Thursday, 14 November 2013

Probiotics for depression

Nov. 14, 2013 — Probiotics are not new, but their status as a nutritional buzzword is. Most folks have now heard and seen the term countless times in commercials and advertisements, as yogurt, dietary supplement, natural food product, and even cosmetic companies promote their probiotic-containing products.

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But what are they, and why are they important? Probiotics are live bacteria that help maintain a healthy digestive system. The development and marketing of products that contain live bacteria has flourished as there is a growing perceived interest in the ingestion of 'natural foods' that might promote health.
Many of the numerous health-improvement claims have yet to be supported scientifically, but these micro-organisms do exert positive effects in intestinal tracts, particularly when used to counteract the effects of antibiotics, which kill both 'bad' and 'good' bacteria. Indeed, the first known description of probiotics occurred in 1908 when a Russian scientist named Élie Metchnikoff observed that rural Europeans who regularly consumed fermented milk product had longer life spans.
Over the past few years, studies have been undertaken to explore the possible impact of probiotics on behavior. It is within this context that the concept of a psychobiotic has arisen.
The authors of a new review article in Biological Psychiatry,Timothy Dinan and his colleagues from University College Cork in Ireland, define a psychobiotic as "a live organism that, when ingested in adequate amounts, produces a health benefit in patients suffering from psychiatric illness."
They review the evidence that these bacteria, when ingested in adequate amounts, offer enormous potential for the treatment of depression and other stress-related disorders.
The gut microbiota, which contains approximately 1 kg of bacteria, can be modulated by diet and many other factors. It is not static and can change from day to day, starting at birth. Evidence has shown that even the form of delivery (vaginal versus cesarean) alters an individual's microbiota.
Early life stress, such as maternal separation, is known to induce long-term changes in the microbiome. Dinan and his colleagues review one study that assessed the potential benefits of a specific probiotic, B. infantis, in rats displaying depressive behavior due to maternal separation. The probiotic treatment normalized both their behavior and their previously-abnormal immune response. This preclinical study and others like it strongly support the hypothesis that probiotics have the potential to exert behavioral and immunological effects.
Some psychobiotics have been shown to have anti-inflammatory effects. This is important because depression and stress are both associated with inflammation in the body. Infectious diseases, such as syphilis and Lyme disease, can also produce depressive states. Evidence suggests that immune activations, perhaps via psychobiotic action, could alleviate such states. According to the authors, "the intestinal microbial balance may alter the regulation of inflammatory responses and in so doing, may be involved in the modulation of mood and behavior."
Human studies are still largely lacking, but a few have shown promising results. In one, healthy volunteers received either a probiotic combination (L.. helveticus R0052 and B. longum) or placebo for 30 days. Those who received the probiotics reported lower stress levels. In a separate study, volunteers who consumed a yogurt containing probiotics reported improved mood.
"What is clear at this point is that, of the large number of putative probiotics, only a small percentage have an impact on behaviour and may qualify as psychobiotics," said Dinan.
"This intriguing new area of research may open new possibilities for the treatment of depression," said Dr. John Krystal, Editor of Biological Psychiatry.
For now, we must all wait for scientists to conduct large-scale, placebo-controlled trials to provide definitive evidence.

Wednesday, 16 October 2013

Will Power Alone Is Not Enough

Oct. 15, 2013 — In an ideal world, employees would totally identify with their company's business objectives, be experts in their field and extremely motivated about their work. But in reality, this is not always the case and this places the spotlight on motivational skills for anyone in a leadership position.

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"There are three components to motivation. The first is our conscious objectives and desires -- for example, the aspiration for a highly paid role in a company in order to achieve a certain standard of living. We are also driven by unconscious, implicit motives. These are deeply rooted in our emotions and can include the desire to do things well, have an impact on and control over others, and engage in interpersonal relationships," explains Prof. Hugo Kehr from the Chair of Psychology at Technische Universität München (TUM). "The third motivational component builds on the skills and capabilities that we bring to a role."
When all three components dovetail, we are highly motivated, focused and happy in our work. But if one component is missing, willpower can help bridge the gap. However, sheer willpower or self-control won't keep us going for long. Together with TUM sports psychologist, Dr. Peter Gröpel, Prof. Kehr investigated how our unconscious motivation can influence our willpower.
Ice Age puts willpower to the test
To research the effect of the unconscious motives, the researchers gave their subjects a task that required them to overcome a certain challenge. They then looked at how much willpower they had left for a second challenge. The hypothesis was based on the assumption that the stronger the level of unconscious motivation, the longer the self-control would prevail.
In the first part of the study, subjects were shown a key scene from the movie Dead Poets Society, in which an overbearing father emphatically forbids his son from being an actor. One group of participants was asked to reenact the scene, taking on the role of the father. The control group simply had to write down the dialogue.
In the second part of the experiment, the experimenter showed the participants one of the funniest scenes from the animated film Ice Age and asked them not to smile or laugh. "Subjects had to use their willpower in both situations: In the first part, to play an unpleasant character in front of a video camera, and in the second, to suppress the desire to laugh," says Gröpel.
The power of unconscious motivation
Using standard tests, the psychologists had already assessed the strength of the participants' drive for power (their inner motivation to influence and control others). The idea was that strong power motivation might assist them in the task of playing the domineering father.
Indeed, they discovered that participants with a stronger power motive found it easier not to laugh during the Ice Age scene. Prof. Kehr explains: "We can conclude from this that they were able to draw on their internal motivation while completing the first task -- and so they had more willpower left for the second task." This difference was not observed in the control group, who only had to retell the story of the conflict.
In a similar experiment, the researchers looked at another motive: the motivation to do things well and achieve some standard of excellence. "Again, it was clear that those with a strong achievement motivation did not drain their willpower resources and so performed better overall," says Dr. Gröpel.
Setting these findings within an occupational context, the researchers recommend increasing internal motivation through targeted incentives. Employees would thus need less energy to master challenges -- and reveal higher levels of motivation with subsequent tasks or challenges. Prof. Kehr gives some examples: "An individual who is motivated by power could be endowed with a team-leading position in the company. And an employee who is motivated by achievement can be best encouraged through creative projects with little bureaucratic red tape."
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Sunday, 13 October 2013

increasing intelligence

1. Seek Novelty
It is no coincidence that geniuses like Einstein were skilled in multiple areas, or polymaths, as we like to refer to them. Geniuses are constantly seeking out novel activities, learning a new domain. It’s their personality.
There is only one trait out of the "Big Five" from the Five Factor Model of personality (Acronym: OCEAN, or Openness, Conscientiousness, Extroversion, Agreeableness, and Neuroticism) that correlates with IQ, and it is the trait of Openness to new experience. People who rate high on Openness are constantly seeking new information, new activities to engage in, new things to learn—new experiences in general [2].
When you seek novelty, several things are going on. First of all, you are creating new synaptic connections with every new activity you engage in. These connections build on each other, increasing your neural activity, creating more connections to build on other connections—learning is taking place.
An area of interest in recent research [pdf] is neural plasticity as a factor in individual differences in intelligence. Plasticity is referring to the number of connections made between neurons, how that affects subsequent connections, and how long-lasting those connections are. Basically, it means how much new information you are able to take in, and if you are able to retain it, making lasting changes to your brain. Constantly exposing yourself to new things helps puts your brain in a primed state for learning.
Novelty also triggers dopamine (I have mentioned this before in other posts), which not only kicks motivation into high gear, but it stimulates neurogenesis—the creation of new neurons—and prepares your brain for learning. All you need to do is feed the hunger.
Excellent learning condition = Novel Activity—>triggers dopamine—>creates a higher motivational state—>which fuels engagement and primes neurons—>neurogenesis can take place + increase in synaptic plasticity(increase in new neural connections, or learning).
As a follow-up of the Jaeggi study, researchers in Sweden [pdf] found that after 14 hours of training working memory over 5 weeks’ time, there was an increase ofdopamine D1 binding potential in the prefrontal and parietal areas of the brain. This particular dopamine receptor, the D1 type, is associated with neural growth and development, among other things. This increase in plasticity, allowing greater binding of this receptor, is a very good thing for maximizing cognitive functioning.
Take home point: Be an "Einstein". Always look to new activities to engage your mind—expand your cognitive horizons. Learn an instrument. Take an art class. Go to a museum. Read about a new area of science. Be a knowledge junkie.
2. Challenge Yourself
There are absolutely oodles of terrible things written and promoted on how to "train your brain" to "get smarter". When I speak of "brain training games", I’m referring to the memorization and fluency-type games, intended to increase your speed of processing, etc, such as Sudoku, that they tell you to do in your "idle time" (complete oxymoron, regarding increasing cognition). I’m going to shatter some of that stuff you’ve previously heard about brain training games. Here goes: They don’t work. Individual brain training games don’t make you smarter—they make you more proficient at the brain training games.
Now, they do serve a purpose, but it is short-lived. The key to getting something out of those types of cognitive activities sort of relates to the first principle of seeking novelty. Once you master one of those cognitive activities in the brain-training game,you need to move on to the next challenging activity. Figure out how to play Sudoku? Great! Now move along to the next type of challenging game. There is research that supports this logic.
A few years ago, scientist Richard Haier wanted to see if you could increase your cognitive ability by intensely training on novel mental activities for a period of several weeks. They used the video game Tetris as the novel activity, and used people who had never played the game before as subjects (I know—can you believe they exist?!). What they found, was that after training for several weeks on the game Tetris, the subjects experienced an increase in cortical thickness, as well as an increase in cortical activity, as evidenced by the increase in how much glucose was used in that area of the brain. Basically, the brain used more energy during those training times, and bulked up in thickness—which means more neural connections, or new learned expertise—after this intense training. And they became experts at Tetris. Cool, right?
Here’s the thing: After that initial explosion of cognitive growth, they noticed adecline in both cortical thickness, as well as the amount of glucose used during that task. However, they remained just as good at Tetris; their skill did not decrease. The brain scans showed less brain activity during the game-playing, instead of more, as in the previous days. Why the drop? Their brains got more efficient. Once their brain figured out how to play Tetris, and got really good at it, it got lazy. It didn’t need to work as hard in order to play the game well, so the cognitive energy and the glucose went somewhere else instead.
Efficiency is not your friend when it comes to cognitive growth. In order to keep your brain making new connections and keeping them active, you need to keep moving on to another challenging activity as soon as you reach the point of masteryin the one you are engaging in. You want to be in a constant state of slight discomfort, struggling to barely achieve whatever it is you are trying to do, as Einstein alluded to in his quote. This keeps your brain on its toes, so to speak. We’ll come back to this point later on.
3. Think Creatively
When I say thinking creatively will help you achieve neural growth, I am not talking about painting a picture, or doing something artsy, like we discussed in the first principle,Seeking Novelty. When I speak of creative thinking, I am talking about creative cognition itself, and what that means as far as the process going on in your brain.
Contrary to popular belief, creative thinking does not equal "thinking with the right side of your brain". It involves recruitment from both halves of your brain, not just the right. Creative cognition involves divergent thinking (a wide range of topics/subjects), making remote associations between ideas, switching back and forth between conventional and unconventional thinking (cognitive flexibility), and generating original, novel ideas that are also appropriate to the activity you are doing. In order to do this well, you need both right and left hemispheres working in conjunction with each other.
Several years ago, Dr Robert Sternberg, former Dean at Tufts University, opened thePACE (Psychology of Abilities, Competencies, and Expertise) Center, in Boston. Sternberg has been on a quest to not only understand the fundamental concept of intelligence, but also to find ways in which any one person can maximize his or her intelligence through training, and especially, through teaching in schools.
Here Sternberg describes the goals of the PACE Center, which was started at Yale:
"The basic idea of the center is that abilities are not fixed but rather flexible, that they’re modifiable, and that anyone can transform their abilities into competencies, and their competencies into expertise," Sternberg explains. "We’re especially interested in how we can help people essentially modify their abilities so that they can be better able to face the tasks and situations they’re going to confront in life."
As part of a research study, The Rainbow Project [pdf], he created not only innovative methods of creative teaching in the classroom, but generated assessment procedures that tested the students in ways that got them to think about the problems in creative and practical ways, as well as analytical, instead of just memorizing facts.
Sternberg explains,
"In the Rainbow Project we created assessments of creative and practical as well as analytical abilities. A creative test might be: ‘Here’s a cartoon. Caption it.’ A practical problem might be a movie of a student going into a party, looking around, not knowing anyone, and obviously feeling uncomfortable. What should the student do?"
He wanted to find out if by teaching students to think creatively (and practically)about a problem, as well as for memory, he could get them to (i) Learn more about the topic, (ii) Have more fun learning, and (iii) Transfer that knowledge gained to other areas of academic performance. He wanted to see if by varying the teaching and assessment methods, he could prevent "teaching to the test" and get the students to actually learn more in general. He collected data on this, and boy, did he get great results.
In a nutshell? On average, the students in the test group (the ones taught using creative methods) received higher final grades in the college course than the control group (taught with traditional methods and assessments). But—just to make things fair— he also gave the test group the very same analytical-type exam that the regular students got (a multiple choice test), and they scored higher on that test as well. That means they were able to transfer the knowledge they gained using creative, multimodal teaching methods, and score higher on a completely different cognitive test of achievement on that same material. Sound familiar?
4. Do Things the Hard Way
I mentioned earlier that efficiency is not your friend if you are trying to increase your intelligence. Unfortunately, many things in life are centered on trying to make everything more efficient. This is so we can do more things, in a shorter amount of time, expending the least amount of physical and mental energy possible. However, this isn’t doing your brain any favors.
Take one object of modern convenience, GPS. GPS is an amazing invention. I am one of those people GPS was invented for. My sense of direction is terrible. I get lost all the time. So when GPS came along, I was thanking my lucky stars. But you know what? After using GPS for a short time, I found that my sense of direction was worse. If I failed to have it with me, I was even more lost than before. So when I moved to Boston—the city that horror movies and nightmares about getting lost are modeled after—I stopped using GPS.
I won’t lie—it was painful as hell. I had a new job which involved traveling all over the burbs of Boston, and I got lost every single day for at least 4 weeks. I got lost so much, I thought I was going to lose my job due to chronic lateness (I even got written up for it). But—in time, I started learning my way around, due to the sheer amount of practice I was getting at navigation using only my brain and a map. I began toactually get a sense of where things in Boston were, using logic and memory, not GPS. I can still remember how proud I was the day a friend was in town visiting, and I was able to effectively find his hotel downtown with only a name and a location description to go on—not even an address. It was like I had graduated from navigational awareness school.
Technology does a lot to make things in life easier, faster, more efficient, but sometimes our cognitive skills can suffer as a result of these shortcuts, and hurt us in the long run. Now, before everyone starts screaming and emailing my transhumanist friends to say that I’ve sinned by trashing tech—that’s not what I’m doing.
Look at it this way: Driving to work takes less physical energy, saves time, and it’s probably more convenient and pleasant than walking. Not a big deal. But if you drove everywhere you went, or spent your life on a Segway, even to go very short distances, you aren’t going to be expending any physical energy. Over time, your muscles will atrophy, your physical state will weaken, and you’ll probably gain weight. Your overall health will probably decline as a result.
Your brain needs exercise as well. If you stop using your problem-solving skills, your spatial skills, your logical skills, your cognitive skills—how do you expect your brain to stay in top shape—never mind improve? Think about modern conveniences that are helpful, but when relied on too much, can hurt your skill in that domain. Translation software: amazing, but my multilingual skills have declined since I started using it more. I’ve now forced myself to struggle through translations before I look up the correct format. Same goes for spell-check and autocorrect. In fact, I think autocorrect was one of the worst things ever invented for the advancement of cognition. You know the computer will catch your mistakes, so you plug along, not even thinking about how to spell any more. As a result of years of relying on autocorrect and spell-check, as a nation, are we worse spellers? (I would love someone to do a study on this.)
There are times when using technology is warranted and necessary. But there are times when it’s better to say no to shortcuts and use your brain, as long as you can afford the luxury of time and energy. Walking to work every so often or taking the stairs instead of the elevator a few times a week is recommended to stay in good physical shape. Don’t you want your brain to be fit as well? Lay off the GPS once in a while, and do your spatial and problem-solving skills a favor. Keep it handy, but try navigating naked first. Your brain will thank you.
5. Network
And that brings us to the last element to maximize your cognitive potential: Networking. What’s great about this last objective is that if you are doing the other four things, you are probably already doing this as well. If not, start. Immediately.
By networking with other people—either through social media such as Facebook or Twitter, or in face-to-face interactions—you are exposing yourself to the kinds of situations that are going to make objectives 1-4 much easier to achieve. By exposing yourself to new people, ideas, and environments, you are opening yourself up to new opportunities for cognitive growth. Being in the presence of other people who may be outside of your immediate field gives you opportunities to see problems from a new perspective, or offer insight in ways that you had never thought of before. Learning is all about exposing yourself to new things and taking in that information in ways that are meaningful and unique—networking with other people is a great way to make that happen. I’m not even going to get into the social benefits and emotional well-being that is derived from networking as a factor here, but that is just an added perk.
Steven Johnson, author who wrote the book "Where Good Ideas Come From", discusses the importance of groups and networks for the advancement of ideas. If you are looking for ways to seek out novel situations, ideas, environments, and perspectives, then networking is the answer. It would be pretty tough to implement this "Get Smarter" regiment without making networking a primary component. Greatest thing about networking: Everyone involved benefits. Collective intelligence for the win!
And I have one more thing to mention…
Remember back to the beginning of this article where I told the story about my clients with autism spectrum disorders? Let’s think about that for a moment, in light of everything else we discussed about how to increase your fluid intelligence. Why were those children able to achieve at such a high level? It was not by chance or miracle—it was because we incorporated all of these learning principles into their therapy program. While most other therapy providers were stuck in the "Errorless Learning" paradigm and barely-modified "Lovaas Techniques" of Applied Behavior Analysis, we adopted and fully embraced a multimodal approach to teaching. We made the kids struggle to learn, we used the most creative ways we could think of, and we challenged them beyond what they seemed capable of—we set the bar very high. But you know what? They surpassed that bar time and time again, and made me truly believe that amazing things are possible if you have enough will and courage and perseverance to set yourself on that path and stick with it. If those kids with disabilities can live this lifestyle of constantly maximizing their cognitive potential, then so can you.
And I have a departing question for you to ponder as well: If we have all of this supporting data, showing that these teaching methods and ways of approaching learning can have such a profound positive effect on cognitive growth, why aren’t more therapy programs or school systems adopting some of these techniques? I’d love to see this as the standard in teaching, not the exception. Let’s try something novel and shake up the education system a little bit, shall we? We’d raise the collective IQ something fierce.
Intelligence isn’t just about how many levels of math courses you’ve taken, how fast you can solve an algorithm, or how many vocabulary words you know that are over 6 characters. It’s about being able to approach a new problem, recognize its important components, and solve it—then take that knowledge gained and put it towards solving the next, more complex problem. It’s about innovation and imagination, and about being able to put that to use to make the world a better place. This is the kind of intelligence that is valuable, and this is the type of intelligence we should be striving for and encouraging.
This article is adapted from a presentation I gave at the Humanity + Summit at Harvard University in June 2010.
[1.] The dual n-back test, while lumped into the "brain training" genre, is not your typical brain training game. It is specific and complicated, uses multiple modes of stimuli, and not the type I’m referring to when I say "brain training games".
[2.] "Openness" or novelty-seeking is not the same as thrill-seeking behavior. The motivation for the former is driven by dopamine, and associated with curiosity—the latter by adrenaline, and typically associated with more dangerous activities.
Works Cited:
Haier, R. E. (2007). The Parieto-Frontal Integration Theory (P-FIT) of Intelligence: Converging Neuroinaging EvidenceBehavioral and Brain Sciences, 135-187.
Haier, R. J. (1993). Cerebral glucose metabolism and intelligence. In P. A. Vernon,Biological approaches to the study of human intelligence (pp. 317-373). Norwood, N. J.: Ablex.
Susanne M. Jaeggi, M. B. (2008). Improving Fluid intelligence With Training on Working MemoryProceedings of the National Academy of Sciences. doi: 10.1073/pnas.0801268105
Ramey, C. T. (1998). Early Intervention and Early ExperienceAmerican Psychologist, 109-120.
Sternberg, R. (2008). Increasing Fluid Intelligence is Possible After All. PNAS, 105, no. 19 , 6791- 6792.
Sternberg, R. J. (1985). Implicit Theories of Intelligence, Creativity, and Wisdom.Journal of Personality and Social Psychology, 49 , 607-627.
Sternberg, R. J. (1999). The Theory of Sucessful IntelligenceReview of General Psychology, 3 , 292-316.
Weinberg, R. (1989). Intelligence and IQAmerican Psychologist, 98-104.
Image Credits: Andrea Kuszewski

Friday, 23 August 2013

Anxiety pathway discovered

Brain circuit that controls anxiety levels discovered

Research could help find better drugs to treat anxiety.
August 23, 2013
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The tips of long neuronal extensions from the amygdala (green) contact neurons of the hippocampus (blue). This communication pathway helps to modulate anxiety. (Credit: Ada Felix-Ortiz/MIT)
Researchers at MIT’s Picower Institute for Learning and Memory  havediscovered a communication pathway between two brain structures — the amygdala and the ventral hippocampus — that appears to control anxiety levels.
By turning the volume of this communication up and down in mice, the researchers were able to boost and reduce anxiety levels. The research could help find better drugs to treat anxiety.
Measuring anxiety
Both the hippocampus, which is necessary for memory formation, and the amygdala, which is involved in memory and emotion processing, have previously been implicated in anxiety. However, it was unknown how the two interact.
To study those interactions, the researchers turned to optogenetics, which allows them to engineer neurons to turn their electrical activity on or off in response to light. For this study, the researchers modified a set of neurons in the basolateral amygdala (BLA); these neurons send long projections to cells of the ventral hippocampus.
The researchers tested the mice anxiety levels by measuring how much time they were willing to spend in a situation that normally makes them anxious. Mice are naturally anxious in open spaces where they are easy targets for predators, so when placed in such an area, they tend to stay near the edges.
When the researchers activated the connection between cells in the amygdala and the hippocampus, the mice spent more time at the edges of an enclosure, suggesting they felt anxious. When the researchers shut off this pathway, the mice became more adventurous and willing to explore open spaces. However, when these mice had this pathway turned back on, they scampered back to the security of the edges.
In future studies, the MIT team plans to investigate the effects of the amygdala on other targets in the hippocampus and the prefrontal cortex, which has also been implicated in anxiety.
“The practical use of this innovation is the identification of a novel target for potential anxiety treatment,” Kay Tye, an assistant professor of brain and cognitive sciences and member of MIT’s Picower Institute for Learning and Memory, explained to KurzweilAI. “While the time frame to translation to a treatment that could be used in humans is difficult to predict, we are taking the first step in developing more effective treatments for anxiety: identifying the critical neural substrates involved in controlling anxiety states.”
Anxiety disorders, which include post-traumatic stress disorder, social phobias and obsessive-compulsive disorder, affect 40 million American adults in a given year. Currently available treatments, such as antianxiety drugs, are not always effective and have unwanted side effects.
The research was funded by the JPB Foundation, the Picower Institute Innovation Fund, the Whitehall Foundation and the Klingenstein Foundation.
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Friday, 9 August 2013

stress


MONDAY, AUGUST 05, 2013

The bad kind of stress - perceived helplessness

Velasquez-Manoff does a nice discussion of a topic that has been recurrent in MindBlog, understanding the kind of stress that is really bad for us. Not the stress that goes with daily personal and professional aggravations, but the long term stress that derives from feeling helpless to control our lives. Numerous studies, the best known being a long term study of British civil servants, have shown that being higher in a social hierarchy correlates with having better health. The sense of control:
...tends to decline as one descends the socioeconomic ladder, with potentially grave consequences. Those on the bottom are more than three times as likely to die prematurely as those at the top. They’re also more likely to suffer from depression, heart disease and diabetes. Perhaps most devastating, the stress of poverty early in life can have consequences that last into adulthood.
The article quotes Robert Sapolsky at Stanford, whose classic book "Why Zebras Don't Get Ulcers" is still a must read, as saying:
Early-life stress and the scar tissue that it leaves, with every passing bit of aging, gets harder and harder to reverse...You’re never out of luck in terms of interventions, but the longer you wait, the more work you’ve got on your hands.
Bruce McEwen and others talk about
...the “biological embedding” of social status. Your parents’ social standing and your stress level during early life change how your brain and body work, affecting your vulnerability to degenerative disease decades later. They may even alter your vulnerability to infection. In one study, scientists at Carnegie Mellon exposed volunteers to a common cold virus. Those who’d grown up poorer (measured by parental homeownership) not only resisted the virus less effectively, but also suffered more severe cold symptoms.
Another clip:
Animal studies help dispel doubts that we’re really seeing sickly and anxiety-prone individuals filter to the bottom of the socioeconomic heap. In primate experiments females of low standing are more likely to develop heart disease compared with their counterparts of higher standing. When eating junk food, they more rapidly progress toward heart disease. The lower a macaque is in her troop, the higher her genes involved in inflammation are cranked. High-ranking males even heal faster than their lower-ranking counterparts. Behavioral tendencies change as well. Low-ranking males are more likely to choose cocaine over food than higher-ranking individuals.
Finally:
...while Americans generally gained longevity during the late 20th century, those gains have gone disproportionately to the better-off. Those without a high school education haven’t experienced much improvement in life span since the middle of the 20th century. Poorly educated whites have lost a few years of longevity in recent decades.
A National Research Council report, meanwhile, found that Americans were generally sicker and had shorter life spans than people in 16 other wealthy nations. We rank No. 1 for diabetes in adults over age 20, and No. 2 for deaths from coronary artery disease and lung disease. The Japanese smoke more than Americans, but outlive us — as do the French and Germans, who drink more. The dismal ranking is surprising given that America spends nearly twice as much per capita on health care as the next biggest spender.