echolocation – MacGregor's Pen

On Monday’s post of “Science Explains Fantasy,” I talked about human echolocation and how some blind individuals can navigate their environments by making a series of clicking noises and listening to the echoes of the sound to detect obstacles. This method of navigation, also used by bats and dolphins, is an effective way for a visually-impaired person to explore their environment without sight.

However, learning to navigate this way takes a lot of time… so much time in fact, that the brains of experts in this method of navigation have been shown to be “rewired” to help process the information. Suffice it to say that it’s not an easy task to master. But what if mastering echolocation was as easy as putting on a belt… or seven belts, maybe? Well, it could be with the help of one friendly neighborhood…

SpiderSense. At least that’s what they’re calling the thing. Researchers at the University of Illinois Chicago have developed a device that allows anyone to be able to experience echolocation through their sense of touch. Inspired by Spider-Man’s similarly-named sixth sense that alerts him of danger (for instance, if someone were sneaking up behind him), the research team created a device that could do something similar. Take a look at the pictures below.

The above picture gives you a rough idea of what the prototype looks like. They’re a couple of bands with sensors on them (seven sensors in total), which are secured to the user’s body on the wrists, knees, head, back, chest, and shoulders. These sensors contain speakers that emanate a high-pitched sound (much like a bat does when it echolocates). The sound echoes off of nearby objects and back to the sensor, which processes the intensity of the sound. Once the sensor does some fancy math, it’s able to approximate how much distance is between itself and the object that the echo bounced off of.

To signal its wearer of the magnitude of this distance, the sensor is able to control a ratchet arm (see above photo) that presses against the wearer. If the wearer feels a small tap, this would mean that the sensor detects an object far away (a weak response from a weak signal). However, a large tap would represent a close object (a strong response from a strong signal). The video below shows it in action as one of its creators walks through a convention hall:

How good is this gadget at detecting fast-moving things in real time? Well, since the inventors of the SpiderSense were comic book enthusiasts, they decided to test the gizmo’s response time in the only way that seemed fitting: by having a blindfolded user try to hit moving people with foam ninja stars. They also ran a few more mundane tests, such as having blindfolded users walk through hallways or library stacks (as pictured above) without running into anything.

The SpiderSense is still in prototype, but it shows much promise. The concept of turning echolocation, an activity associated with hearing, into something that can be perceived through touch is quite clever. It demonstrates that although we possess or five senses, the possibilities for what we do with them are endless.

Furthermore, as a fan of fictitious echolocation specialist, Daredevil, and comics in general, I’m reminded by another startling similarity between fact and fiction. Here’s a panel of Daredevil (in red) explaining how his radar sense works:

A quick summary of his ability would be “echolocation with a tactile facet,” which is more or less what science has allowed us to develop. Granted, I’m sure that Daredevil means something a little different when he says “tactile,” but the concept that he describes is eerily similar to what we have.

Unfortunately, SpiderSense won’t hit the shelves anytime soon, but if you would like to see one in action, this video can help you build your own:

I sincerely hope that no one reading this ever has to struggle with navigating an unseen environment, but if you do, in the near future, science will be watching your back. Literally.

Jonathan MacGregor is a an adjunct instructor of chemistry in the SUNY system as well as a writer, currently seeking representation for his urban fantasy thriller, Blood of the Innocents. If you have any suggestions for future installments of Science Explains Fantasy, you may tweet to him (@JDMacGregor) using the hashtag #ScienceExplainsFantasy. Excerpts from his novel are available at his 20lines account.

Images:

SpiderSense Closeup – Image courtesy of http://i.ytimg.com/vi/XmnM9XNglOk/maxresdefault.jpg

Daredevil Comic Strip – Image courtesy of Marvel Comics, http://www.theothermurdockpapers.com/2011/10/radar-sense-present-time/

Ultrasonic Spider Sense video – courtesy of Make: at “https://www.youtube.com/embed/IJHEQuAYw6A”

Superhumans. They’ve saturated the media from the summer’s biggest blockbusters to television’s most successful programs. Last week, we discussed physical abilities common to fiction: enhanced strength and enhanced speed. But sometimes, brawn doesn’t always solve the world’s problems. And you don’t need to be physically superlative to be an Action Star. Characters like Daredevil rely on their training and sharp senses to get the job done.

action_star_by_jessica_lorraine — “Action Star” by Jessica Lorraine

But are there limits to what our senses can perceive? Or, like in the comics, can science help us unlock some untapped potential? Well, first let’s see what we can see.

Ultraviolet Vision

Usually, when people get corrective eye surgery, they expect to see what a “normal” person sees afterward. When Alek Komar received his, he was able to see extra. Alek gained the ability to see ultraviolet light, an ability we commonly witness in the animal kingdom in birds, honeybees, and other animals. However, humans lack the ability to see into the UV spectrum, because the natural lenses of our eyes absorb UV radiation, preventing it from hitting our retinas. And, if our retinas can’t detect it, we can’t see it.

However, Alek underwent surgery to replace his lens with a synthetic one that didn’t block the UV light, so, he accidentally gained the ability to see in the UV spectrum. The picture below, taken from Alek’s website, gives a rough idea of the extra colors that he’s able to see.

According to his website, where he chronicles his entire surgery experience, up to 3% of individuals who undergo this surgery can gain this ability, depending on eye sensitivity.

“But this ability doesn’t seem particularly useful,” you might say. “Wouldn’t it be better if we could see infrared light, like some cameras do?” Yes. And some people have tried this already.

Infrared Vision

Within the past few years, there has been an increased interest in transhumanism, which is defined as using scientific and technological breakthroughs to enhance human physiology. On particular team of transhumanists has recently attempted to extend the range of their eyesight to see infrared light. Their website outlines their experiment fairly well, but the gist of it goes something like this.

Your eyes use a chemical called “retinal” in order to see. Retinal changes shape when it absorbs light, and proteins in your eyes called “opsins” – which hold onto these molecules of retinal – can tell when the retinal changes shape. These opsins, which are located in your retinas, send a signal to your brain, indicating what color you saw. There are different forms of these opsins that help you distinguish different colors and wavelengths of light. Alek Komar’s, from above, were able to pick up ultraviolet light, and some people argue that maybe retinas can pick up infrared light with a little help.

The “help” in question is called vitamin A2. Your body gets its retinal – the chemical that helps you see – from vitamin A, which you get from your diet. This is why we have a saying that carrots are good for your eyesight: they’re a great source of vitamin A. However, as our transhumanist friends have pointed out in their experiment, vitamin A2 can absorb infrared light better than regular vitamin A. They suggest that if they were to change their diet, eating exclusively vitamin A2, the retinal in their eyes would slowly begin to see infrared light over time.

However, this experiment is somewhat dangerous in the sense that depriving our body of vitamin A could lead to a whole host of problems [1]. Besides that, the science has been notably called into question by a neuroscientist; you can read his criticism here. The experimenters have defended their stance reasonably well, although it should be noted that after the project’s wrap a year ago, the project’s website has not been updated with details regarding their findings.

So can humans ever hope to see infrared light? Well, we kind of already can. In this study [2], multiple scientists researching infrared radiation noted seeing flashes of green light while working with an infrared laser. After running a series of tests, they determined that under the proper conditions, the opsins of the eye can absorb infrared light as long as it was dosed in multiple, short pulses that could deliver as much energy as one pulse of visible light. This may be the consolation prize in terms of human night-vision, but at least it’s something, right?

Echolocation

Okay, so you probably won’t be able to use infrared vision to navigate through the dark anytime soon. But hey, that never stopped Daredevil, right? Heck, he can’t even see at all! What if science could somehow modify your biology so that you could navigate based on echolocation, sort of like he does? Well, it can’t. But that’s okay, because it doesn’t even have to…

For those of you who didn’t watch the above video, you just missed watching a blind man ride his bicycle through the street without any negative repercussion whatsoever. The man’s name is Daniel Kish, and he can echolocate, meaning that he can navigate in a similar fashion to a bat or a dolphin: by making a series of clicks and guessing where obstacles are based on the echoes of the sound. And the best part is, he doesn’t need any fancy equipment, he can do this all as a result of years of practice.

While it’s true that anyone can develop this skill, Daniel has been blind since a very young age, so he’s had a lot of time to practice. MRIs of echolocating individuals such as Daniel have revealed that the part of their brains that would’ve been dedicated to processing his vision have been “reassigned” [3] to helping them make sense of echoes. So, while this is a skill that anyone can learn, the people who have the best chance of excelling at it are the ones who actually need it.

The Wrap-Up

We’ve looked at people who could see ultraviolet light, people who could see infrared light, and one person who could even “see” without using light at all. The more that we explore science, the more ways we will find to surpass our limits and maybe become something more than human. Some call these people transhuman, others call them superhuman; but, either way it’s no longer fiction. Will we ever develop ultra-sharp senses just like Daredevil? That’s probably not possible, but science is making that prospect look more and more plausible with each passing day. Thank you for reading my weekly words.

Jessica Lorraine is an Alaska-based photographer and model, and you can view more of her work on her DeviantArt page.

References:

[1] Sommer, A. “Vitamin A Deficiency and Clinical Disease: An Historical Overview.” J. Nutr. 2008.
138(10). 1835-1839.

[2] Palczewska, G., et. al. “Human infrared vision is triggered by two-photon chromophore isomerization.” PNAS. 2014. 111(50). 5445-5454.

[3] Thaler, L., et al. (2011). “Neural Correlates of Natural Human Echolocation in Early and Late Blind Echolocation Experts.” PLoS ONE 6 (5): e20162.

Images:

Ultraviolet – courtesy of Alek Komar, http://www.komar.org/faq/colorado-cataract-surgery-crystalens/ultra-violet-color-glow/

Echolocation video – courtesy of perceivingacting at “https://www.youtube.com/watch?v=A8lztr1tu4o”

MacGregor's Pen

A writer's take on stories, writing, science, and life. Updates Mondays at noon.

Tag: echolocation

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