John Cacioppo on Loneliness
John T. Cacioppo is the Tiffany and Margaret Blake Distinguished Service Professor at The University of Chicago, the Director of the University of Chicago Center for Cognitive and Social Neuroscience, and the Director of the Arete Initiative at the University of Chicago. He is the author of Loneliness: Human Nature and the Need for Social Connection.
Professor Cacioppo is a Big Think Delphi Fellow.
Cacioppo: Loneliness is the feeling that you’re socially isolated. It’s related to being physically isolated from other people, but it’s not the same thing. One can be lonely in a marriage, lonely in a family, they can be lonely in a crowd. So we found it isn’t the number of contacts or the frequency of interaction with other people, it’s the quality of those interactions. Freshmen who have gone to college find themselves among many, many other people, lots of social activities, they go to mixers, and they look around, everyone else is talking with other people and they’re sitting there, all alone in their head. And so, that actually can make their feeling of isolation greater for that moment. So, being around other people is not what makes people less lonely, it’s feeling connected to other people that makes them feel less lonely.
Question: How does loneliness differ from anxiety or depression?
Cacioppo: Traditionally, loneliness and depression, loneliness and anxiety were treated as very similar constructs, so much so that one of the common measures of depression that’s used in epidemiology has, as one of the questions, “Do you feel lonely?” Our own research and research of others have looked at whether loneliness and depression are the same thing and we find them to be separate constructs. They’re separate mental states. Our longitudinal research and our experimental research has shown that loneliness leads to increased depressive symptomatology. So, if… No matter how depressed you are today, if you’re feeling lonely today, you will be more depressed a year from now, above and beyond which our level of depression today would predict because of the loneliness. We also find that depression lead you to withdrawal, so a difference in depression and loneliness is loneliness makes you want to reach out and contact other people, be a part of that group, be a part of that relationship. Depression is associated with depressed affect but also with lethargy, kind of this withdrawal from others. And, indeed, with depression, we find, over time, people do withdraw from others and that withdrawal and in the increased stress associated with that leads them to feel lonelier. So, you have this pernicious feedback loop, the lonelier they are, the more depressed they’d become. The depressed they are, the more they withdraw and the lonelier they become. If you look at those two effects, though, the effect of loneliness and depression is stronger than the effect of depression on loneliness. People can be depressed for other reasons and feeling lonely, but many people who go in to seek treatment for depression, at the root of the problem is their feeling of disconnection and isolation, and unless that’s treated, the depression or any attempt to fix that is really just kind of a transient band aid. It’s not getting at the root problem.
Question: What are the symptoms of loneliness?
Cacioppo: The measurement of loneliness is somewhat not obvious. People know that they feel isolated. They feel disconnected. They don’t have others on whom they can rely or talk, but it’s mostly they don’t have a confidante. They don’t have anyone who affirms who they are. That’s part of it. Now, if you ask people do they feel lonely, there tends to be this stigma associated with loneliness, I think, or research has suggested that it’s inappropriate stigma, but there’s nevertheless this stigma associated with loneliness. So, people under report. If you ask them, “Do you feel lonely?” they under report. But if you ask them, are there others on whom they can rely, to whom they can relate and whom they can confide, that’s when you start to see people admitting this feeling of isolation. There’s also this sense in which they don’t have a collective identity. So, immediately after 9/11, when we all survived that tragedy, it made being an American salient. That’s a social identity. But, if you noticed, in this country, journalists were writing about the harmony, the goodwill that existed in America. That was a step up of what had been felt a week before 9/11. That’s part of being connected, and so, a lonely individual is also [absent at that] social identity and it may be in the form of feeling like you’re an American after a tragedy or [you might be a] Chicago Cubs or New York Yankee’s fan, these kinds of identity is a part of how we are connected to other individuals and other groups, and lonely individuals tend to lack those as well.
Question: How do we avoid being lonely?
Cacioppo: There are several secrets to overcoming or avoiding loneliness. I like to use the analog of hunger. Loneliness has evolved because it has a very adaptive purpose. We are fundamentally social species, but we need some signal when that important need isn’t being met, very much like hunger. We need a reasonable level of blood sugar, else we don’t have the metabolic resources, the energy to pursue foraging and other activities. When we start to have lower blood sugar levels, we become hungry, and that’s a signal that we should find food and eat and refuel. If we ignore that hunger signal, if we think that somehow that’s stigmatizing, and so we simply persist in not pursuing any food and ignoring that signal, we can become so depleted of energy that we’re no longer able to seek that food. So it can become chronic and deadly. Loneliness is very much like that, and instead of sustaining us with calories, it sustains us with connections. In evolutionary times, we were not able to fend off large, wild beasts very well, as individuals with a stick, nor were we able to take care of our offspring who have the longest period of abject dependency of any species, if we were simply solitary animals. We are able to achieve reproduction, survival and/or offspring survival long enough so that they too reproduce because we acted as a group, as a collective. So, finding yourself ostracized or separated from that group is a threatening, dangerous circumstance. Recognizing that you’re also going to understand how the feeling of loneliness, the pain of loneliness, the threat that’s associated with this loneliness is a signal, very much like hunger, but it’s there to cue the need to reconnect, to protect that part of our existence, and if we respond to it as that cue, then it can be very healthy. If you don’t respond to that cue, then you can fall into the grips of chronic loneliness, and that has, as I suggested, very deleterious mental, psychological effects, but also physiological effects.
John Cacioppo explains how loneliness differs from anxiety and depression.
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Are "humanized" pigs the future of medical research?
The U.S. Food and Drug Administration requires all new medicines to be tested in animals before use in people. Pigs make better medical research subjects than mice, because they are closer to humans in size, physiology and genetic makeup.
In recent years, our team at Iowa State University has found a way to make pigs an even closer stand-in for humans. We have successfully transferred components of the human immune system into pigs that lack a functional immune system. This breakthrough has the potential to accelerate medical research in many areas, including virus and vaccine research, as well as cancer and stem cell therapeutics.
Existing biomedical models
Severe Combined Immunodeficiency, or SCID, is a genetic condition that causes impaired development of the immune system. People can develop SCID, as dramatized in the 1976 movie “The Boy in the Plastic Bubble." Other animals can develop SCID, too, including mice.
Researchers in the 1980s recognized that SCID mice could be implanted with human immune cells for further study. Such mice are called “humanized" mice and have been optimized over the past 30 years to study many questions relevant to human health.
Mice are the most commonly used animal in biomedical research, but results from mice often do not translate well to human responses, thanks to differences in metabolism, size and divergent cell functions compared with people.
Nonhuman primates are also used for medical research and are certainly closer stand-ins for humans. But using them for this purpose raises numerous ethical considerations. With these concerns in mind, the National Institutes of Health retired most of its chimpanzees from biomedical research in 2013.
Alternative animal models are in demand.
Swine are a viable option for medical research because of their similarities to humans. And with their widespread commercial use, pigs are met with fewer ethical dilemmas than primates. Upwards of 100 million hogs are slaughtered each year for food in the U.S.
In 2012, groups at Iowa State University and Kansas State University, including Jack Dekkers, an expert in animal breeding and genetics, and Raymond Rowland, a specialist in animal diseases, serendipitously discovered a naturally occurring genetic mutation in pigs that caused SCID. We wondered if we could develop these pigs to create a new biomedical model.
Our group has worked for nearly a decade developing and optimizing SCID pigs for applications in biomedical research. In 2018, we achieved a twofold milestone when working with animal physiologist Jason Ross and his lab. Together we developed a more immunocompromised pig than the original SCID pig – and successfully humanized it, by transferring cultured human immune stem cells into the livers of developing piglets.
During early fetal development, immune cells develop within the liver, providing an opportunity to introduce human cells. We inject human immune stem cells into fetal pig livers using ultrasound imaging as a guide. As the pig fetus develops, the injected human immune stem cells begin to differentiate – or change into other kinds of cells – and spread through the pig's body. Once SCID piglets are born, we can detect human immune cells in their blood, liver, spleen and thymus gland. This humanization is what makes them so valuable for testing new medical treatments.
We have found that human ovarian tumors survive and grow in SCID pigs, giving us an opportunity to study ovarian cancer in a new way. Similarly, because human skin survives on SCID pigs, scientists may be able to develop new treatments for skin burns. Other research possibilities are numerous.
The ultraclean SCID pig biocontainment facility in Ames, Iowa. Adeline Boettcher, CC BY-SA
Pigs in a bubble
Since our pigs lack essential components of their immune system, they are extremely susceptible to infection and require special housing to help reduce exposure to pathogens.
SCID pigs are raised in bubble biocontainment facilities. Positive pressure rooms, which maintain a higher air pressure than the surrounding environment to keep pathogens out, are coupled with highly filtered air and water. All personnel are required to wear full personal protective equipment. We typically have anywhere from two to 15 SCID pigs and breeding animals at a given time. (Our breeding animals do not have SCID, but they are genetic carriers of the mutation, so their offspring may have SCID.)
As with any animal research, ethical considerations are always front and center. All our protocols are approved by Iowa State University's Institutional Animal Care and Use Committee and are in accordance with The National Institutes of Health's Guide for the Care and Use of Laboratory Animals.
Every day, twice a day, our pigs are checked by expert caretakers who monitor their health status and provide engagement. We have veterinarians on call. If any pigs fall ill, and drug or antibiotic intervention does not improve their condition, the animals are humanely euthanized.
Our goal is to continue optimizing our humanized SCID pigs so they can be more readily available for stem cell therapy testing, as well as research in other areas, including cancer. We hope the development of the SCID pig model will pave the way for advancements in therapeutic testing, with the long-term goal of improving human patient outcomes.
Adeline Boettcher earned her research-based Ph.D. working on the SCID project in 2019.
Satellite imagery can help better predict volcanic eruptions by monitoring changes in surface temperature near volcanoes.
- A recent study used data collected by NASA satellites to conduct a statistical analysis of surface temperatures near volcanoes that erupted from 2002 to 2019.
- The results showed that surface temperatures near volcanoes gradually increased in the months and years prior to eruptions.
- The method was able to detect potential eruptions that were not anticipated by other volcano monitoring methods, such as eruptions in Japan in 2014 and Chile in 2015.
How can modern technology help warn us of impending volcanic eruptions?
One promising answer may lie in satellite imagery. In a recent study published in Nature Geoscience, researchers used infrared data collected by NASA satellites to study the conditions near volcanoes in the months and years before they erupted.
The results revealed a pattern: Prior to eruptions, an unusually large amount of heat had been escaping through soil near volcanoes. This diffusion of subterranean heat — which is a byproduct of "large-scale thermal unrest" — could potentially represent a warning sign of future eruptions.
Conceptual model of large-scale thermal unrestCredit: Girona et al.
For the study, the researchers conducted a statistical analysis of changes in surface temperature near volcanoes, using data collected over 16.5 years by NASA's Terra and Aqua satellites. The results showed that eruptions tended to occur around the time when surface temperatures near the volcanoes peaked.
Eruptions were preceded by "subtle but significant long-term (years), large-scale (tens of square kilometres) increases in their radiant heat flux (up to ~1 °C in median radiant temperature)," the researchers wrote. After eruptions, surface temperatures reliably decreased, though the cool-down period took longer for bigger eruptions.
"Volcanoes can experience thermal unrest for several years before eruption," the researchers wrote. "This thermal unrest is dominated by a large-scale phenomenon operating over extensive areas of volcanic edifices, can be an early indicator of volcanic reactivation, can increase prior to different types of eruption and can be tracked through a statistical analysis of little-processed (that is, radiance or radiant temperature) satellite-based remote sensing data with high temporal resolution."
Temporal variations of target volcanoesCredit: Girona et al.
Although using satellites to monitor thermal unrest wouldn't enable scientists to make hyper-specific eruption predictions (like predicting the exact day), it could significantly improve prediction efforts. Seismologists and volcanologists currently use a range of techniques to forecast eruptions, including monitoring for gas emissions, ground deformation, and changes to nearby water channels, to name a few.
Still, none of these techniques have proven completely reliable, both because of the science and the practical barriers (e.g. funding) standing in the way of large-scale monitoring. In 2014, for example, Japan's Mount Ontake suddenly erupted, killing 63 people. It was the nation's deadliest eruption in nearly a century.
In the study, the researchers found that surface temperatures near Mount Ontake had been increasing in the two years prior to the eruption. To date, no other monitoring method has detected "well-defined" warning signs for the 2014 disaster, the researchers noted.
The researchers hope satellite-based infrared monitoring techniques, combined with existing methods, can improve prediction efforts for volcanic eruptions. Volcanic eruptions have killed about 2,000 people since 2000.
"Our findings can open new horizons to better constrain magma–hydrothermal interaction processes, especially when integrated with other datasets, allowing us to explore the thermal budget of volcanoes and anticipate eruptions that are very difficult to forecast through other geophysical/geochemical methods."
Certain water beetles can escape from frogs after being consumed.
- A Japanese scientist shows that some beetles can wiggle out of frog's butts after being eaten whole.
- The research suggests the beetle can get out in as little as 7 minutes.
- Most of the beetles swallowed in the experiment survived with no complications after being excreted.
In what is perhaps one of the weirdest experiments ever that comes from the category of "why did anyone need to know this?" scientists have proven that the Regimbartia attenuata beetle can climb out of a frog's butt after being eaten.
The research was carried out by Kobe University ecologist Shinji Sugiura. His team found that the majority of beetles swallowed by black-spotted pond frogs (Pelophylax nigromaculatus) used in their experiment managed to escape about 6 hours after and were perfectly fine.
"Here, I report active escape of the aquatic beetle R. attenuata from the vents of five frog species via the digestive tract," writes Sugiura in a new paper, adding "although adult beetles were easily eaten by frogs, 90 percent of swallowed beetles were excreted within six hours after being eaten and, surprisingly, were still alive."
One bug even got out in as little as 7 minutes.
Sugiura also tried putting wax on the legs of some of the beetles, preventing them from moving. These ones were not able to make it out alive, taking from 38 to 150 hours to be digested.
Naturally, as anyone would upon encountering such a story, you're wondering where's the video. Thankfully, the scientists recorded the proceedings:
The Regimbartia attenuata beetle can be found in the tropics, especially as pests in fish hatcheries. It's not the only kind of creature that can survive being swallowed. A recent study showed that snake eels are able to burrow out of the stomachs of fish using their sharp tails, only to become stuck, die, and be mummified in the gut cavity. Scientists are calling the beetle's ability the first documented "active prey escape." Usually, such travelers through the digestive tract have particular adaptations that make it possible for them to withstand extreme pH and lack of oxygen. The researchers think the beetle's trick is in inducing the frog to open a so-called "vent" controlled by the sphincter muscle.
"Individuals were always excreted head first from the frog vent, suggesting that R. attenuata stimulates the hind gut, urging the frog to defecate," explains Sugiura.
For more information, check out the study published in Current Biology.
The design of a classic video game yields insights on how to address global poverty.
- A new essay compares the power-up system in Mario Kart to feedback loops in real-life systems.
- Both try to provide targeted benefits to those who most need them.
- While games are simpler than reality, Mario's example makes the real-life cases easier to understand.
Poverty can be a self-sustaining cycle that might require an external influence to break it. A new paper published in Nature Sustainability and written by professor Andrew Bell of Boston University suggests that we could improve global anti-poverty and economic development systems by turning to an idea in a video game about a race car-driving Italian plumber.
A primer on Mario Kart
For those who have not played it, Mario Kart is a racing game starring Super Mario and other characters from the video game franchise that bears his name. Players race around tracks collecting power-ups that can directly help them, such as mushrooms that speed up their karts, or slow down other players, such as heat-seeking turtle shells that momentarily crash other karts.
The game is well known for having a mechanism known as "rubber-banding." Racers in the front of the pack get wimpy power-ups, like banana peels to slip up other karts, while those toward the back get stronger ones, like golden mushrooms that provide extra long speed boosts. The effect of this is that those in the back are pushed towards the center, and those in front don't get any boosts that would make catching them impossible.
If you're in last, you might get the help you need to make a last-minute break for the lead. If you're in first, you have to be on the lookout for these breakouts (and the ever-dreaded blue shells). The game remains competitive and fun.
Rubber-banding: A moral and economic lesson from Mario Kart
In the real world, we see rubber-banding used all the time. Welfare systems tend to provide more aid to those who need it than those who do not. Many of them are financed by progressive taxation, which is heavier on the well-off than the down-and-out. Some research suggests that these do work, as countries with lower levels of income inequality have higher social mobility levels.
It is a little more difficult to use rubber-banding in real life than in a video game, of course. While in the game, it is easy to decide who is doing well and who is not, things can be a little more muddled in reality. Furthermore, while those in a racing game are necessarily antagonistic to each other, real systems often strive to improve conditions for everybody or to reach common goals.
As Bell points out, rubber-banding can also be used to encourage sustainable, growth programs that help the poor other than welfare. They point out projects such as irrigation systems in Pakistan or Payments for Ecosystems Services (PES) schemes in Malawi, which utilize positive feedback loops to both provide aid to the poor and promote stable systems that benefit everyone.
Rubber-banding feedback loops in different systems. Mario Kart (a), irrigation systems in Pakistan (b), and PES operations in Malawi (c) are shown. Links between one better-off (blue) and one worse-off (red) individual are highlighted. Feedback in Mario Kart (a), designed to balance the racers, imprAndrew Bell/ Nature Sustainability
In the Malawi case, farmers were paid to practice conservation agriculture to reduce the amount of sediment from their farms flowing into a river. This immediately benefits hydroelectric producers and their customers but also provides real benefits to farmers in the long run as their soil doesn't erode. By providing an incentive to the farmers to conserve the soil, a virtuous cycle of conservation, soil improvement, and improved yields can begin.
While this loop differs from the rubber-banding in Mario, the game's approach can help illustrate the benefits of rubber-banding in achieving a more equitable world.
The task now, as Bell says in his paper, is to look at problems that exist and find out "what the golden mushroom might be."