Tag Archives: extra
Google Turns 20: How an Internet Search Engine Reshaped the World
Editorial Staff | The Verge
“No technology company is arguably more responsible for shaping the modern internet, and modern life, than Google. The company that started as a novel search engine now manages eight products with more than 1 billion users each.”
Why Technology Favors Tyranny
Yuval Noah Harari | The Atlantic
“It is undoubtable…that the technological revolutions now gathering momentum will in the next few decades confront humankind with the hardest trials it has yet encountered.”
AI Can Recognize Images, But Can It Understand This Headline?
Gregory Barber | Wired
“In 2012, artificial intelligence researchers revealed a big improvement in computers’ ability to recognize images by feeding a neural network millions of labeled images from a database called ImageNet. …In other arenas of AI research, like understanding language, similar models have proved elusive. But recent research from fast.ai, OpenAI, and the Allen Institute for AI suggests a potential breakthrough, with more robust language models that can help researchers tackle a range of unsolved problems.”
Quantum Computing Is Almost Ready for Business, Startup Says
Sean Captain | Fast Company
“Rigetti is now inviting customers to apply for free access to these systems, toward the goal of developing a real-world application that achieves quantum advantage. As an extra incentive, the first to make it wins a $1 million prize.”
How Realistic Are Sci-Fi Spaceships? An Expert Ranks Your Favorites
Chris Taylor | Mashable
“For all the villainous Borg’s supposed efficiency, their vast six-sided planet-threatening vessel is a massive waste of space. The Death Star may cost an estimated $852 quadrillion in steel alone, but that figure would be far higher if it employed any other shape. That’s no moon—it’s a highly efficient use of surface area.”
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Hardly a day goes by without a research study or article published talking sh*t—or more precisely, talking about the gut microbiome. When it comes to cutting-edge innovations in medicine, all signs point to the microbiome. Maybe we should have listened to Hippocrates: “All disease begins in the gut.”
Your microbiome is mostly located in your gut and contains trillions of little guys and gals called microbes. If you want to optimize your health, biohack your body, make progress against chronic disease, or know which foods are right for you—almost all of this information can be found in your microbiome.
My company, Viome, offers technology to measure your microscopic organisms and their behavior at a molecular level. Think of it as the Instagram of your inner world. A snapshot of what’s happening inside your body. New research about the microbiome is changing our understanding of who we are as humans and how the human body functions.
It turns out the microbiome may be mission control for your body and mind. Your healthy microbiome is part best friend, part power converter, part engine, and part pharmacist. At Viome, we’re working to analyze these microbial functions and recommend a list of personalized food and supplements to keep these internal complex machines in a finely tuned balance.
We now have more information than ever before about what your microbiome is doing, and it’s going to help you and the rest of the world do a whole lot better. The new insights emerging from microbiome research are changing our perception of what keeps us healthy and what makes us sick. This new understanding of the microbiome activities may put an end to conflicting food advice and make fad diets a thing of the past.
What are these new insights showing us? The information is nothing short of mind-blowing. The value of your poop just got an upgrade.
Here are some of the amazing things we’ve learned from our work at Viome.
1. Was Popeye wrong? Why “health food” isn’t necessarily healthy.
Each week there is a new fad diet released, discussed, and followed. The newest “research” shows that this is now the superfood to eat for everyone. But, too often, the fad diet is just a regurgitation of what worked for one person and shouldn’t be followed by everyone else.
For example, we’ve been told to eat our greens and that greens and nuts are “anti-inflammatory,” but this is actually not always true. Spinach, bran, rhubarb, beets, nuts, and nut butters all contain oxalate. We now know that oxalate-containing food can be harmful, unless you have the microbes present that can metabolize it into a non-harmful substance.
30% of Viome customers do not have the microbes to metabolize oxalates properly. In other words, “healthy foods” like spinach are actually not healthy for these people.
Looks like not everyone should follow Popeye’s food plan.
2. Aren’t foods containing “antioxidants” always good for everyone?
Just like oxalates, polyphenols in foods are usually considered very healthy, but unless you have microbes that utilize specific polyphenols, you may not get full benefit from them. One example is a substance found in these foods called ellagic acid. We can detect if your microbiome is metabolizing ellagic acid and converting it into urolithin A. It is only the urolithin A that has anti-inflammatory and antioxidant effects. Without the microbes to do this conversion you will not benefit from the ellagic acid in foods.
Examples: Walnuts, raspberries, pomegranate, blackberries, pecans, and cranberries all contain ellagic acid.
We have analyzed tens of thousands of people, and only about 50% of the people actually benefit from eating more foods containing ellagic acid.
3. You’re probably eating too much protein (and it may be causing inflammation).
When you think high-protein diet, you think paleo, keto, and high-performance diets.
Protein is considered good for you. It helps build muscle and provide energy—but if you eat too much, it can cause inflammation and decrease longevity.
We can analyze the activity of your microbiome to determine if you are eating too much protein that feeds protein-fermenting bacteria like Alistipes putredinis and Tannerella forsythia, and if these organisms are producing harmful substances such as ammonia, hydrogen sulfide, p-cresol, or putrescine. These substances can damage your gut lining and lead to things like leaky gut.
4. Something’s fishy. Are “healthy foods” causing heart disease?
Choline in certain foods can get converted by bacteria into a substance called trimethylamine (TMA) that is associated with heart disease when it gets absorbed into your body and converted to TMAO. However, TMA conversion doesn’t happen in individuals without these types of bacteria in their microbiome.
We can see the TMA production pathways and many of the gammaproteobacteria that do this conversion.
What foods contain choline? Liver, salmon, chickpeas, split peas, eggs, navy beans, peanuts, and many others.
Before you decide to go full-on pescatarian or paleo, you may want to check if your microbiome is producing TMA with that salmon or steak.
5. Hold up, Iron Man. We can see inflammation from too much iron.
Minerals like iron in your food can, in certain inflammatory microbial environments, promote growth of pathogens like Esherichia, Shigella, and Salmonella.
Maybe it wasn’t just that raw chicken that gave you food poisoning, but your toxic microbiome that made you sick.
On the other hand, when you don’t have enough iron, you could become anemic leading to weakness and shortness of breath.
So, just like Iron Man, it’s about finding your balance so that you can fly.
6. Are you anxious or stressed? Your poop will tell you.
Our gut and brain are connected via the vagus nerve. A large majority of neurotransmitters are either produced or consumed by our microbiome. In fact, some 90% of all serotonin (a feel-good neurotransmitter) is produced by your gut microbiome and not by your brain.
When you have a toxic microbiome that’s producing a large amount of toxins like hydrogen sulfide, the lining of your gut starts to deteriorate into what’s known as leaky gut. Think of leaky gut as your gut not having healthy borders or boundaries. And when this happens, all kinds of disease can emerge. When the barrier of the gut breaks down, it starts a chain reaction causing low-grade chronic inflammation—which has been identified as a potential source of depression and higher levels of anxiety, in addition to many other chronic diseases.
We’re not saying you shouldn’t meditate, but if you want to get the most out of your meditation and really reduce your stress levels, make sure you are eating the right food that promotes a healthy microbiome.
7. Your microbiome is better than Red Bull.
If you want more energy, get your microbiome back into balance.
No you don’t need three pots of coffee to keep you going, you just need a balanced microbiome.
Your microbiome is responsible for calorie extraction, or creating energy, through pathways such as the Tricarboxylic acid cycle. Our bodies depend on the energy that our microbiome produces.
How much energy we get from our food is dependent on how efficient our microbiome is at converting the food into energy. High-performing microbiomes are excellent at converting food into energy. This is great when you are an athlete and need the extra energy, but if you don’t use up the energy it may be the source of some of those unwanted pounds.
If the microbes can’t or won’t metabolize the glucose (sugar) that you eat, it will be stored as fat. If the microbes are extracting too many calories from your food or producing lipopolysaccharides (LPS) and causing metabolic endotoxemia leading to activation of toll-like receptors and insulin resistance you may end up storing what you eat as fat.
Think of your microbiome as Doc Brown’s car from the future—it can take pretty much anything and turn it into fuel if it’s strong and resilient enough.
8. We can see your joint pain in your poop.
Got joint pain? Your microbiome can tell you why.
Lipopolysaccharide (LPS) is a key pro-inflammatory molecule made by some of your microbes. If your microbes are making too much LPS, it can wreak havoc on your immune system by putting it into overdrive. When your immune system goes on the warpath there is often collateral damage to your joints and other body parts.
Perhaps balancing your microbiome is a better solution than reaching for the glucosamine. Think of your microbiome as the top general of your immune army. It puts your immune system through basic training and determines when it goes to war.
Ideally, your immune system wins the quick battle and gets some rest, but sometimes if your microbiome keeps it on constant high alert it becomes a long, drawn-out war resulting in chronic inflammation and chronic diseases.
Are you really “getting older” or is your microbiome just making you “feel” older because it keeps giving warnings to your immune system ultimately leading to chronic pain?
Before you throw in the towel on your favorite activities, check your microbiome. And, if you have anything with “itis” in it, it’s possible that when you balance your microbiome the inflammation from your “itis” will be reduced.
9. Your gut is doing the talking for your mouth.
When you have low stomach acid, your mouth bacteria makes it down to your GI tract.
Stomach acid is there to protect you from the bacteria in your mouth and the parasites and fungi that are in your food. If you don’t have enough of it, the bacteria in your mouth will invade your gut. This invasion is associated with and a risk factor for autoimmune disease and inflammation in the gut.
We are learning that low stomach acid is perhaps one of the major causes of chronic disease. This stomach acid is essential to kill mouth bacteria and help us digest our food.
What kinds of things cause low stomach acid? Stress and antacids like Nexium, Zantac, and Prilosec.
10. Carbs can be protein precursors.
Rejoice! Perhaps carbs aren’t as bad as we thought (as long as your microbiome is up to the task). We can see if some of the starches you eat can be made into amino acids by the microbiome.
Our microbiome makes 20% of our branched-chain amino acids (BCAAs) for us, and it will adapt to make these vital BCAAs for us in almost any way it can.
Essentially, your microbiome is hooking up carbons and hydrogens into different formulations of BCAAs, depending on what you feed it. The microbiome is excellent at adapting and pivoting based on the food you feed it and the environment that it’s in.
So, good news: Carbs are protein precursors, as long as you have the right microbiome.
Stop Talking Sh*t Now
Your microbiome is a world class entrepreneur that can take low-grade sources of food and turn them into valuable and useable energy.
You have a best friend and confidant within you that is working wonders to make sure you have energy and that all of your needs are met.
And, just like a best friend, if you take great care of your microbiome, it will take great care of you.
Given the research emerging daily about the microbiome and its importance on your quality of life, prioritizing the health of your microbiome is essential.
When you have a healthy microbiome, you’ll have a healthy life.
It’s now clear that some of the greatest insights for your health will come from your poop.
It’s time to stop talking sh*t and get your sh*t together. Your life may depend on it.
Viome can help you identify what your microbiome is actually doing. The combination of Viome’s metatranscriptomic technology and cutting-edge artificial intelligence is paving a brand new path forward for microbiome health.
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As artificial intelligence advances, we’re encountering the same old questions. How much of what we consider to be fundamentally human can be reduced to an algorithm? Can we create something sufficiently advanced that people can no longer distinguish between the two? This, after all, is the idea behind the Turing Test, which has yet to be passed.
At first glance, you might think music is beyond the realm of algorithms. Birds can sing, and people can compose symphonies. Music is evocative; it makes us feel. Very often, our intense personal and emotional attachments to music are because it reminds us of our shared humanity. We are told that creative jobs are the least likely to be automated. Creativity seems fundamentally human.
But I think above all, we view it as reductionist sacrilege: to dissect beautiful things. “If you try to strangle a skylark / to cut it up, see how it works / you will stop its heart from beating / you will stop its mouth from singing.” A human musician wrote that; a machine might be able to string words together that are happy or sad; it might even be able to conjure up a decent metaphor from the depths of some neural network—but could it understand humanity enough to produce art that speaks to humans?
Then, of course, there’s the other side of the debate. Music, after all, has a deeply mathematical structure; you can train a machine to produce harmonics. “In the teachings of Pythagoras and his followers, music was inseparable from numbers, which were thought to be the key to the whole spiritual and physical universe,” according to Grout in A History of Western Music. You might argue that the process of musical composition cannot be reduced to a simple algorithm, yet musicians have often done so. Mozart, with his “Dice Music,” used the roll of a dice to decide how to order musical fragments; creativity through an 18th-century random number generator. Algorithmic music goes back a very long way, with the first papers on the subject from the 1960s.
Then there’s the techno-enthusiast side of the argument. iTunes has 26 million songs, easily more than a century of music. A human could never listen to and learn from them all, but a machine could. It could also memorize every note of Beethoven. Music can be converted into MIDI files, a nice chewable data format that allows even a character-by-character neural net you can run on your computer to generate music. (Seriously, even I could get this thing working.)
Indeed, generating music in the style of Bach has long been a test for AI, and you can see neural networks gradually learn to imitate classical composers while trying to avoid overfitting. When an algorithm overfits, it essentially starts copying the existing music, rather than being inspired by it but creating something similar: a tightrope the best human artists learn to walk. Creativity doesn’t spring from nowhere; even maverick musical geniuses have their influences.
Does a machine have to be truly ‘creative’ to produce something that someone would find valuable? To what extent would listeners’ attitudes change if they thought they were hearing a human vs. an AI composition? This all suggests a musical Turing Test. Of course, it already exists. In fact, it’s run out of Dartmouth, the school that hosted that first, seminal AI summer conference. This year, the contest is bigger than ever: alongside the PoetiX, LimeriX and LyriX competitions for poetry and lyrics, there’s a DigiKidLit competition for children’s literature (although you may have reservations about exposing your children to neural-net generated content… it can get a bit surreal).
There’s also a pair of musical competitions, including one for original compositions in different genres. Key genres and styles are represented by Charlie Parker for Jazz and the Bach chorales for classical music. There’s also a free composition, and a contest where a human and an AI try to improvise together—the AI must respond to a human spontaneously, in real time, and in a musically pleasing way. Quite a challenge! In all cases, if any of the generated work is indistinguishable from human performers, the neural net has passed the Turing Test.
Did they? Here’s part of 2017’s winning sonnet from Charese Smiley and Hiroko Bretz:
The large cabin was in total darkness.
Come marching up the eastern hill afar.
When is the clock on the stairs dangerous?
Everything seemed so near and yet so far.
Behind the wall silence alone replied.
Was, then, even the staircase occupied?
Generating the rhymes is easy enough, the sentence structure a little trickier, but what’s impressive about this sonnet is that it sticks to a single topic and appears to be a more coherent whole. I’d guess they used associated “lexical fields” of similar words to help generate something coherent. In a similar way, most of the more famous examples of AI-generated music still involve some amount of human control, even if it’s editorial; a human will build a song around an AI-generated riff, or select the most convincing Bach chorale from amidst many different samples.
We are seeing strides forward in the ability of AI to generate human voices and human likenesses. As the latter example shows, in the fake news era people have focused on the dangers of this tech– but might it also be possible to create a virtual performer, trained on a dataset of their original music? Did you ever want to hear another Beatles album, or jam with Miles Davis? Of course, these things are impossible—but could we create a similar experience that people would genuinely value? Even, to the untrained eye, something indistinguishable from the real thing?
And if it did measure up to the real thing, what would this mean? Jaron Lanier is a fascinating technology writer, a critic of strong AI, and a believer in the power of virtual reality to change the world and provide truly meaningful experiences. He’s also a composer and a musical aficionado. He pointed out in a recent interview that translation algorithms, by reducing the amount of work translators are commissioned to do, have, in some sense, profited from stolen expertise. They were trained on huge datasets purloined from human linguists and translators. If you can train an AI on someone’s creative output and it produces new music, who “owns” it?
Although companies that offer AI music tools are starting to proliferate, and some groups will argue that the musical Turing test has been passed already, AI-generated music is hardly racing to the top of the pop charts just yet. Even as the line between human-composed and AI-generated music starts to blur, there’s still a gulf between the average human and musical genius. In the next few years, we’ll see how far the current techniques can take us. It may be the case that there’s something in the skylark’s song that can’t be generated by machines. But maybe not, and then this song might need an extra verse.
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For every new piece of technology that gets developed, you can usually find people saying it will never be useful. The president of the Michigan Savings Bank in 1903, for example, said, “The horse is here to stay but the automobile is only a novelty—a fad.” It’s equally easy to find people raving about whichever new technology is at the peak of the Gartner Hype Cycle, which tracks the buzz around these newest developments and attempts to temper predictions. When technologies emerge, there are all kinds of uncertainties, from the actual capacity of the technology to its use cases in real life to the price tag.
Eventually the dust settles, and some technologies get widely adopted, to the extent that they can become “invisible”; people take them for granted. Others fall by the wayside as gimmicky fads or impractical ideas. Picking which horses to back is the difference between Silicon Valley millions and Betamax pub-quiz-question obscurity. For a while, it seemed that Google had—for once—backed the wrong horse.
Google Glass emerged from Google X, the ubiquitous tech giant’s much-hyped moonshot factory, where highly secretive researchers work on the sci-fi technologies of the future. Self-driving cars and artificial intelligence are the more mundane end for an organization that apparently once looked into jetpacks and teleportation.
The original smart glasses, Google began selling Google Glass in 2013 for $1,500 as prototypes for their acolytes, around 8,000 early adopters. Users could control the glasses with a touchpad, or, activated by tilting the head back, with voice commands. Audio relay—as with several wearable products—is via bone conduction, which transmits sound by vibrating the skull bones of the user. This was going to usher in the age of augmented reality, the next best thing to having a chip implanted directly into your brain.
On the surface, it seemed to be a reasonable proposition. People had dreamed about augmented reality for a long time—an onboard, JARVIS-style computer giving you extra information and instant access to communications without even having to touch a button. After smartphone ubiquity, it looked like a natural step forward.
Instead, there was a backlash. People may be willing to give their data up to corporations, but they’re less pleased with the idea that someone might be filming them in public. The worst aspect of smartphones is trying to talk to people who are distractedly scrolling through their phones. There’s a famous analogy in Revolutionary Road about an old couple’s loveless marriage: the husband tunes out his wife’s conversation by turning his hearing aid down to zero. To many, Google Glass seemed to provide us with a whole new way to ignore each other in favor of our Twitter feeds.
Then there’s the fact that, regardless of whether it’s because we’re not used to them, or if it’s a more permanent feature, people wearing AR tech often look very silly. Put all this together with a lack of early functionality, the high price (do you really feel comfortable wearing a $1,500 computer?), and a killer pun for the users—Glassholes—and the final recipe wasn’t great for Google.
Google Glass was quietly dropped from sale in 2015 with the ominous slogan posted on Google’s website “Thanks for exploring with us.” Reminding the Glass users that they had always been referred to as “explorers”—beta-testing a product, in many ways—it perhaps signaled less enthusiasm for wearables than the original, Google Glass skydive might have suggested.
In reality, Google went back to the drawing board. Not with the technology per se, although it has improved in the intervening years, but with the uses behind the technology.
Under what circumstances would you actually need a Google Glass? When would it genuinely be preferable to a smartphone that can do many of the same things and more? Beyond simply being a fashion item, which Google Glass decidedly was not, even the most tech-evangelical of us need a convincing reason to splash $1,500 on a wearable computer that’s less socially acceptable and less easy to use than the machine you’re probably reading this on right now.
Enter the Google Glass Enterprise Edition.
Piloted in factories during the years that Google Glass was dormant, and now roaring back to life and commercially available, the Google Glass relaunch got under way in earnest in July of 2017. The difference here was the specific audience: workers in factories who need hands-free computing because they need to use their hands at the same time.
In this niche application, wearable computers can become invaluable. A new employee can be trained with pre-programmed material that explains how to perform actions in real time, while instructions can be relayed straight into a worker’s eyeline without them needing to check a phone or switch to email.
Medical devices have long been a dream application for Google Glass. You can imagine a situation where people receive real-time information during surgery, or are augmented by artificial intelligence that provides additional diagnostic information or questions in response to a patient’s symptoms. The quest to develop a healthcare AI, which can provide recommendations in response to natural language queries, is on. The famously untidy doctor’s handwriting—and the associated death toll—could be avoided if the glasses could take dictation straight into a patient’s medical records. All of this is far more useful than allowing people to check Facebook hands-free while they’re riding the subway.
Google’s “Lens” application indicates another use for Google Glass that hadn’t quite matured when the original was launched: the Lens processes images and provides information about them. You can look at text and have it translated in real time, or look at a building or sign and receive additional information. Image processing, either through neural networks hooked up to a cloud database or some other means, is the frontier that enables driverless cars and similar technology to exist. Hook this up to a voice-activated assistant relaying information to the user, and you have your killer application: real-time annotation of the world around you. It’s this functionality that just wasn’t ready yet when Google launched Glass.
Amazon’s recent announcement that they want to integrate Alexa into a range of smart glasses indicates that the tech giants aren’t ready to give up on wearables yet. Perhaps, in time, people will become used to voice activation and interaction with their machines, at which point smart glasses with bone conduction will genuinely be more convenient than a smartphone.
But in many ways, the real lesson from the initial failure—and promising second life—of Google Glass is a simple question that developers of any smart technology, from the Internet of Things through to wearable computers, must answer. “What can this do that my smartphone can’t?” Find your answer, as the Enterprise Edition did, as Lens might, and you find your product.
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Ask any neuroscientist to draw you a neuron, and it’ll probably look something like a star with two tails: one stubby with extensive tree-like branches, the other willowy, lengthy and dotted with spindly spikes.
While a decent abstraction, this cartoonish image hides the uncomfortable truth that scientists still don’t know much about what many neurons actually look like, not to mention the extent of their connections.
But without untangling the jumbled mess of neural wires that zigzag across the brain, scientists are stumped in trying to answer one of the most fundamental mysteries of the brain: how individual neuronal threads carry and assemble information, which forms the basis of our thoughts, memories, consciousness, and self.
What if there was a way to virtually trace and explore the brain’s serpentine fibers, much like the way Google Maps allows us to navigate the concrete tangles of our cities’ highways?
Thanks to an interdisciplinary team at Janelia Research Campus, we’re on our way. Meet MouseLight, the most extensive map of the mouse brain ever attempted. The ongoing project has an ambitious goal: reconstructing thousands—if not more—of the mouse’s 70 million neurons into a 3D map. (You can play with it here!)
With map in hand, neuroscientists around the world can begin to answer how neural circuits are organized in the brain, and how information flows from one neuron to another across brain regions and hemispheres.
The first release, presented Monday at the Society for Neuroscience Annual Conference in Washington, DC, contains information about the shape and sizes of 300 neurons.
And that’s just the beginning.
“MouseLight’s new dataset is the largest of its kind,” says Dr. Wyatt Korff, director of project teams. “It’s going to change the textbook view of neurons.”
MouseLight is hardly the first rodent brain atlasing project.
The Mouse Brain Connectivity Atlas at the Allen Institute for Brain Science in Seattle tracks neuron activity across small circuits in an effort to trace a mouse’s connectome—a complete atlas of how the firing of one neuron links to the next.
MICrONS (Machine Intelligence from Cortical Networks), the $100 million government-funded “moonshot” hopes to distill brain computation into algorithms for more powerful artificial intelligence. Its first step? Brain mapping.
What makes MouseLight stand out is its scope and level of detail.
MICrONS, for example, is focused on dissecting a cubic millimeter of the mouse visual processing center. In contrast, MouseLight involves tracing individual neurons across the entire brain.
And while connectomics outlines the major connections between brain regions, the birds-eye view entirely misses the intricacies of each individual neuron. This is where MouseLight steps in.
Slice and Dice
With a width only a fraction of a human hair, neuron projections are hard to capture in their native state. Tug or squeeze the brain too hard, and the long, delicate branches distort or even shred into bits.
In fact, previous attempts at trying to reconstruct neurons at this level of detail topped out at just a dozen, stymied by technological hiccups and sky-high costs.
A few years ago, the MouseLight team set out to automate the entire process, with a few time-saving tweaks. Here’s how it works.
After injecting a mouse with a virus that causes a handful of neurons to produce a green-glowing protein, the team treated the brain with a sugar alcohol solution. This step “clears” the brain, transforming the beige-colored organ to translucent, making it easier for light to penetrate and boosting the signal-to-background noise ratio. The brain is then glued onto a small pedestal and ready for imaging.
Building upon an established method called “two-photon microscopy,” the team then tweaked several parameters to reduce imaging time from days (or weeks) down to a fraction of that. Endearingly known as “2P” by the experts, this type of laser microscope zaps the tissue with just enough photos to light up a single plane without damaging the tissue—sharper plane, better focus, crisper image.
After taking an image, the setup activates its vibrating razor and shaves off the imaged section of the brain—a waspy slice about 200 micrometers thick. The process is repeated until the whole brain is imaged.
This setup increased imaging speed by 16 to 48 times faster than conventional microscopy, writes team leader Dr. Jayaram Chandrashekar, who published a version of the method early last year in eLife.
The resulting images strikingly highlight every crook and cranny of a neuronal branch, popping out against a pitch-black background. But pretty pictures come at a hefty data cost: each image takes up a whopping 20 terabytes of data—roughly the storage space of 4,000 DVDs, or 10,000 hours of movies.
Stitching individual images back into 3D is an image-processing nightmare. The MouseLight team used a combination of computational power and human prowess to complete this final step.
The reconstructed images are handed off to a mighty team of seven trained neuron trackers. With the help of tracing algorithms developed in-house and a keen eye, each member can track roughly a neuron a day—significantly less time than the week or so previously needed.
A Numbers Game
Even with just 300 fully reconstructed neurons, MouseLight has already revealed new secrets of the brain.
While it’s widely accepted that axons, the neurons’ outgoing projection, can span the entire length of the brain, these extra-long connections were considered relatively rare. (In fact, one previously discovered “giant neuron” was thought to link to consciousness because of its expansive connections).
Images captured from two-photon microscopy show an axon and dendrites protruding from a neuron’s cell body (sphere in center). Image Credit: Janelia Research Center, MouseLight project team
MouseLight blows that theory out of the water.
The data clearly shows that “giant neurons” are far more common than previously thought. For example, four neurons normally associated with taste had wiry branches that stretched all the way into brain areas that control movement and process touch.
“We knew that different regions of the brain talked to each other, but seeing it in 3D is different,” says Dr. Eve Marder at Brandeis University.
“The results are so stunning because they give you a really clear view of how the whole brain is connected.”
With a tested and true system in place, the team is now aiming to add 700 neurons to their collection within a year.
But appearance is only part of the story.
We can’t tell everything about a person simply by how they look. Neurons are the same: scientists can only infer so much about a neuron’s function by looking at their shape and positions. The team also hopes to profile the gene expression patterns of each neuron, which could provide more hints to their roles in the brain.
MouseLight essentially dissects the neural infrastructure that allows information traffic to flow through the brain. These anatomical highways are just the foundation. Just like Google Maps, roads form only the critical first layer of the map. Street view, traffic information and other add-ons come later for a complete look at cities in flux.
The same will happen for understanding our ever-changing brain.
Image Credit: Janelia Research Campus, MouseLight project team Continue reading