When Your Eyes Can’t See, but Your Brain is Still Watching


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Images Courtesy of Getty Images

Narrator: Stephanie Sammann
Writer: Lorraine Boissoneault
Editor: Dylan Hennessy (
Illustrator: Jacek Ambrożewski
Illustrator/Animator: Kirtan Patel (
Animator: Mike Ridolfi (
Sound: Graham Haerther (
Thumbnail: Simon Buckmaster (
Producer: Brian McManus (


Date: June 24, 2023

47 thoughts on “When Your Eyes Can’t See, but Your Brain is Still Watching

  1. The whole human body along with brain and other organs/part is just insane, there is just no words to describe about them.

  2. About echolocation – it's interesting to think that for the majority or their existence, mamals were small, nocturnal, ground dwelling creatures (in contrast to most other vertibrates) that relied on senses besides vision. You can see that in how mammalian eyes often lack cones, and are often suited to low light environments.

    I wonder if there aren't other mamal species that echolocate to a degree that isn't obvious. Deer whistling comes to mind.

  3. For these times when we feel silly : we calculate things without even thinking.Our brain combined with two eyes, calculate the distance of the objects, instantly. There is no doubt at all, if this chair is closer (or further) to us than that lamp. Well, monkeys and most animals are able to do the same, but what I mean is : we underestimate our ability to calculate things, but we do it even unconsciously.

  4. I can design pairs of pearl eye then entangle with brain wave will see just like normal eye that is why no pilot can survive nor soldier can see what their weapon when war happen

  5. I've always wondered how it is possible for my eyelids to automatically close themselves when cycling at full speed and encountering a tiny fly head on. Somehow it closes just in time, bouncing the fly off and then a millisecond after it happened I receive the realization it just happened. So interesting that /something/ decides to bypass the default path and choose the quick reflex one instead.

  6. My father suffered an atypical stroke a few years ago. He was blind but could still react to things and even seem to see some detail from time to time, but couldn’t describe what he had seen or understand what he was going on. Was both fascinating and sad.

  7. This video made me think about Dare Devil and that maybe with training blind people could bring themselves to have similar sensory abilities that the character has. Obviously the crime fighting ninja abilities aren't gonna come with blindness though haha. I would love to know what blind people sense when they have their eyelids shut and when they have them open? Does anything feel different?

  8. So is this basically why we get that "Someone is watching me" feeling or when you get the sense you're not alone or when someone is behind you?

    Amount of times I notice people around me without actually looking at them

  9. I have a blind cat (no eyes.) She not only survives, but thrives and will try to fight other cats. She's significantly bigger than them (15+ lbs, not fat) and has some razor sharp claws. She listens better than any dog I've ever owned. Literally responds to commands like "come", "sit", and "where's your bed?"

    Amazing little kitty. The shelter I rescued her from named her Helen Keller lol.

  10. Hoooold the fort, the human brain being the most complex matter in the universe comes off sounding like anthropocentric arrogance. Wasn't it last week Earth was the center of the universe? Perhaps so far as we can hold in our hands, one could say. Wouldn't the solar mass UY Scuti be a much more complex piece of matter? Or a black hole?

  11. This video made me think of Eşref Armağan, a Turkish painter who was born blind but who understands colour and is capable of using it in his paintings (check out the painting he made for Volvo to see an example). I love that this is even possible and I love how baffling it is to me.
    There's also a research paper about Armağan, where two researchers monitored his brain activity while he painted. I highly recommend checking out the article, you can find it in the references on the English wikipedia page about Eşref Armağan.

  12. Errrr, the sound of thunder gets to you later than the vision due to the speed of sound, has nothing to do with your brain. Infact its the opposite. any reasons as to why they still use a gun to start a sprint race,,,, yeah the brain is faster to detect and react to it than vision.

  13. There is a mistake here 3:38 .,I am wiling to bet that it actually is more like around 1 % ! to be 10 % would mean you blink 60 times per second since one blink is around 100 ms! Otherwise Great vid ! I love your vids 🙂

  14. Back in the early '90s I had this same idea to design something to do echo location for blind people. But I didn't have the technical skills or equipment to pull it off. I am so glad to hear that it became a real thing.

    Re Brilliant, I wish the gov't could come up with a federal grant to make it free to everyone. It's far too valuable to be kept behind a pay only portal.

    Speaking of that alternate path in the visual system, I wonder if that accounts for highway hypnosis? I have always attributed highway hypnosis to attention, in that you only remember what your attention is on so if you are day dreaming while driving, your fresh memories are only aware of what you were thinking about, not what you were in fact looking at. But maybe there is more there. Maybe the memories and consciousness is only aware of what passes through the one main path even though there are other paths. Does the imagination appear as a portion of the brain distinct from the visual cortex?

  15. You can see perfectly in your dreams. You can induce light you see with your eye lids closed. Both would be impossible if the physical eye ball(s) was the only mechanism of vision.

  16. Dr jordan peterson was talking about this year's ago in an old lecture when he was explaining how we see things as their utility before we see them as objects, he said we don't see a cliff we see a falling off place lol, and how people who have damaged eyes can still detect things

  17. Funny thing, I do indoor bouldering and during the peak of covid, I'd see people's facial expressions in my memories instead of their masks. Brains be wild

  18. I'm walking talking proof the brain sees without seeing. Last week i was grinding on fresh welds, a tiny piece of slag flew up under my glasses and i blinked and got hit on eyelid. I didn't "see" it but mind and body reacted in time it took for piece of slag to fly off the 10k rpm grinder at waist level and reach my face.

  19. I've heard they have the technology now to interpret dreams into images. They've also used it to recreate images in real time as people are presented images. Apparently it's becoming pretty accurate. I wonder what might show up for blind people.

  20. You must understand how the brain will fire neurons constantly, no matter if you're blind, lost a limb, or anything else. It's neuron constantly fires and brain calculating tries to make up for losses and improvise other senses. This is the amazing human anatomy, but people tend to forget one example when you're sleeping and you're mind is in a dream. You're interpreting different realities our world that you can't comprehend, especially for those that see and those that are blind that interpret objects and colors that they cannot explain but do understand. Fortunately for us God created our anatomy with perfection to make up for what you're seeing.  Blessed our amazing brain which interpretates the visuals so you won't lose your mind . Every creation in this universe has a purpose different features which evolves .With this energy, you're not going to understand that you're a living being in a physical matter. Don't you think you have a soul? God created, but yet people still deny our Lord and creator and his amazing  creation from the Earth to the universe. Remember, our universe structure looks like the neurons of our brain. Think how small we are we only have knowledge of one Atom size of storage throughout human history, compared to what is created through every living being from here to the 7th heaven. Yet, people still deny our Lord, the most graceful and most merciful.

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