What is depression? Why are brains able to slip into it? Is depression detectable in animals? Do animals have options beyond fight or flight? And what does any of this have to do with measuring depression medications in city water supplies, reward pathways in the brain, the prevalence of tuberculosis, and zapping the head with magnetic stimulation? Join today's episode with David Eagleman and his guest -- psychiatrist Jonathan Downar -- for a deep dive into the brain science behind depression and what new solutions are on the horizon.

Do our visual systems see in frames like a movie camera or instead analyze the world continuously? Why do you see multiple hands when you clap under yellow street lamps? How did Hollywood launch from the question of whether all four legs of a galloping horse come off the ground at once? And what is the very surprising thing that happens if you stare at your ceiling fan for a long time while it turns? This week’s episode is about visual perception -- and a series of eye-opening revelations about how the brain takes in information from the world.

Can a person be declared legally dead even though he is very much alive? In December of 2010, why did a number of families choose to pull their loved ones off life support just before the new year? How do doctors decide when you've died, and how is it different from how lawyers decide? How is death a process rather than an event? What does any of this have to do with getting buried alive, your family's religious beliefs, or whether a head stays alive after the guillotine? Join Eagleman and guest Jacob Appel, an emergency room psychiatrist and head of ethics, for an episode about the science and the questions about death -- including who's domain it is to call it, and where this is all heading.

Who is the most disappointed medalist at the Olympics? How do brains simulate what might have been? How can you get your kid to wear a jacket in the cold? What if you had to face more successful versions of yourself? And what does any of this have to do with why menus should be shorter, why empires divide, and why you should always put yourself in the shoes of future people? Join Eagleman to learn the capstone secrets of mental time travel, and what these have to do with the emotions of regret and relief.

Why are people who can't remember their past also unable to picture their future? Why do we get so anxious about the world changing around us? What should you advise the president if we find ourselves at war with extraterrestrials? And what does this have to do with Wayne Gretzky, or the Greek goddess of memory, or hitting a bottle to get ketchup onto your French fries? Join this week's episode to find out about one of the most important things brains do: simulations of possible futures.

How do billions of neurons store your home address, your ability to ride a bike, and the history of your life? How does memory work in the brain, and how is it different from the way a computer stores information? And what does any of this have to do with the Happy Birthday song, squirrels hiding acorns, bards memorizing epics, or people who cannot forget any of the events of their life? Join Eagleman to learn how and why your brain continually time travels to previous moments.

What role will AI play in the future of fake news and misinformation? What does this have to do with our brains’ internal models, with voice passwords, and with what Eagleman calls "the tall intelligence problem"? And why does he believe that these earliest days of AI are its golden age, and we are quickly heading for a balkanization? Join for today's episode about truth, misinformation, and artificial intelligence.

What is the future of misinformation on the internet? Is it possible that the invention of the internet has improved access to truth? What does any of this have to do with the Oxford English Dictionary, Soviet agriculture, liberation technology, Kenyan elections, Barbra Streisand's house, and Twitter revolutions? Join Eagleman for a surprising foray into the thorny forest of truth in the age of the internet.

We all worry about fake news. But is misinformation and disinformation really new? Join Eagleman for a deep dive into the past, present, and future of truth. Why do cameras not tell us what we think they do? What should we not forget about pamphleteering? And what does this have to do with agriculture in the USSR, or book banning in America, or dog whistles, or apps that only tell facts? And why is it so hard to understand the viewpoints of millions of brains at once? This week's episode is the first of a three-parter -- and today we tackle truth in the media.

Why are our brains so wired for love? Could you fall head over heels for a bot? Might your romantic partner be more satisfied with a 5% better version of you? How does an AI bot plug right into your deep neural circuitry, and what are the pros and cons? And what will it mean when humans you love don’t have to die, but can live on in your phone forever? Join Eagleman for a deep dive into relationships, their AI future, and what it all means for our species.

Is it always harder to teach an old dog new tricks? Why is an older person slower to learn a new language but able to learn new faces easily? Why does Arnold Schwartzenegger have an accent but Mila Kunis doesn’t, even though neither spoke English as a child? Why is there a correlation between how tall a person is and how much salary they're likely to earn? What would it mean to say that you are born as many people but die as a single one? This week's episode dives into surprises about brain plasticity and why your flexibility changes throughout your lifetime. 

What does the insanity defense mean in a court of law? And is there such a thing as temporary insanity? Is the twinkie defense a real thing? Can someone use premenstrual syndrome as a defense? And what does the legal wrestling around insanity tell us about the differences between brains: yours and other people’s, or even yours one day and yours the next day? How does law comport with science, and how are they sometimes like two people with quite different ways of looking at the world? Join to find out what happened to Andrea Yates, how the legal system deals with mental illness, and so much more.

Eagleman answers listeners questions.

What is the insanity defense? Are some people’s brains so different that it makes sense to use a different legal category? How does a legal system decide where the dividing line is? How are science and law strange bedfellows? Join us for the first of two episodes about the insanity defense: where it comes from, where it's going, and why it is so difficult to decide where to draw our societal lines. 

f you look at a brain, how can you immediately tell if it belongs to a piano player or a violinist? How can a dog learn how to walk on its rear legs? And what does this have to do with expertise, or the good news about the brains of digital natives, or how governments respond to change just like brains do? While we all like to talk about brain plasticity, the truth is that most of what happens in your life makes no meaningful change to your brain. So what’s the difference between the stuff that sticks and the stuff that doesn’t?

What would it be like to have a much lower or higher IQ than you currently have -- for example, to be a squirrel or an advanced space alien? This week's episode is about intelligence. What is it and what is its history and future? Join Eagleman on a whistle-stop tour of several schools of thought about what intelligence might mean in the brain.

Why do they use a gun at the Olympics? And why can you get off the blocks after the bang but still be disqualified for jumping the gun? Few things are as bizarre as our time perception. From sprinters to basketball players, from Kubla Khan to Oppenheimer, from television broadcasting to hallucinations, Eagleman unmasks illusions of time that surround us. Why does the brain work so hard to pull off editing tricks? And what does this tell us about our perception of reality?

Does life end inevitably or instead only because we don’t understand biology well enough yet? Today’s episode is about understanding what happens when your molecular cycles grind to a halt... and whether there's anything we can do to hit control-Z. Join Eagleman and his guest Dr. Zvonimir Vrselja to dive into the weird possibility of understanding cells well enough to reverse death.

Eagleman answers listeners questions.

Why can you hear some sounds two different ways, depending on which word you’re looking at? Why do electrical outlets sometimes look like a face? How can you have rich visual experience with your eyes closed? Are some crosswalk buttons fake? Why are some pictures interpretable only once you’ve been told what to look for? And although brains are often celebrated for their parallel processing, what should they really be celebrated for? Tune in to learn what happens when the raw facts of the world collide with your expectations.

Can we explain our rich experience of life only by studying the molecules that compose us? How is the color of your passport related to your chances of presenting with schizophrenia? Males are more predisposed to commit crime, so why don’t all males commit crime? And what does any of this have to do with traffic jams, why Seinfeld is funny, and how we’re ever going to come to know ourselves from studying biology? Join Eagleman to talk about levels of understanding, what a meaningful explanation would look like, and the possibility that we are not near the conclusion of science's journey, but instead near the beginning.

Did Joan of Arc turn the tide of the 100 Years War as the result of a brain disorder? Would you appreciate Taylor Swift if you only had an internal camera to watch her vocal chords? What do almost all drugs of abuse have in common? How can the tiny molecules of rabies virus control your behavior? Join Eagleman on a two-part deep dive into the fundamental question of how biological insights can shed light on the ancient question of who we are.

Are there really dozens of words for snow in northern cultures? What did the movie Arrival have to do with language and cognition? Why are Russians better than Americans at distinguishing certain shades of blue? And what does any of this have to do with space, time, gender, and how your language influences your thought? Join Eagleman and his guest, cognitive scientist Lera Boroditsky, as they take a deep dive into the intersection of words and understanding.

Can your thoughts be read with neurotechnology? When is measuring the brain like reading the mind? How close or far are we from being able to know if you're thinking about some particular thing you did or intend to do? What's hype and what's real? Join Eagleman for a deep dive into mind reading: what it means, where we are now, and whether your thoughts could ever be readable with new technologies.

We all know people who hate the word "moist". But why are they fine with synonyms such as "damp" or "wet"? What’s going on in their brains, and what does this have to do with synesthesia, autism, shapes, slacks, and sound probabilities? Join this week's episode as Eagleman leads us into the new and wild world of word aversion.

Why are we humans so easily deceived? What are the tricks of the trade, and how can we train ourselves to be more aware of them? What does all this have to do with Theranos, forged letters, and the shell game? Although you presumably wouldn't cheat a stranger out of all her money, there are people who would -- so how can we beef up our immunity against deception? Join Eagleman with guests Christopher Chabris and Dan Simons to discuss their new book, Nobody's Fool.

Why do you still feel the waves after getting off a boat? Why does the wall seem to come at you faster after you step off the treadmill? Why do the rocks seem to move upward after you stare at a waterfall? Why did people in the 1980s think their book pages had some red color in them… but no one thought that before or after the 80s? And what does any of this have to do with drugs, heartbreak, yellow sunglasses, or Aristotle watching a horse stuck in a river? Join Eagleman to understand how the brain constantly readjusts its circuitry to best read the world, and what it means for our (sometimes strange) perceptions of what's out there.

If we meet extraterrestrials someday, how will we figure out what they're saying? We currently face this problem right here at home: we have 2 million species of animals on our planet... and we have no Google Translate for any of them. We’re not having conversations with (or listening to podcasts by) anyone but ourselves. Join Eagleman and his guest Aza Raskin to see the glimmer of a pathway that might get us to animal translation, and relatively soon. 

Why do briefly glimpsed people appear to be more attractive? Why did portrait photographers put Vaseline on their lenses, and what does that have to do with Instagram filters? Why are thirsty people more likely to perceive something as transparent? And what does any of that have to do with mating, optimal decision making, puberty, frogs, and movie stars? In this episode, Eagleman gets us to view the familiar as strange as we examine beauty, instincts, and what drives us.

Would you torture someone if you were commanded by an authority figure? To what degree are your decisions contextual, and what does this have to do with matching the length of a line, the Iroquois Native Americans, the banality of evil, soldiers posing with dead bodies of their enemies, propaganda, giving shocks to a stranger, or how we should educate our children? Join Eagleman for part 2 of the exploration into brains, dehumanization, and what we can do to improve our possible future.

Why do we so naturally form ingroups and outgroups? And what does that have to do with evolution, monkeys, Greeks, psychopaths, Syndrome E, and propaganda posters? Join Eagleman to learn why our brains are so wired for tribalism, what the consequences are for the world, and how a bit of knowledge goes a long way to making us more immune to propaganda. 

How good is your memory, really? Why do we feel so certain about our memory, even while it is so suspect? Can something told to you after an event change your memory of the event? Why is it so hard to reconstruct a face? Is there a relationship between confidence and accuracy? How is your ability to remember a scene changed if there's a gun pointed at you? Join Eagleman to find out why eyewitness testimony is the most questionable technology we allow in courts.

How would we know if we were living in a simulation? What if you were a butterfly having a dream it was a human? What does any of this have to do with John Lennon, or Renee Descartes, or freezing yourself in a vat of liquid nitrogen? How will we eventually solve the problem that human bodies can’t do space travel? Join Eagleman for a wild ride into the strange possibility of making brains immortal.

How do your billions of tiny brain cells build consciousness as they chatter away with electrical spikes and chemical signals? And why is your laptop, with its sophisticated algorithms and billions of parts, presumably not conscious? Could other large systems like a city become conscious? And what does this have to do with ant hills, blue birds, or your memory of your first kiss? Join Eagleman on a journey into one of the central mysteries of neuroscience: why we have awareness.

Why is there so much polarization, and what does this have to do with neuroscience? Why do people on all sides of the political spectrum feel that if they could shout loudly enough in all caps on Twitter, everyone would come to see they’re right? And what does any of this have to do with literature, genetics, nobleman Lord Gordon, bumperstickers, visualization, or the Iroquois Native Americans? Join as Eagleman draws from distant fields to show why we always feel so certain we know the truth.

When does neuroscience overlap with the legal system? Do we have free will or don't we? Did changes in Charles Whitman's brain have something to do with him becoming a mass shooter? Why was the heir to the Gucci fashion fortune killed by his wife? Join Eagleman on a wild journey to understand what happens when the study of the brain and the law end up in the same courtroom.

Who is doing the choosing when you make a choice? Is there someone in your head but it’s not you? What is a chicken-sexer, and what do they have to do with British plane spotters during WWII? Do we have free will or don’t we? Dive in to discover the ways in which you typically operate with no conscious access to your behaviors.

How far in the past do you live? Why are live television shows not actually live? What does any of this have to do with nuclear bombs, car accidents, plane crashes, volcanos, or the last episode of the Sopranos? Join Eagleman in a mind-bending dive into the neuroscience of time and what it could mean for your last moment.

Can a blind person come to see through her tongue? What would it be like to smell with the nose of a dog? How can we perceive streams of information that are normally invisible to us? And what does any of this have to do with pilots or Westworld or tinnitus or friendly fire or a wristband with vibratory motors? We don't detect most of the action going on in the world around us... and today we'll explore how technology might change that.

Why are some of the best musicians blind? Can blind people learn how to echolocate, like a bat? What do your nightly dreams have to do with the rotation of the planet? Once we find alien life on other planets, should we expect that aliens have dreams at night? Find out why dreaming might be the strange lovechild of brain plasticity.

What do charlatans have to understand about human perception? Why are you so bad at recognizing a real penny among fakes? What did Eagleman have to do with the redesign of the Euro, and why did he campaign to the European Central Bank that all their bills should be blank with a single hologram in the middle? In this episode, explore the crossroads of perception and deception. Brief appearance from special guest Adam Savage. 

We all have goals, and we all face temptations that get in the way. So what's happening in the brain when we act in a manner that isn't in accordance with who we want to be? Computers don’t have these problems, but being human can be tough. In the previous two episodes we exposed the rivaling networks battling it out under the surface. Today we’re going to talk about the gap between what you intend to do and what you actually do when temptation is there. 

What’s happening when you stand in the supermarket aisle and stare at the shelf full of options? It may not look like there’s much going on from the outside, but inside there’s a war of networks raging. How is your brain's decision-making influenced by price, emotions, and your group of friends? How would you choose between a nice candle and a chocolate bar in the shape of a computer keyboard? And what does any of this have to do with Starbucks or Tiger Woods or Burger King? 

Modern AI is blowing everyone’s mind. But is it intelligent like humans, or is it just playing impressive statistical games? Could AI reach or exceed our level of intelligence, and how would we know when it gets there? Traditional tests for intelligence (Turing test, Lovelace test, etc) have long been surpassed, so Eagleman proposes a new kind of test. 

Will writers, artists, and musicians find themselves unemployed by AI? What are the new capabilities we’re seeing and what does it all mean for human creativity? And what does this have to do with diamonds, Westworld, effort, Frankenstein, photography, Beethoven, and the Stark family in Game of Thrones?

Would you kill one person to save the lives of five others? Why do you find yourself on the horns of a dilemma when someone offers you a chocolate cake? How can you believe different things at once? Find out what's running under the hood in this first episode of a three-parter about our decision making -- and how a little knowledge of neuroscience can allow us to make better decisions.

Do you see blue the same way I do on the inside? Why do some people think the northern lights make noise? Why do you think the low note on the piano is larger, and the high note brighter? Join Eagleman on a wild ride into the world of synesthesia, a topic his neuroscience laboratory has pioneered for years. 

What is intelligence? Why don’t gophers write novels? Why didn't crows invent the internet? And what does any of this have to do with brain algorithms, finding aliens on earth, and why World War 5 could involve species besides Homo sapiens?

How is it possible for a dog to become a champion surfer? Why does the world’s best archer have no arms? Why might someone come to believe that her leg doesn’t belong to her? How can we build robots that simply figure themselves out? In this episode, Eagleman unmasks mysteries about the brain's shocking flexibility -- revealing how it comes to drive whatever body it finds itself in, how it determines what the "self" is, and what this tells us about our future as humans.

When he was a child, Eagleman fell off a roof and time seemed to run in slow motion. When he became a neuroscientist, he grew curious about the experience and collected hundreds of similar stories from others. But is it true that your brain can actually see in slow motion, like Neo in the Matrix? And how would you test that? Hear how he dropped volunteers from a tower to put the science to the test, and what the answer reveals about our perception, memory, and experience of the world.

Neuroscientist and author David Eagleman discusses how our brain interprets the world and what that means for us. Through storytelling, research, interviews, and experiments, David Eagleman tackles wild questions that illuminate new facets of our lives and our realities.