?", explores the question of how the brain gives rise to our thoughts, emotions, our memories and personality. Philosophers and great thinkers have for millennia pondered the question of how physical stuff can give rise to mental processes. Last century, the new field of neuroscience joined the discussion, and Dr. David Eagleman explains that to a neuroscientist, the answers to such questions lie in a deep understanding of the brain. The process of becoming who you are begins at birth. The human brain starts life remarkably unfinished, which accounts for the fact that babies are completely dependent on adults, compared to many mammals that can walk, fly and swim soon after they are born. A baby has almost as many neurons or nerve cells as an adult brain but instead of being connected to each other, the great majority are unconnected. Wiring up begins immediately, and rapidly, as the child's brain starts to adapt to whatever environment - culture, habitat, language - it's born into. Animals may be able to start life almost ready to go but they have none of the flexibility and adaptability of the human brain. The process of becoming a fully developed human takes a long time, and the brain doesn't stop forging new connections when we become adults. As we make new memories, learn new skills, and have life experiences the brain is constantly and dynamically rewiring itself. It never stops. Nor do we - the human brain is always changing, and therefore so are we. From cradle to grave, we are works in progress.

A scientific look into the control aspect of the brain/mind. Does free will exist? Are we entirely the products of our genes and our environment. Does our unconscious mind make most of our decisions? What does our conscious awareness do, what is it for? Take a deeper look at these questions and others, in a quest to better understand the human brain.

The human brain is the most complex object we've discovered in the universe, and every day much of its neural circuitry is taken up with the tens of thousands of decisions we need to make. "How Do I Decide?" is a journey through the unseen world of decisions, and how they get made. We start with a simple one: choosing a flavour of frozen yoghurt, and learn that every decision we make is born of a "winner takes all" competition between rival neural networks. As David ponders the choice before him - mint verses lemon - inside his brain, two rival networks are fighting it out. As one begins to get the upper hand, it causes the other network to be less active, until a threshold is crossed, the decision is made: he goes for mint. Every decision we make is underpinned by this kind of neural conflict, and what's more, many of these important battles are won, and lost, without us being consciously aware of it. Professor Read Montague reveals that he can be 95% certain about which political party we will vote for based on our brain's response to disgusting imagery. The more disgusted a brain response is the more likely that person is to vote conservative. Finally, Dr. Eagleman takes a look at how we can take better control of the decisions we make, and uses an exciting new technique called fMRI neuro-feedback to retrain the brains of drug addicts who want to make better decisions, to say "no."

In "Why Do I Need You?" Dr. David Eagleman explores how the human brain relies on other brains to thrive and survive. This neural interdependence begins at birth. Dr. Eagleman invites a group of babies to a puppet show to showcase their ability to discern who is trustworthy, and who isn't. Brain scans reveal that when we see someone in pain, we feel it too. Circuits within the brain's pain matrix light up in both cases. And this is the basis of empathy. Our social brain draws us together into groups. In groups humans have accomplished great things - from football games to music festivals, from peopling the world to building great civilizations. But there's a darker side. For every "in group" there is always an "out group." Dr. Eagleman's lab has shown that belonging to an "in group" means that at an unconscious level our brains care less about members of the "out group." He journeys to modern day Bosnia to hear from an eyewitness about what happened in 1995 when genocide returned to Europe. What could have allowed for such horrific group on group violence? Dr. Eagleman believes that neuroscience offers important answers. Dr. Lasana Harris at Leiden University has discovered that there are certain circumstances under which the human brain stops perceiving others as human, and when we perceive others as less than human it's easier to ignore them, and it's easier to suspend the moral and social rules we normally live by.

In "Who Will We Be?" Dr. Eagleman journeys into the future, and asks what's next for the human brain, and for our species. Mother nature has evolved a brain that is able to rewire itself according to its environment, which means that as technological advances continue apace, our technology is on a crash course with our biology. Dr. Eagleman describes ways in which we'll be able to plug new sensory inputs into our brains, to perceive more of physical reality than we currently do. For instance, although we now see in the visible spectrum new technologies could allow us to see in ultra violet or infra-red. Or we could have a totally new sense like the vibratory sense that Dr. Eagleman is himself working on. In addition, modern day "brain-machine interfaces" will one day allow us to enhance our physical bodies. The biggest game changer as a species would be if we discovered a way to upload our brains into digital space. Dr. Eagleman explores what it would take to do so. We would need powerful computers, and a complete map of the brain's connections, as well as the activity that runs on top. But would this simulation be conscious? Neuroscientists may discover that what's important is not what the brain is made of but what it does, and if we can faithfully represent the computations it makes on another non-biological medium, then we may make the move from biological to digital species.