Science & Tools of Learning & Memory | Dr. David Eagleman

If you’ve mastered crossword puzzles, switch to something you’re bad at. Constantly chasing new, hard challenges is the lever for keeping the brain changing.

Welcome to the Huberman Lab Podcast, where we explore science and tools for everyday life. I’m Andrew Huberman, and today I’m joined by neuroscientist and master communicator Dr. David Eagleman to dive into plasticity, learning, memory, time, stress, dreams, polarization, and how understanding mechanisms lets us rewire better.

Let’s start with neuroplasticity. How do you define it, and how should we apply it?

Humans arrive with a half-built brain that the world finishes wiring. Cortex is the key; it runs the same algorithm everywhere and becomes vision, hearing, or touch based on the inputs you plug into it, which gives us vast room to think, delay action, and simulate futures.

So the cortex is flexible. In blindness, does visual real estate get reassigned, and what does that say about specialization versus sampling broadly as kids?

Nothing lies fallow. In the congenitally blind, “visual” cortex repurposes for hearing, touch, memory, and performance improves. The more cortical real estate a task gets, the better you get, which can help explain some savant abilities but also trade-offs. Deep practice burns skills into hardware, yet breadth can scaffold learning across domains; bilingual kids may have smaller vocab in each tongue early, but the second language is still worth it.

Rewards gate plasticity. When curiosity is high, the chemical cocktail for change is present, which is why on-demand learning via the internet can make knowledge stick far better than one-size-fits-all lectures.

I used to bike to bookstores for answers. Instant access probably would’ve let me build more. I now keep social media on a separate phone and even lock it away for hours to protect attention. Can we actually expand our plasticity window or heighten it with specific activities?

Seek novelty. Live at the edge of frustrating but achievable. Social engagement, new skills, and modern tools all help, and staying mentally engaged as we age builds cognitive reserve, as seen in nuns who showed Alzheimer’s pathology yet functioned well because daily life kept rewiring detours around damage.

The agitation of learning feels like catecholamines doing their thing. Why do so many different neuromodulators seem able to open plasticity, and how should we think about that in light of psychedelics and drugs that boost them?

These chemicals work in combinations, not silos. Acetylcholine flags surprise broadly in infancy and in tight spots in adulthood. Tweaking systems can have side effects, like dopamine meds for Parkinson’s shifting risk-taking toward gambling. Primary sensory areas lock down early, while higher areas that recognize people or new brands stay plastic lifelong.

So the aim isn’t raw plasticity. It’s directed plasticity, and overdoing it can destabilize identity.

Exactly. You wouldn’t want infant-level malleability. Who we are is our memories and skills, continuously updated but not wiped.

We all fixate on our future selves. How should we set horizons that serve who we want to become without getting trapped in fantasies or hyper-present stoicism?

Our superpower is simulating futures with prefrontal cortex while managing inner conflicts, like the part that wants the cupcake and the part that doesn’t. Ulysses contracts help: bind your future self when you’re clear-headed so you can’t act badly when impulses surge.

Lock the phone away. Freeze cash if you overspend. Add social pressure with a gym buddy or a boot camp that literally shows up. Put money on the line, even to causes you abhor, to make breaking a vow unthinkable.

We still need contracts for building, not just avoiding. How do we make the good behaviors stick?

We’re bad at resolutions, so design for your lazy future self: reduce friction, pre-stage the environment, and create stakes. Put your shoes by the door, commit funds to goals, and let systems carry you when motivation dips.

Some people overthink; others just act. Is that inner voice difference real, and how does imagery ability fit in?

It’s all spectra. Inner narration ranges from constant to quiet. Imagery spans aphantasia to hyperphantasia. Many great Pixar creatives are aphantasic, which may force deeper dialogue with the page and sharpen drawing through observation and iteration.

Do silos and specialization actually drive human progress, and is it okay that we close doors we’ll never reopen?

Predispositions and circumstances define a cone of possible futures. Parents should open many doors, then let kids choose. The brain starts hyperconnected and then prunes based on experience; every chosen path strengthens some circuits and lets others fade.

I practice shifting attention across body, environment, and vast space to flex time perception. Does attention shape time, and can we train this?

I love that. The brain uses different systems for subsecond timing versus long arcs, and our sense of deep time develops with life experience. Zooming in and out, even in literature, expands cognitive range, and your exercise likely builds that flexibility.

Why am I always late, and are we actually good at perceiving time?

Commit to arriving five minutes early and wait in the car. We’re poor timekeepers, and much of time is memory. In my freefall study, people didn’t perceive more frames during danger, but they later recalled the fall as longer because the amygdala wrote extra-dense memories.

Novelty stretches felt time because you lay down more distinct memories. To live a life that feels fuller, pay real attention and keep switching it up: brush with your other hand, take a new route home, rearrange your office.

Maybe contracts buy us the freedom to be present. There’s beauty and tragedy at every scale; we just don’t want to get trapped at one level of zoom.

Agreed. Choose what truly deserves attention, like a phone-free dinner with friends. Perseveration on one narrow loop can be tragic, as in superstitious behaviors that hijack prediction.

On addiction, I see scrolling that leaves people drained. Is that plasticity at work, and does it parallel heartbreak?

Addiction is plasticity: the brain upregulates in expectation of a substance or experience, so withdrawal hurts when it’s gone. Heartbreak feels similar because your brain had modeled life with that person and must painfully rewire when they’re absent.

Used well, YouTube and AI are amazing teachers, and I love learning during workouts. The right algorithms can open doors you’d never find.

That’s why I’m bullish on kids learning now. I even fix things at home by watching videos or asking AI to analyze photos, and it’s surprisingly helpful. For the record, I sold Neosensory six months ago.

Neosensory is such a wild idea, turning sound into touch. Can anyone benefit from that kind of sensory cross‑wiring, even if they are not missing a sense?

Yes. We can feed information into the brain through unusual channels and the system will learn it by correlation. Our wristband converts sound into vibrotactile patterns, much like the cochlea converts vibration into spikes. This builds on a long lineage, from early forehead buzzers to Paul Bach‑y‑Rita’s back‑poking array, and now the BrainPort that sends camera images to the tongue; blind users can navigate and even report a sight‑like experience. After months with our wristband, a user did not feel a buzz and then infer a dog bark; he perceived the bark out in space. That is the brain doing what it always does—constructing the world from spikes inside the skull.

Ed Yong’s book on animal senses made me think it is less about which sense is best and more about reliance. I suspect many of us could learn echolocation if we needed it.

We can. Blind people have long used tongue clicks, canes, and echoes to map space, and sighted people can learn it with motivation. I call this the Mr. Potato Head view of the brain: evolution built one flexible engine and you can plug in different peripherals. Animals read infrared, electric fields, or magnetism; we can add channels too, like a vibrating compass belt that teaches north. Sensory substitution, enhancement, and addition all work because the brain is plug‑and‑play.

Let’s shift to dreams. Where do the vivid visuals come from, and do aphantasia or hyperphantasia change dream imagery?

I do not see a clear split in dream vividness across that imagery continuum. My broader view is that REM exists to defend the visual cortex overnight. Cross‑modal connections are poised to take over idle territory; blindfolded people show touch and sound creeping into visual cortex within about an hour. Because nights were truly dark over evolutionary time, vision went offline while hearing, touch, taste, and smell stayed active. So every ninety minutes a midbrain circuit fires through the thalamus into primary visual cortex to keep that real estate claimed. We experience the volley as a movie with emotion and story. The cross‑species pattern fits: more plastic species and human infants spend far more time in REM, and REM drops with age as plasticity wanes. People who are blind still dream, but their occipital cortex represents other senses, so their dreams are rich in touch and sound rather than images.

A magician told me about doing auditory‑only magic for blind audiences, which makes me want to try blindfolded perception training. Counselors sometimes do that for days and report real shifts.

Exactly. After extended blindfolding, their experience changes because the brain rapidly adapts.

On to science and the law. In high‑stress events, does the more stressed person form denser, more accurate memories than a calmer witness, or does stress cap accuracy?

Victims often show weapon focus, locking onto a gun or knife at the expense of faces. And even amygdala‑tagged memories drift. In a longitudinal study around September eleven, highly emotional memories changed over months and years as much as mundane ones. This is bad news for the courts. Each recall is a rewrite, and confidence can be inflated by suggestion. Good practice tries to curb that—separating witnesses, avoiding feedback, and educating juries—but we are still very swayed by a firm eyewitness. I demonstrate this in class with an actor and a planted detail; students converge on the false mole I mention, which shows how easily memory gets contaminated.

Are kids more prone to distortion? And what about the way photos might scaffold or replace real memories?

Children are easier to influence. Elizabeth Loftus has shown how people can adopt entirely fictitious childhood episodes like getting lost in a mall. On the flip side, constant exposure to personal photos may strengthen recall through repetition. Taking pictures can dilute presence at a concert, but seeing those images later might extend the memory. The immediate experience shrinks while the long tail grows.

We are living in strong echo chambers. I wonder if empathy shifts not only when others are harmed but also when they benefit. Many people feel stung when someone they dislike gets a win, even if nothing was taken from them.

Our brains privilege in‑groups at a very fast, low level. In the scanner, watching a labeled hand get pricked activates the pain matrix more for in‑group than out‑group, and even arbitrary teams induce that bias. Sometimes the reward system lights up when an out‑group suffers, which is sobering. Fairness instincts run deep too; classic monkey studies show anger when a neighbor gets a sweeter reward. This all feeds polarization and can be weaponized. Propaganda works by dehumanizing, which turns down prefrontal circuits for social care; once the other is framed as vermin or a virus, terrible acts become thinkable. I am focused on inoculating people against that trick and on teaching the limits of our internal models. We can blunt bias with practices like blind auditions and by complexifying relationships. The Iroquois created cross‑cutting clans so alliances overlapped, reducing bloodshed. We reproduced a version of that by redefining allies across religious labels; empathy followed the new lines. I have even patented a social media approach that first surfaces shared interests so people build rapport before touching hot topics.

I once thought intermarriage across identities would dissolve polarization, but history shows fault lines can be redrawn. Before we wrap, you are juggling so much. What are you building now?

My podcast Inner Cosmos lets me explore big ideas, mostly solo with occasional guests. I have two books underway, The Ulysses Contract and Empire of the Invisible. And I am producing a documentary with Craig Ferguson to test whether AI can be funny. He will tour with a robot so we can ask serious questions about AI through comedy rather than doom.

David, this was a blast. You teach, you experiment, and you tell stories with real rigor. Please come back.

Thanks, Andrew. I had a great time.

Thanks for joining me for today’s conversation with David Eagleman. You can find links to his work and books in the show note captions. If you are learning from and enjoying this podcast, please subscribe on YouTube, follow on Spotify and Apple, and consider leaving a five‑star review and a comment. Supporting the sponsors mentioned at the beginning and throughout the episode is the best way to support the show. If you have questions or topic requests, put them in the YouTube comments; I do read them. I also have my first book coming out, Protocols, an operating manual for the human body. It is available for pre‑order at protocolsbook.com. Follow Huberman Lab on Instagram, X, Threads, Facebook, and LinkedIn for science and tools that go beyond the podcast. And sign up for our zero‑cost Neural Network newsletter at HubermanLab.com for summaries and one‑ to three‑page protocol PDFs on sleep, dopamine, cold exposure, and fitness. Thank you again for listening, and thank you for your interest in science.