How Our Brains Feel Emotion
Antonio Damasio
Dr. Antonio Damasio is a renowned neuroscientist who direct's the USC Brain and Creativity Institute. Before that he was the Head of Neurology at the University of Iowa Hospitals and Clinics. His research focuses on the neurobiology of mind and behavior, with an emphasis on emotion, decision-making, memory, communication, and creativity. His research has helped describe the neurological origins of emotions and has shown how emotions affect cognition and decision-making. He is the author of a number of books, including "Self Comes to Mind: Constructing the Conscious Brain," which will be published in November, 2010. Dr. Damasio is also the 2010 winner of the Honda Prize, one of the most important international awards for scientific achievement.
Dr. Damasio is a Big Think Delphi Fellow.
Question: What is happening in our brain when we feel an emotion?
Antonio Damasio: Feeling of an emotion is a process that is distinct from having the emotion in the first place. So it helps to understand what is an emotion, what is a feeling, we need to understand what is an emotion. And the emotion is the execution of a very complex program of actions. Some actions that are actually movements, like movement that you can do, change your face for example, in fear, or movements that are internal, that happen in your heart or in your gut, and movements that are actually not muscular movements, but rather, releases of molecules. Say, for example, in the endocrine system into the blood stream, but it’s movement and action in the broad sense of the term.
And an emotion consists of a very well orchestrated set of alterations in the body that has, as a general purpose, making life more survivable by taking care of a danger, of taking care of an opportunity, either/or, or something in between. And it’s something that is set in our genome and that we all have with a certain programmed nature that is modified by our experience so individually we have variations on the pattern. But in essence, your emotion of joy and mine are going to be extremely similar. We may express them physically slightly differently, and it’s of course graded depending on the circumstance, but the essence of the process is going to be the same, unless one of us is not quite well put together and is missing something, otherwise it’s going to be the same.
And it’s going to be the same across even other species. You know, there’s a, you know, we may smile and the dog may wag the tail, but in essence, we have a set program and those programs are similar across individuals in the species.
Then the feeling is actually a portrayal of what is going on in the organs when you are having an emotion. So it’s really the next thing that happens. If you have just an emotion, you would not necessarily feel it. To feel an emotion, you need to represent in the brain in structures that are actually different from the structures that lead to the emotion, what is going on in the organs when you’re having the emotion. So, you can define it very simply as the process of perceiving what is going on in the organs when you are in the throws of an emotion, and that is achieved by a collection of structures, some of which are in the brain stem, and some of which are in the cerebral cortex, namely the insular cortex, which I like to mention not because I think it’s the most important, it’s not. I actually don’t think it’s the number one structure controlling our feelings, but I like to mention because it’s something that people didn’t really know about and many years ago, which probably now are going close to 20 years ago, I thought that the insular would be an important platform for feelings, that’s where I started. And it was a hypothesis and it turns out that the hypothesis is perfectly correct. And 10 years ago, we had the first experiments that showed that it was indeed so, and since then, countless studies have shown that when you’re having feelings of an emotion or feelings of a variety of other things, the insular is active, but it doesn’t mean that it’s the only thing that is active and there are other structures that are very important as well.
Recorded July 2, 2010
Interviewed by David Hirschman
An emotion consists of a very well orchestrated set of alterations in the body. Its purpose is to make life more survivable by taking care of a danger or taking advantage of an opportunity.
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How New York's largest hospital system is predicting COVID-19 spikes
Northwell Health is using insights from website traffic to forecast COVID-19 hospitalizations two weeks in the future.
14 January, 2021
Credit: Getty Images
Sponsored by Northwell Health
- The machine-learning algorithm works by analyzing the online behavior of visitors to the Northwell Health website and comparing that data to future COVID-19 hospitalizations.
- The tool, which uses anonymized data, has so far predicted hospitalizations with an accuracy rate of 80 percent.
- Machine-learning tools are helping health-care professionals worldwide better constrain and treat COVID-19.
<p>One of the most devastating aspects of the COVID-19 pandemic has been unpredictability. The nation's health systems—especially those in hard-hit areas like New York City—have had to adapt to sudden surges of COVID-19 cases, all while dealing with limited resources, existing patients, and a novel virus that's still not fully understood.</p><p>But what if health systems were able to forecast COVID-19 hospitalizations two weeks before they occur? Northwell Health, the largest health care system in New York state, recently deployed a predictive tool that does just that.</p><p>Northwell Health's <a href="https://www.northwell.edu/northwell-website-patterns-predict-covid-19-cases" target="_blank">surveillance dashboard</a> is able to predict COVID-19 hospitalizations by using insights from machine learning. In March, Northwell Health's Customer Insights Group developed an algorithm that's been mining data from online traffic to the Northwell.edu website, which has received more than 20 million hits since March.<strong></strong></p><p>The algorithm collects data through 15 different indicators, each of which reflects the online behavior of the website's visitors. For example, the tool analyzes metrics such as the length of time users spend on certain pages, searches for emergency department wait times, and specific symptoms users search for. Combined, this information translates into something like the "public mood" of the website on any given day.</p>
<blockquote>Since Northwell Health began using the predictive tool in September, it's predicted COVID-19 hospitalizations with an accuracy of about 80 percent.</blockquote>
<p>To understand how this mood relates to future COVID-19 cases, Northwell Health began comparing its data with a timeline of COVID-19 hospitalizations across 23 hospitals and nearly 800 outpatient facilities and in the metro New York area. This enabled the Customer Insights Group to see patterns of online activity that precede future increases or decreases in hospitalizations.</p><p>Since Northwell Health began using the predictive tool in September, it's predicted COVID-19 hospitalizations with an accuracy of about 80 percent.</p><p>"This is really the first tool that I've been exposed to that gives me a sort of guestimate of what two weeks from now may look like," said Dr. <a href="https://www.northwell.edu/find-care/find-a-doctor/emergency-medicine/dr-eric-scott-cruzen-md-mba-11346068" target="_blank" rel="noopener noreferrer">Eric Cruzen, </a>chief medical informatics officer of Northwell's emergency medicine services and chair of the emergency department at Lenox Health Greenwich Village in Manhattan.</p><p>"Even if the data can provide an idea of whether to expect an increase, decrease, or stasis, that's valuable. Because every day we're working to estimate what tomorrow's going to bring. Any tool that's going to shed light on that is a good tool in my book."</p>
The value of forecasting
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTA0Njk2OC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYyMzM2NDQzOH0.rid9regiDaKczCCKBsu7wrHkNQ64Vz_XcOEZIzAhzgM/img.jpg?width=980" id="2bb93" class="rm-shortcode" data-rm-shortcode-id="31345afbdf2bd408fd3e9f31520c445a" data-rm-shortcode-name="rebelmouse-image" data-width="1546" data-height="1056" />Northwell emergency departments use the dashboard to monitor in real time.
Credit: Northwell Health
<p>One unique benefit of forecasting COVID-19 hospitalizations is that it allows health systems to better prepare, manage and allocate resources. For example, if the tool forecasted a surge in COVID-19 hospitalizations in two weeks, Northwell Health could begin:</p><ul><li>Making space for an influx of patients</li><li>Moving personal protective equipment to where it's most needed</li><li>Strategically allocating staff during the predicted surge</li><li>Increasing the number of tests offered to asymptomatic patients</li></ul><p>The health-care field is increasingly using machine learning. It's already helping doctors develop <a href="https://care.diabetesjournals.org/content/early/2020/06/09/dc19-1870" target="_blank">personalized care plans for diabetes patients</a>, improving cancer screening techniques, and enabling mental health professionals to better predict which patients are at <a href="https://healthitanalytics.com/news/ehr-data-fuels-accurate-predictive-analytics-for-suicide-risk" target="_blank" rel="noopener noreferrer">elevated risk of suicide</a>, to name a few applications.</p><p>Health systems around the world have already begun exploring how <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7315944/" target="_blank" rel="noopener noreferrer">machine learning can help battle the pandemic</a>, including better COVID-19 screening, diagnosis, contact tracing, and drug and vaccine development.</p><p>Cruzen said these kinds of tools represent a shift in how health systems can tackle a wide variety of problems.</p><p>"Health care has always used the past to predict the future, but not in this mathematical way," Cruzen said. "I think [Northwell Health's new predictive tool] really is a great first example of how we should be attacking a lot of things as we go forward."</p>Making machine-learning tools openly accessible
<p>Northwell Health has made its predictive tool <a href="https://github.com/northwell-health/covid-web-data-predictor" target="_blank">available for free</a> to any health system that wishes to utilize it.</p><p>"COVID is everybody's problem, and I think developing tools that can be used to help others is sort of why people go into health care," Dr. Cruzen said. "It was really consistent with our mission."</p><p>Open collaboration is something the world's governments and health systems should be striving for during the pandemic, said Michael Dowling, Northwell Health's president and CEO.</p><p>"Whenever you develop anything and somebody else gets it, they improve it and they continue to make it better," Dowling said. "As a country, we lack data. I believe very, very strongly that we should have been and should be now working with other countries, including China, including the European Union, including England and others to figure out how to develop a health surveillance system so you can anticipate way in advance when these things are going to occur."</p><p>In all, Northwell Health has treated more than 112,000 COVID patients. During the pandemic, Dowling said he's seen an outpouring of goodwill, collaboration, and sacrifice from the community and the tens of thousands of staff who work across Northwell.</p><p>"COVID has changed our perspective on everything—and not just those of us in health care, because it has disrupted everybody's life," Dowling said. "It has demonstrated the value of community, how we help one another."</p>
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What can Avicenna teach us about the mind-body problem?
The Persian polymath and philosopher of the Islamic Golden Age teaches us about self-awareness.
15 January, 2021
Photo by Andrew Spencer on Unsplash
Mind & Brain
Philosophers of the Islamic world enjoyed thought experiments.
<p>If the heavens vanished, they wondered, would time continue to pass? If existence were distinct from essence, would that mean that existence itself must exist? Can God turn your household servant into a horse, so that you come back home to find it has urinated all over your books?</p><p>But the most famous is the so-called 'flying man' thought experiment, devised by the most influential philosopher of the Islamic world, Avicenna (in Arabic, <em>Ibn Sīnā</em>, who lived from 980 to 1037 CE). Imagine, he says, that a person is created by God in mid-air, in good condition but with his sight veiled and his limbs outstretched so that he is touching nothing, not even his own body. This person has no memories, having only just been created. Will his mind be a blank, devoid as it is of past or present sensory experience? No, says Avicenna. He will be aware of his own existence.</p><p>Three questions immediately arise. First, when Douglas Adams, the author of <em>The Hitchhiker's Guide to the Galaxy</em> (1978), imagined a whale popping into existence in mid-air above an alien planet, had he been reading Avicenna? I have no idea, but I like to think so.</p><p>Second, is Avicenna right that the 'flying man' would be self-aware? Well, it's important to realise that Avicenna does not attempt to <em>argue</em> that the flying man would know that he exists. Rather, he takes it as obvious. In one version, he even tells readers that we should imagine ourselves being so created. If we put ourselves in the flying man's dangling shoes, we should just see that we would be self-aware. Indeed, this turns out to be a fundamental idea in Avicenna's philosophy. He thinks that we are all always self-aware, even when we're asleep or focusing hard on something other than ourselves. Paradoxically, we're often not <em>aware</em> of being self-aware: it is the non-interruptive background music of human psychology, something we notice only when our attention is called to it, a pre-reflective awareness of self. The flying man thought experiment is itself one way to call attention to this self-awareness: Avicenna calls it a <em>tanbīh</em>, meaning a 'pointer' to something.</p>
<p>Our self-awareness is a foundation for our first-person perspective on things. It's a sign of this that when I see, imagine or think something, I can immediately apprehend that I am seeing, imagining or thinking about that thing. Any other form of cognition – any awareness of other things – presupposes awareness of oneself.</p><p>Incidentally, you might object that the flying man would have certain forms of bodily awareness despite his lack of vision, hearing and so on. Wouldn't he at least sense the location of his limbs by another form of sensation, namely proprioception? Imagine you are in total darkness and your arm is not resting on anything: proprioception is the sense that tells you where it is. This is indeed a problem for the thought experiment as Avicenna sets it up, but it isn't really philosophically decisive. One can just modify the scenario by adding that God blocks the man's ability to use proprioception, or that the flying man's proprioceptive faculty happens to be defective. Avicenna's claim will then be that, even under these circumstances, the flying man would be aware of himself.</p><p>Now for the third, and hardest, question: what does the flying man thought experiment prove? Avicenna draws a surprising conclusion: it shows that we are not identical with our bodies. Just consider. The flying man is aware of himself; he knows that he exists. But he is not aware of his body; he doesn't know that his body exists, nor indeed that any body exists. And if I am aware of one thing but not another, how can those two things be identical?</p>
<p>This sounds pretty persuasive, until you reflect that one can be conscious of a thing without being conscious of everything about it. You, for example, have been aware of reading this article for the past few minutes, but you haven't been aware of reading something written while Dixieland jazz was playing. It would be a mistake to conclude from this that the article is not something written with Dixieland jazz playing. In fact, that is exactly what it is. To put it another way, the flying man could be aware of his self without realising that his self is a body. Contemporary philosophers would say that Avicenna is mistakenly moving from a 'transparent' to an 'opaque' context, which is basically a fancy way of saying what I just said.</p><p><a href="http://philpapers.org/rec/MARAFM" target="_blank">Efforts</a> have been made to spare Avicenna from this mistake. One possible way to rescue the argument would go like this. Avicenna is trying to criticise another way of thinking about the soul, one that goes back to Aristotle. According to the theory he rejects, the soul is so closely associated with the body that it can only be understood as an aspect or organising principle of the body, which Aristotle called the body's 'form'. The thought experiment is designed to show that this is wrong. It does so by calling to our attention that we have a means of access to our souls apart from bodily sensation, namely self-awareness.</p><p>How would this refute Aristotle? Well, consider again just why it is that the flying man is not aware of his body. It is because he is not currently using his senses and has never done so (he only just started existing, remember), and sense perception is, Avicenna assumes, the <em>only</em> way to become aware of any body. If this is right, then anything that the flying man grasps without using sense perception is not a body, not material. Since he does grasp his soul without using sense perception, his soul is therefore not a body.</p><p>On this reading, Avicenna would be helping himself to a pretty big assumption, which is that bodies can be discovered only by the senses. You can see, hear, touch, taste or smell them, but otherwise you can never so much as know that they exist. Since for Aristotle the soul was a form of the body, if you couldn't experience the body, you would not, on his account, have access to the soul; and yet, Avicenna claims, the falling man <em>would</em> have access to his soul.</p><p>I suspect this is (at least in part) what he had in mind in creating this thought experiment. But that's not to say that I'm convinced. All Avicenna has really done is to throw down a challenge to his materialist opponents: show me how a body could be aware of itself without using sensation to do so.</p><p><a href="https://global.oup.com/academic/product/philosophy-in-the-islamic-world-9780199577491?cc=au&lang=en&" rel="noopener noreferrer" target="_blank"><em>Philosophy in the Islamic World</em></a><em> by Peter Adamson is out now through Oxford University Press.</em><img src="https://metrics.aeon.co/count/99e82cab-61e0-4404-a510-3e190ab2802e.gif" alt="Aeon counter – do not remove"></p><p>Peter Adamson</p><p>This article was originally published at <a href="https://aeon.co/?utm_campaign=republished-article" target="_blank">Aeon</a> and has been republished under Creative Commons. Read the <a href="https://aeon.co/ideas/what-can-avicenna-teach-us-about-the-mind-body-problem" target="_blank">original article</a>.</p>
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The incredible physics behind quantum computing
Can computers do calculations in multiple universes? Scientists are working on it. Step into the world of quantum computing.
15 January, 2021
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- While today's computers—referred to as classical computers—continue to become more and more powerful, there is a ceiling to their advancement due to the physical limits of the materials used to make them. Quantum computing allows physicists and researchers to exponentially increase computation power, harnessing potential parallel realities to do so.
- Quantum computer chips are astoundingly small, about the size of a fingernail. Scientists have to not only build the computer itself but also the ultra-protected environment in which they operate. Total isolation is required to eliminate vibrations and other external influences on synchronized atoms; if the atoms become 'decoherent' the quantum computer cannot function.
- "You need to create a very quiet, clean, cold environment for these chips to work in," says quantum computing expert Vern Brownell. The coldest temperature possible in physics is -273.15 degrees C. The rooms required for quantum computing are -273.14 degrees C, which is 150 times colder than outer space. It is complex and mind-boggling work, but the potential for computation that harnesses the power of parallel universes is worth the chase.
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Octopus-like creatures inhabit Jupiter’s moon, claims space scientist
A leading British space scientist thinks there is life under the ice sheets of Europa.
03 May, 2020
Credit: NASA/JPL-Caltech/SETI Institute
Surprising Science
- A British scientist named Professor Monica Grady recently came out in support of extraterrestrial life on Europa.
- Europa, the sixth largest moon in the solar system, may have favorable conditions for life under its miles of ice.
- The moon is one of Jupiter's 79.
<p>Alien hunting is a hopeful activity and one reason behind our space programs that the public generally supports. Looking for other life is a strong incentive to be venturing out into space, despite having found none so far. A top British space scientist,<strong> Professor Monica Grady,</strong> gave all cosmic explorers a big dose of such hope in a recent speech. She is certain there's some form of life on Jupiter's moon, <strong>Europa</strong>.</p><p>This life would not look human, but more like an "octopus," and is likely residing in the cold waters under the moon's sheets of ice. </p><p>Grady, a Professor of Planetary and Space Science and Chancellor at Liverpool Hope University, thinks there's a great likelihood of undiscovered life somewhere in our galaxy.</p><p>She also supposes that the deeper caves and cavernous spaces of Mars could be harboring some subterranean creatures, likely bacteria, there to escape the solar radiation. They could be getting water from the ice buried deep down. </p><p style="margin-left: 20px;">"When it comes to the prospects of life beyond Earth, it's <strong>almost a racing certainty </strong>that there's life beneath the ice on Europa," <a href="https://phys.org/news/2020-02-certainty-life-europa-mars-uk.html" target="_blank">she said</a> in a February address.</p>
<p><span style="background-color: initial;">She thinks these life forms on Europa, </span><span style="background-color: initial;">390 million miles from Earth, could be higher in sophistication than the Martian bacteria, possibly having "the intelligence of an octopus."</span><br></p><p>Where would the creatures live on this moon of Jupiter? Somewhere below the very thick layer of ice, which goes 15 miles deep in some places. It's possible there is liquid water beneath all that ice, keeping whatever lives inside protected against radiation and the impact of asteroids and similar smashing bodies.</p><p><span></span><span style="background-color: initial;">The likelihood of life on Europa is bolstered by </span><span style="background-color: initial;">the possible <a href="https://ui.adsabs.harvard.edu/abs/2011AGUFM.P23D1743G/abstract" target="_blank">hydrothermal vents</a> on its ocean floor. Such vents are cradles of life on Earth.</span></p><p>Grady thinks that our solar system doesn't have to be particularly special and that statistically speaking, as we explore other stars and galaxies, we should be able to find conditions for life. "I think it's highly likely there will be life elsewhere—and I think it's highly likely they'll be made of the same elements," <a href="https://phys.org/news/2020-02-certainty-life-europa-mars-uk.html" target="_blank">stated</a> the professor.</p>
Neil deGrasse Tyson wants to go ice fishing on Europa
<div class="rm-shortcode" data-media_id="GLGsRX7e" data-player_id="FvQKszTI" data-rm-shortcode-id="f4790eb8f0515e036b24c4195299df28"> <div id="botr_GLGsRX7e_FvQKszTI_div" class="jwplayer-media" data-jwplayer-video-src="https://content.jwplatform.com/players/GLGsRX7e-FvQKszTI.js"> <img src="https://cdn.jwplayer.com/thumbs/GLGsRX7e-1920.jpg" class="jwplayer-media-preview" /> </div> <script src="https://content.jwplatform.com/players/GLGsRX7e-FvQKszTI.js"></script> </div><p>Grady did not want to guess whether we would contact extraterrestrials any time soon, citing the fact that distances between us and likely aliens might be gigantic. </p><p>On the other hand, she added, if you look at a grain of sand, you "can see that most of it is made up of silicates, but it's also got little patches of carbon in it—and that carbon is extra-terrestrial, because it also contains nitrogen and hydrogen, which is not a terrestrial signature."</p><p>This tiny sample, says Grady, shows it was hit by meteorites, asteroids, and interstellar dust, pointing out "It's giving us an idea of how complex the record of extra-terrestrial material really is."</p>
<p>As for Europa, it has certainly figured in conversations about alien life previously. As <a href="https://europa.nasa.gov/mission/why-europa/" target="_blank">NASA explains</a>, scientists call Europa an "ocean world" due to decades of observations that predict an ocean under its sheets of ice. </p><p><span style="background-color: initial;">In 2019, water vapor was confirmed there by NASA for the first time. While it might just have the right conditions for life, </span><span style="background-color: initial;">does this moon have little octopus E.T.s swimming about? Future studies will tell. </span></p>
Water Vapor Above Europa’s Surface Deteced for First Time
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The scent of sickness: 5 questions answered about using dogs – and mice and ferrets – to detect disease
Could medical detection animals smell coronavirus?
14 January, 2021
Leon Neal/Getty Images
Coronavirus
As COVID-19 continues to spread worldwide, scientists are analyzing new ways to track it.
<p> One promising approach is <a href="https://doi.org/10.1038/d41586-020-03149-9" target="_blank">training dogs to detect people who are infected</a> by smelling samples of human urine or sweat. Research scientist Glen Golden, who has trained dogs and ferrets to detect avian flu in birds, explains why certain animals are well suited to sniff out sickness.</p><h2>1. Which species have a nose for disease?</h2><p>Some animals have highly developed senses of smell. They include rodents; dogs and their wild relatives, like wolves and coyotes; and <a href="https://www.britannica.com/topic/list-of-mustelids-2058294" target="_blank">mustelids</a> – carnivorous mammals such as weasels, otters and ferrets. These species' brains have three or more times more functional olfactory receptor neurons – nerve cells that respond to odors – than species with less keen smelling abilities, including humans and other primates. </p><p>These neurons are responsible for detecting and identifying volatile olfactory compounds that send meaningful signals, like smoke from a fire or the aroma of fresh meat. A substance is volatile if it changes readily from liquid to gas at low temperatures, like the acetone that gives nail polish remover its fruity smell. Once it vaporizes, it can spread rapidly through the air.</p><p>When one of these animals detects a meaningful odor, the chemical signal is translated into messages and transported throughout its brain. The messages go simultaneously to the olfactory cortex, which is responsible for identifying, localizing and remembering odor, and to other brain regions responsible for decision-making and emotion. So these animals can detect many chemical signals over great distances and can make rapid and accurate mental associations about them. </p>
<h2>2. How do researchers choose a target scent?</h2><p>In most studies that have used dogs to detect cancer, the dogs have identified physical samples, such as skin, urine or breath, from patients who either have been diagnosed with cancer or have <a href="https://doi.org/10.1016/j.applanim.2004.04.008" target="_blank" rel="noopener noreferrer">undiagnosed cancer at an early stage</a>. Scientists don't know what odor cue the dogs use or whether it varies by type of cancer.</p><p>The U.S. Department of Agriculture's <a href="https://www.aphis.usda.gov/aphis/ourfocus/wildlifedamage/programs/nwrc" target="_blank" rel="noopener noreferrer">National Wildlife Research Center</a> in Colorado and the <a href="https://monell.org/" target="_blank" rel="noopener noreferrer">Monell Chemical Senses Center</a> in Pennsylvania have trained mice to detect <a href="https://doi.org/10.1371/journal.pone.0075411" target="_blank" rel="noopener noreferrer">avian influenza in fecal samples from infected ducks</a>. Bird flu is hard to detect in wild flocks, and it <a href="https://www.cdc.gov/flu/avianflu/avian-in-humans.htm" target="_blank" rel="noopener noreferrer">can spread to humans</a>, so this work is designed to help wildlife biologists monitor for outbreaks.</p><p>The Kimball lab at Monell taught the mice to get a reward when they smelled a confirmed positive sample from an infected animal. For example, mice would get a drink of water when they traveled down the arm of a Y-shaped maze that contained feces from a duck infected with avian influenza virus.</p><p>By chemically analyzing the fecal samples, researchers found that the concentration of volatile chemical compounds in them changed when a duck became infected with bird flu. So they inferred that this altered smell profile was what the mice recognized.</p><iframe src="https://www.youtube.com/embed/0UxLt3yugUA?wmode=transparent&start=0"></iframe><p>Members of the mustelid family, such as ferrets, badgers and otters, have highly developed senses of smell. Here a wolverine sniffs out frozen meat buried deep in the snow.</p><p>Building on that work, we've trained ferrets and dogs to detect avian influenza in fowl, such as wild ducks and domestic chickens, in a collaborative study between Colorado State University and the National Wildlife Research Center that is currently under review for publication.</p><p>With ferrets, we started by training them to alert, or signal that they had detected the target odor, by scratching on a box that contained high ratios of those volatile compounds and to ignore boxes that contained low ratios. Next we showed the ferrets fecal samples from both infected and noninfected ducks, and the ferrets immediately began alerting to the box containing the fecal sample from an infected duck.</p><p>This approach is similar to the way that dogs are trained to detect known volatile odors in explosives or illegal drugs. Sometimes, though, we have to let the detector animal determine the odor profile that it will respond to.</p>
<h2>3. Can animals be trained to detect more than one target?</h2><p>Yes. To avoid confusion about what a trained animal is detecting, we can teach it a different behavioral response for each target odor.</p><p>For example, the dogs in the U.S. Department of Agriculture's <a href="https://www.aphis.usda.gov/aphis/ourfocus/wildlifedamage/programs/nwrc/sa_spotlight/sniffing+out+disease" target="_blank" rel="noopener noreferrer">Wildlife Services Canine Disease Detection Program</a> respond with an aggressive alert, such as scratching, when they detect a sample from a duck infected with bird flu. When they detect a sample from a white-tailed deer infected by the prion that causes <a href="https://www.cdc.gov/prions/cwd/index.html" target="_blank" rel="noopener noreferrer">chronic wasting disease</a>, they respond with a passive alert such as sitting down.</p><p>Research at the University of Auburn has shown that dogs can remember and respond to <a href="https://doi.org/10.1007/s10071-020-01362-7" target="_blank" rel="noopener noreferrer">72 odors during an odor memory task</a>. The only limitation is how many ways a dog can communicate about different odor cues.</p>
<h2>4. What kinds of factors can complicate this process?</h2><p>First, any organization that trains animals to detect disease needs the right type of laboratory and equipment. Depending on the disease, that could include personal protection equipment and air filtering.</p><p>Another concern is whether the pathogen might infect the detection animals. If that's a risk, researchers may need to inactivate the samples before they expose the animals. Then they need to see whether that process has altered the volatiles that they are teaching the animals to associate with infection.</p><p>Finally, handlers have to think about how to reinforce the desired response from detection animals in the field. If they are working in a population of mostly noninfected people – for example, in an airport – and an animal doesn't get a chance to earn a reward, it may lose interest and stop working. We look for animals that have a strong drive to work without stopping, but working for a long time without reward can be challenging for even the most motivated animal.</p>
<h2>5. Why not build a machine that can do this?</h2><p>Right now we don't have devices that are as sensitive as animals with well-developed senses of smell. For example, a dog's sense of smell is <a href="https://doi.org/10.1016/j.applanim.2005.07.009" target="_blank" rel="noopener noreferrer">at least 1,000 times more sensitive than any mechanical device</a>. This could explain why dogs have detected cancer in tissue samples that have been <a href="https://doi.org/10.1016/j.applanim.2004.04.008" target="_blank" rel="noopener noreferrer">medically cleared as not cancerous</a></p><p>We also know that ferrets can detect avian flu infection in fecal samples before and after laboratory analysis shows that the virus has stopped shedding. This suggests that for some pathogens, there may be changes in volatiles in individuals who are infected but are asymptomatic.</p><p>As scientists learn more about how mammals' sense of smell works, they'll have a better chance of creating devices that are as sensitive and reliable in sniffing out disease.<img src="https://counter.theconversation.com/content/151832/count.gif?distributor=republish-lightbox-basic" alt="The Conversation"></p><p><a href="https://theconversation.com/profiles/glen-j-golden-1186384" target="_blank">Glen J. Golden</a>, Research Scientist/Scholar I, <em><a href="https://theconversation.com/institutions/colorado-state-university-1267" target="_blank" rel="noopener noreferrer">Colorado State University</a></em></p><p>This article is republished from <a href="https://theconversation.com/" target="_blank" rel="noopener noreferrer">The Conversation</a> under a Creative Commons license. Read the <a href="https://theconversation.com/the-scent-of-sickness-5-questions-answered-about-using-dogs-and-mice-and-ferrets-to-detect-disease-151832" target="_blank" rel="noopener noreferrer">original article</a>.</p>
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