from the world's big
Scientists create holographic projections in the brain that can create false memories
Researchers say they’ll someday be able to recreate experiences, perceptions, and sensations with a device the size of a backpack.
We’ve all seen sci-fi movies like Total Recall and Eternal Sunshine of the Spotless Mind, where a character has their memory erased. An even more frightening troupe, sometimes a character is imbued with a false memory. Though usually relegated to the world of the fantastical, real life scientists today believe they have a machine that can do such things, what’s known as a holographic brain modulator.
Researchers at UC Berkley have been developing it, the details of which were published recently in the journal, Nature Communications. There is definitely tons of room for misuse here, but the machine could also garner incredible benefits, such as helping patients regain lost memories, or even senses. It’s also likely to vault neuroscience research into the stratosphere.
The brain modulator monitors and then alters neural activity. It does this by isolating certain sets of neurons, at first dozens, then hundreds, and then thousands at a time, and stimulating them in particular patterns that mimic authentic brain activity. As a result, it is able to trick the brain into believing it had sensed, seen, or experienced an event or phenomenon which never occurred.
For those who have lost a sense or a limb, this could be a godsend. Consider an amputee who has an artificial arm. Such technology could restore the sense of touch. What about a blind person who gets a robotic eye? This breakthrough could help gather and interpret visual data for the brain, allowing the eye to work just like a real one.
We usually think of holograms as 3D images floating in space, but it’s actually the bending of light into certain 3D shapes. Image credit: Getty Images.
Alan Mardinly is a doctoral student at UC Berkeley and one of three co-authors on the project. He said in a press release,
This has great potential for neural prostheses, since it has the precision needed for the brain to interpret the pattern of activation. If you can read and write the language of the brain, you can speak to it in its own language and it can interpret the message much better. This is one of the first steps in a long road to develop a technology that could be a virtual brain implant with additional senses or enhanced senses.
So far, it’s been tested on laboratory mice. With their heads immobilized, they were made to walk on treadmills. UC Berkeley scientists then used this technique to target specific neurons, stimulating the surface of a part of the brain called the somatosensory cortex. This is an area just a tenth of a millimeter thick. It’s the brain’s motor center, which controls things like vision and touch.
Scientists placed holographic obstacles in the mice’s way as they were walking. This took place inside their brains, like an illusion. Although the scientists noticed no change in behavior, monitoring showed that that each mouse’s brain responded as if the obstacle was real. Now, UC Berkeley scientists are developing ways in which to accurately detect behavior after a mouse has been stimulated with the device.
Computer generated holography was used to simulate the obstacles. Holography is the practice of bending and focusing light into 3D shapes. The process works by focusing attention on a 3D area of the brain, consisting of thousands of different neurons. From there, singular neurons are selected, each about the width of a human hair. The modulator activates 50 of them at a time using a 3D laser technique. First one jumble of 50 is activated, then another and another. It repeats this action up to 300 times per second.
The technique the machine uses to generate the hologram is called: three-dimensional scanless holographic optogenetics with temporal focusing (3D-SHOT). First, a liquid crystal screen is set up. This acts something like a photographic negative, but is instead a holographic one. Using the negative, scientists’ shape the light from 40W lasers into whatever 3D pattern they’ve chosen, inside the brain. Laser pulses are shot out every microsecond in bursts that last a mere femtosecond (one quadrillionth of a second), in order to maintain the hologram.
A sample hologram with 50 randomly distributed neuron targets spanning a region 500 microns square and 250 microns deep. Image Credit: UC Berkeley.
The biggest breakthrough was isolating certain individual neurons and causing them to fire without affecting their neighbors. The ability to target neurons precisely is a major advancement that will likely inspire other innovations. So far, researchers have only tested the technique on a small portion of the brain. Much more research must be done to prove it can stimulate other areas. What’s more, the machine is enormous in size.
UC Berkeley scientists however, believe that over time, they’ll be able to scale it down to the size of a knapsack. They’ll also record different patterns and cause a mouse’s brain to play them back, in order to see if each particular pattern always results in the same response. They believe that in time they’ll have the ability to control neural activity in the cortex, and so be able to recreate any perception or sensation one can think of.
Want to see video footage showing scientists using this technique in the somatosensory cortex of a mouse’s brain? Click below. (Note that activated neurons glow fluoresce green, while the purple arrow indicates the laser light activating them).
What would it be like to experience the 4th dimension?
Physicists have understood at least theoretically, that there may be higher dimensions, besides our normal three. The first clue came in 1905 when Einstein developed his theory of special relativity. Of course, by dimensions we’re talking about length, width, and height. Generally speaking, when we talk about a fourth dimension, it’s considered space-time. But here, physicists mean a spatial dimension beyond the normal three, not a parallel universe, as such dimensions are mistaken for in popular sci-fi shows.
If machines develop consciousness, or if we manage to give it to them, the human-robot dynamic will forever be different.
- Does AI—and, more specifically, conscious AI—deserve moral rights? In this thought exploration, evolutionary biologist Richard Dawkins, ethics and tech professor Joanna Bryson, philosopher and cognitive scientist Susan Schneider, physicist Max Tegmark, philosopher Peter Singer, and bioethicist Glenn Cohen all weigh in on the question of AI rights.
- Given the grave tragedy of slavery throughout human history, philosophers and technologists must answer this question ahead of technological development to avoid humanity creating a slave class of conscious beings.
- One potential safeguard against that? Regulation. Once we define the context in which AI requires rights, the simplest solution may be to not build that thing.
Duke University researchers might have solved a half-century old problem.
- Duke University researchers created a hydrogel that appears to be as strong and flexible as human cartilage.
- The blend of three polymers provides enough flexibility and durability to mimic the knee.
- The next step is to test this hydrogel in sheep; human use can take at least three years.
Duke researchers have developed the first gel-based synthetic cartilage with the strength of the real thing. A quarter-sized disc of the material can withstand the weight of a 100-pound kettlebell without tearing or losing its shape.
Photo: Feichen Yang.<p>That's the word from a team in the Department of Chemistry and Department of Mechanical Engineering and Materials Science at Duke University. Their <a href="https://onlinelibrary.wiley.com/doi/abs/10.1002/adfm.202003451" target="_blank">new paper</a>, published in the journal,<em> Advanced Functional Materials</em>, details this exciting evolution of this frustrating joint.<br></p><p>Researchers have sought materials strong and versatile enough to repair a knee since at least the seventies. This new hydrogel, comprised of three polymers, might be it. When two of the polymers are stretched, a third keeps the entire structure intact. When pulled 100,000 times, the cartilage held up as well as materials used in bone implants. The team also rubbed the hydrogel against natural cartilage a million times and found it to be as wear-resistant as the real thing. </p><p>The hydrogel has the appearance of Jell-O and is comprised of 60 percent water. Co-author, Feichen Yang, <a href="https://today.duke.edu/2020/06/lab-first-cartilage-mimicking-gel-strong-enough-knees" target="_blank">says</a> this network of polymers is particularly durable: "Only this combination of all three components is both flexible and stiff and therefore strong." </p><p> As with any new material, a lot of testing must be conducted. They don't foresee this hydrogel being implanted into human bodies for at least three years. The next step is to test it out in sheep. </p><p>Still, this is an exciting step forward in the rehabilitation of one of our trickiest joints. Given the potential reward, the wait is worth it. </p><p><span></span>--</p><p><em>Stay in touch with Derek on <a href="http://www.twitter.com/derekberes" target="_blank">Twitter</a>, <a href="https://www.facebook.com/DerekBeresdotcom" target="_blank">Facebook</a> and <a href="https://derekberes.substack.com/" target="_blank">Substack</a>. His next book is</em> "<em>Hero's Dose: The Case For Psychedelics in Ritual and Therapy."</em></p>
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