Jayne Jubb

Halos, auras, flashes of light, pins and needles running down your arms, the sudden scent of sulphur—many symptoms of a migraine have vaguely mystical qualities, and experts remain puzzled by the debilitating headaches’ cause. Researchers at Harvard University, however, have come at least one step closer to figuring out why women are twice as likely to suffer from chronic migraines as men. The brain of a female migraineur looks so unlike the brain of a male migraineur, asserts Harvard scientist Nasim Maleki, that we should think of migraines in men and women as “different diseases altogether.”

Maleki is known for looking at pain and motor regions in the brain, which are known to be unusually excitable in migraine sufferers. In one notable study published in the journal Brain in 2012, she and her colleagues exposed male and female migraineurs to painful heat on the backs of their hands while imaging their brains with functional MRI. She found that the women had a greater response in areas of the brain associated with emotional processing, such as the amygdala, than did the men. Furthermore, she found that in these women, the posterior insula and the precuneus—areas of the brain responsible for motor processing, pain perception and visuospatial imagery—were significantly thicker and more connected to each other than in male migraineurs or in those without migraines.

In Maleki’s most recent work, presented in June at the International Headache Congress, her team imaged the brains of migraineurs and healthy people between the ages of 20 and 65, and it made a discovery that she characterises as “very, very weird.” In women with chronic migraines, the posterior insula does not seem to thin with age, as it does for everyone else, including male migraineurs and people who do not have migraines. The region starts thick and stays thick.

It is not yet known whether the thickening of the insula is something the brain is doing to protect itself or something that worsens women’s migraines. Yet the evidence is mounting that when it comes to migraines, men’s and women’s brains are structurally and functionally different. For treatment, that knowledge could make a huge impact: not only should researchers be better about testing potential migraine drugs on men and women separately, Maleki says, but they may be able to design new treatments based on these brain differences—giving both sexes a better chance at relief.

Migraines can be debilitating, and most people know somebody who regularily suffers from them. Here are the top (scientifically proven) triggers:

■ Overuse of painkillers

■ Foods:

• • Processed, fermented, pickled or marinated foods
  • Chocolate, nuts, peanut butter and dairy products
  • Foods containing tyramine: red wine, aged cheese, smoked fish, chicken livers
  • Fruits and vegetables: avocadoes, bananas, citrus fruits, onions
  • Meats containing nitrates: bacon, hot dogs, salami, cured meats

■ Changes in hormones, such as menstruation

■ Sex

■ Atypical sleep patterns

Deciphering Cluster Headaches

Migraines are not the only culprits when it comes to extraordinary head pain. Cluster headaches have long puzzled researchers, too, although studies are slowly revealing the parts of the brain involved when those punctuated bursts of pain occur.

The excruciating headaches tend to turn up in bouts lasting six to eight weeks. During these cycles, afflicted individuals—more often men—experience intense daily headaches on one side of the head, each lasting an hour or two.

In the late 1990s Goadsby and his colleagues linked cluster headaches to heightened synaptic activity falling in or near the hypothalamus, a brain region that mediates hunger, thirst, sleep, sex drive and more. Yet researchers are still trying to understand how activity in this hypothalamus-adjacent area could conjure the condition—and to determine what other glitches in brain structure, metabolism or interactions contribute to sufferers’ throbbing heads.

At least one study suggests that in cluster headache sufferers this hypothalamus-adjoining region may differ not only in its electrical activity but also in its interactions with other parts of the brain. In February 2013, a Beijing-based team imaged the brains of a dozen men in the midst of cluster headache bouts. The researchers traced blood flow—and, with it, functional connections—between the hypothalamus and other parts of the brain. Compared with unaffected men, the cluster headache sufferers did have unusual hypothalamic connections. When headaches hit, these altered interactions often involved parts of the brain associated with pain processing. But hypothalamic connections were off-kilter between headaches, too, pointing to more persistent brain differences in those prone to cluster headaches.

People often think of love and lust as polar opposites—love as the binder of two souls, lust the transient devil on our shoulders, disturbing and disruptive. Now neuroscientists are discovering that lust and love work together more closely than we think. Indeed, the strongest relationships have elements of both.

The divided treatment of love and lust dates to antiquity. The study of love as an academic subject is nearly a century old, with the sentiment covered in introductory text­books of social psychology. Psychologists, primatologists, neuroanatomists and neurophysiologists came to see love— defined as an intense and complex feeling of deep affection— as responsible for long­term coupling and close relationships. The first psychological tools for measuring love appeared in the 1940s. In a review of the literature published in 2011, psychologist Elaine Hatfield identified 33 scales for measuring love’s gradations.

In contrast, researchers have traditionally regarded lust as little more than uncontrolled sexual urges. The scientific study of lust remained verboten or limited to clinicians, psychiatrists and sex therapists dealing with social and behavioural problems. When the topic of lust did appear in the scientific literature, it was cast as an archaic emotion, a sinful feeling that needed to be suppressed or denied lest it challenge societal order, or an addiction that hijacked human thought, emotion and behavior in insidious ways.

Now, though, neuroimaging investigations are beginning to flesh (pardon the pun) out the relationship between lust and love. Some research does support the Jekyll and Hyde dichotomy. Studies have revealed that lust and love both have unique brain signatures, suggesting they are separable, with the brain able to generate lust in the absence of love and vice versa. In one study of 500 individuals conducted in the mid­1960s by psychologist Dorothy Tennov, 53 percent of the women and 79 percent of the men agreed with the statement, “I have been sexually attracted without feeling the slightest trace of love”; 61 percent of the women and 35 percent of the men agreed with the statement, “I have been in love without feeling any need for sex.” Neuroimaging studies have also shown considerable overlap between the network for lust and the network underlying addiction, suggesting that the craving associated with lust brings with it impulsivity, lack of self­control and risk taking.

Other studies reveal a more complex and synergistic connection between lust and love. Both feelings can activate regions in the brain related to emotions, including euphoria, reward, motivation, addiction and body image. What is more, lust and love activate different parts of the same brain structures, the insula and the striatum (in the pictures below love=red and lust=purple).

A recent meta­-analysis that was conducted of 20 studies with a total of 429 participants revealed that the posterior region of the insula activates more for lust than love and the anterior region of the insula activates more for love than lust. This back­to­front distinction is in line with a broader principle of brain organisation: posterior regions are involved in current, concrete sensations, feelings and responses, and anterior regions are involved in the integration of abstract concepts ranging from the distant past to alternative futures. In this model, lust would be grounded in particular sensory and motor experiences, with love as a more abstract, future­oriented gloss on those experiences with another person.

Studies show that as lust progresses to love, activity cascades from the back of the insula to the front, with the pleasing sensations of lust (sparked at the back) joined by the abstract feelings of affection (triggered at the front). A similar pattern for lust and love emerges in the striatum, this time travelling from bottom to top.

The research suggests that the strongest relationship – passionate love – involves activation of the home bases of both love and lust. Passionate love builds on the neural circuitry for lust, adding regions associated with reward expectancy, habit formation, and abstract representation and control to those associated with rewards for sensations and the satisfaction of cravings.

For any two individuals, the strongest relationship is not necessarily the best outcome: some couplings are just meant to be one­night stands. Love and lust can exist in any combination, with either, both or neither emotion present, and present to any degree. The combinations result in a variety of affiliations. When both people feel the same emotions, the relationship can range from passionate love (high love, high lust) to acquaintanceship (a little of each), with one­night stands (high lust, little love) and companionate love (as in a friendly marriage) in the middle. When the feelings of two people diverge, the results may be unwanted attention for one and unrequited love or lust for the other. The ideal state in any pairing is when the two people agree on their love­lust formula, creating a healthy balance between love and desire and the best chance for a stable, satisfying, monogamous relationship. But whatever the end point, getting there is half the fun!

References:

◆Love and Sex: Cross-Cultural Perspectives. Elaine Hatfield and Richard L. Rapson. Reprint edition. University Press of America, 2005.

◆The Common Neural Bases between Sexual Desire and Love: A Multilevel Kernel Density fMRI Analysis. Stephanie Cacioppo et al. in Journal of Sexual Medicine, Vol. 9, No. 4, pages 1048–1054; April 2012.

◆Lust for Life. Stephanie Cacioppo and John T. Cacioppo. Scientific American Mind, Vol. 24, No.5, pages 56-60; November/December 2013.

I have mentioned here before my love of writing and languages. In the last weeks, several articles have caught my attention around not only the healing power of writing but also how our choice of words & metaphors can influence ourselves and others. In the vein of wanting to wish you all manner of good things for 2014 I thought I could not do any better than to put words to the research….

Metaphors in Our Surroundings Can Trigger Thinking and Behaviour

During the last years I have taken myself out for a walk in the park daily if I can, but if not, then several times a week.

What started as a need to get me out from behind my computer and into the daylight for fresh air during an intense scientific research project, turned out to be one of the best daily habits I’ve ever made. It also transpired that I had a vitamin D deficiency, and so the daily boosts of sunlight were exactly what the doctor order, literally and metaphorically speaking.

As you look around you now, in this moment, what do you see? Do you see four walls or an expansive vista? The answer could influence your ability to think creatively. A growing body of research suggests that our sensory experiences can trigger metaphorical thinking, influencing our insights and behaviour without us even realising it. New research reveals ways we might be able to harness these subconscious forces.

Consider, for example, the metaphorical idea that the heart is warm and emotional and the head is cool and rational. In a study in August 2013 in the Journal of Personality and Social Psychology, researchers led their subjects to believe they were investigating how people answer questions when using their nondominant hand. To ensure they did not use their dominant hand, the participants were instructed to place their dominant index (pointer) finger either on their temple or on the left side of their chest. Participants who pointed at their head answered test questions more accurately, and those who pointed at their heart were more likely to let emotions sway their decisions in a moral dilemma. The finding adds to a rapidly growing list of metaphor effects: past studies have found that seeing forward motion can propel us to “move forward” in a metaphorical sense and that feeling smooth textures makes a difficult social interaction feel easier (or go more “smoothly”).

In all these studies, the influence of the embodied metaphors evaded conscious awareness—the study subjects did not notice the connection between their sensations and their subsequent decisions or feelings. Yet researchers think we might be able to use this effect by altering our surroundings and habits, such as choosing office art that evokes forward motion. If you are actively touching an object with the expectation that it will change your view of a situation, it might not work right away,” explains Joshua Ackerman, a psychologist at the Massachusetts Institute of Tech- nology and a co-author of the smoothness study. “But if you make such be- havior a habit, you will gradually stop thinking about the connection, and it will then have a stronger effect.”

In a similar vein, freeing yourself from perceived constraints may indeed facilitate “thinking outside the box.” In a series of experiments published in May 2012 in Psychological Science, scientists tested participants’ creative thinking while they literally sat inside or outside a cardboard box. Other participants either walked freely or along the path of a rectangle. Subjects who were outside the box in either sense scored higher on standard measures of creative thinking. You can imagine that this means you might be able to encourage your own creativity by eliminating constraints to movement, such as by strdiing around around a room or wandering through a park. The key is variety and spontaneity: if you want to be more creative, run freely outside and do it randomly for the day. Get away from your typical route, time of day, music or even your pace.

In any situation, consider your surroundings, sensory perceptions and actions—they might be influencing your thought process via the subtle metaphors embedded in daily life.

Figurative Speech Sways Decisions

When pondering a decision or trying to convince others, think carefully about your metaphors. The implicit information may subtly influence decision making.

A study published very recently examined how reading different metaphors—“crime is a virus” and “crime is a beast”—affected participants’ reasoning when choosing solutions to a city’s crime problem. Those who read the beast metaphor were more likely to opt for a direct approach emphasising enforcement, whereas the virus metaphor elicited a preference for a systemic, reform-focused solution. A follow-up survey indicated that many participants did not remember the metaphor they read, and none thought a metaphor could have influenced their reasoning.

People don’t seem to consciously ponder the ways in which crime is like a virus or beast. Instead metaphors subtly structure the way the person understands the issue being described.

Previous brain-imaging research has shown that interpreting metaphors requires a variety of areas on both sides of the brain, compared with literal language, which is processed in known language areas in the left hemisphere.

Scientists do not yet know how exactly this pattern affects reasoning, but they suspect that the brain triggers related concepts when processing a metaphor’s meaning. So it is perhaps worth giving more thought to the metaphors you use and hear, especially when the stakes are high. Ask in what ways does this metaphor seem appropriate and in what ways does this metaphor mislead. Our decisions may become sounder as a result!

Expressive Writing May Lead to Faster Recovery From Injury

Expressive writing is known to help ease psychological trauma and improve mood. Now studies suggest that such writing, characterised by descriptions of one’s deepest thoughts and feelings, also benefits physical health.

In a study published in July last year in Psychosomatic Medicine researchers in New Zealand investigated whether expressive writing could help older adults heal faster after a medically necessary biopsy. In the study, 49 healthy adults aged 64 to 97 years wrote about either upsetting events or daily activities for 20 minutes, three days in a row. After a time lag of two weeks, to make sure any initial negative feelings stirred up by recalling upsetting events had passed, all the subjects had a biopsy on the arm, and photographs over the next 21 days tracked its healing. On the 11th day, 76 percent of the group that did expressive writing had fully healed as compared with 42 percent of the control group.

The researchers concluded that writing about distressing events helped participants make sense of the events and reduce distress. Long-term emotional upset can increase the body’s levels of stress hormones such as cortisol, which impedes the immune system. A paper in September 2013 in the British Journal of Health Psychology indeed found that writing about an emotional topic lowered participants’ cortisol levels.

The writing in the New Zealand study may have also sped recovery by improving sleep. Participants who slept more in the week before the biopsy healed faster, perhaps because sleep increaes many bodily processes involved in healing.

A Change of Perspective Can Offer Solace

If a past ordeal continues to trouble you, try writing about it as if it happened to somebody else: “She crashed the car,” rather than “I crashed the car.” In a study that appeared in February 2013 in Stress and Health, doing so led to greater health gains for participants who struggled with trauma-related intrusive thinking, as measured by the number of days their normal activities were restricted by any kind of illness. It would seem that third-person expressive writing might provide a constructive opportunity to make sense of what happened but from a safe distance that feels less immediate and threatening.

This is interesting in that there are several healing modalities that use techniques in which, for example, you re-envisage the trauma as though it were happening on a television screen, thus creating distance.

I love it when science catches up with the alternative & natural medicine world!!

With Christmas and the ‘Festive Season’ rapidly approaching, it seems that every year there is increasingly more focus on the amounts of food we buy, make and consume. In the days leading up to Christmas our local Amsterdam supermarket looks as though there is going to be a famine because people are pilling up their trolleys as if there will not be a tomorrow.

When did it all get so crazy? How did it all get so crazy?

I decided to delve into the research around getting addicted to food….

In the United States more than two thirds of the population is overweight or obese, and that proportion continues to rise, even as public awareness of the importance of healthy eating is at an all-time high. Before we Europeans start to get too comfortable on our increasing posteriors, know that the same problem is occurring here too. Most people have a good idea of what a healthy diet looks like, so why is eating (less) such a difficult process? It turns out that every decision we make about eating is influenced by mental and physiological forces that are often outside of our awareness and control.

The path to gluttony looks something like the following. We start with the occasional experience of eating too much— say five handfuls of salted nuts instead of two, or a larger-than-normal portion of dessert, before realising we are uncomfortably full. The way a particular food looks, tastes and feels in our mouth can trick our brain into eating well past necessity from an energy standpoint, and modern foods (think: processed, packaged goods) are especially effective at this deception. The brain response to high-sugar, high-fat foods is much stronger than to foods found in nature. The food industry amps up those responses to a point where our brain is really going to react.

New research is revealing that those occasional bouts of overeating and eating for pleasure, rather than out of hunger, can push us further down the path to gluttony, priming our brain to want that hedonistic experience more and more. Humans who overeat may develop the same patterns of neural activity in areas of the brain associated with rewarding experiences as drug addicts do, and many rodent studies have found that eating high-sugar or high-fat diets prompt cycles of craving and withdrawal along with brain changes similar to those that accompany drug addiction. For many people, these brain changes lead to addiction-like behaviours with certain foods — for instance, consistently consuming more than they intended to or feeling regret and shame after many meals.

Although the concept of food addiction is still controversial, many scientists now believe that considerably more than half the population struggles with its symptoms, in large part because of the widely-available high-sugar, high-fat foods. We may not all be equally at risk or equally vulnerable, but the fact that we’re all in this environment makes us all vulnerable to some degree.

The good news is that knowing how our surroundings push us toward gluttony, we can push back, psyching ourselves into eating less and feeling better. We’re battling an environment that is completely cueing us to eat all the time. The goal is to eat more foods that are minimally processed. Keep that bowl of fruits and vegetables on the counter, the pack of almonds in your purse. In other words, be a glutton for nourishment instead of punishment.

Oops, I Ate the Whole Bag

Eating is at once a great pleasure and a dire necessity. Early studies in the mid-20th century largely focused on the necessity component: scientists successfully teased out how our body regulates our appetite in response to changing energy demands. For instance, when a casual runner starts training for a marathon, s/he needs to consume more calories daily to power her muscles over those longer distances, so his/her appetite increases. This internal regulation is the product of a complex system of hormones and neurotransmitters that make us feel hungry when we need more energy and sated when we have enough in the tank. Past attempts to develop drugs for weight control focused on these appetite mechanisms, but many researchers now feel that was a mistake.

Pioneering neuroscientist food addiction researchers say that they “don’t want people to not eat; we want them to not eat only for pleasure”. By shifting the focus to the hedonistic aspect of eating, scientists in the past two decades have uncovered many additional psychological and neural mechanisms that contribute to overeating—not only in one sitting, when a food’s taste and texture influence our desire to keep eating, but also in the long term, when addiction-like behaviors can set in.

When we bite into, for example, a crisp (chips in Dutch, potato chip in American), the sensory experience is immediate and intense: crunchy, salty, rich. The desire for those crisps depends more on these sensory qualities than the need for sustenance; you will stop eating them when you are tired of putting crunchy, salty things in your mouth. Scientists call that halting point “sensory-specific satiety,” and research has shown that it has nothing to do with metabolic satiety, which is the feeling of “fullness” that signals the body has consumed enough energy. We have all heard the advice to eat slowly, so your body has a chance to sense when it is full—but that takes at least 20 minutes, which is far longer than we typically spend on a snack or a light meal. Sensory-specific satiety theoretically happens a lot sooner, in minutes or even a few bites, explains nutritional scientists.

According to research in the 1990s, sensory-specific satiety is processed in the orbitofrontal cortex, a region of the brain just behind the brow involved in sensory integration, reward processing and decision making. Neurons in that region respond strongly when we first taste a food, and the response gets weaker with each subsequent bite. When a different food is introduced, neuron activity jumps back to the high initial levels, instigating a response that can spur us to eat more even if we are full, as long as the next bite has a radically different sensory profile than what we had previously eaten. In other words, there is always room for dessert. This work suggests that you can reduce your intake by limiting your choices. Try to avoid having a variety of foods in one meal; avoid the ‘smorgasbord’ type buffet.

Over time, on the other hand, you may need some variety to get around another fattening phenomenon. In the first long-term study of sensory-specific satiety published in 2012, nutritional scientists asked 118 study participants to eat either chocolate, hazelnuts or crisps (potato chips) every day for 12 weeks. Afterwards the participants were slower to reach sensory-specific satiety when eating their assigned snack food. The familiar banality of the food, the authors speculate, seems to prevent it from becoming unpalatable. As a result, people robotically consume it. So although it may be wise to stick to one or two foods at every meal, do not eat the same foods day in and day out, or you may gradually eat more, perhaps without knowing it.

Studies on sensory-specific satiety also reveal that the flavour profile of the food you eat makes a dramatic difference in how much of it you want in one sitting. People reach this type of satiety much more quickly when they eat foods that have complex, intense or unfamiliar flavours, as opposed to mild or one-note taste profiles. So if your goal is to eat less without really thinking about it, choose spicy and rich over bland and light: a fiery curry instead of your go-to chicken soup, extra-dark rather than milk chocolate, Granny Smith apples—or better yet, a fruit you have not tried before—over Golden Delicious. The more exciting the flavour, the quicker you will feel satisfied.

When Indulgence Triggers Compulsion

The occasional episode of overeating, in theory, should not be problematic for our body to handle. We should simply feel full longer, as our body waits for the energy it just consumed to get used up before prompting us to eat again. Unfortunately, our survival-focused brain has other ideas. Bingeing was probably useful in our evolutionary past, when food was scarce and our ancestors needed to eat as much as possible after they came across a berry patch or brought down a fresh kill on the hunt. Yet our food environment is quite different today. Now that you can open the refrigerator or go to a supermarket, this response is absolutely unnecessary. But your brain is still operating in a way that is producing a rewarding response. The obese rats had fewer receptors for the neurotransmitter dopamine, which signals pleasure, in the striatum, a brain area activated by rewarding stimuli. Fewer receptors suggest a lowered sensitivity to a substance such as food, an effect that may motivate an animal to consume more to get the same “high.” Similar decreases in dopamine receptors are seen in overweight people, as well as rodents and humans addicted to cocaine and heroin.

Being surrounded by a large variety of extremely delicious food plays a key role in triggering this rewarding brain response in some people. Studies on the rodent equivalent of a nearby open-all-hours supermarket—unlimited access to a variety of high-sugar, high-fat foods—find that this food environment makes rats start eating compulsively. For example, in 2010 neuroscientists reported that rats that could eat whenever they wanted from a buffet of highly palatable foods ate more and more over time, became obese, and showed a disruption of the reward function in their brain compared with control rats fed normal amounts.

Another risk factor for overindulging is, well, having over-indulged. That is, once a person has binged, the behaviour can trigger more of the same. In a study published in 2011 rats bred to be prone to binge eating were compared with those bred to be resistant. As expected, the binge eaters ate uncontrollably when given access to unlimited food, even crossing a metal plate that gave them a foot shock to get to that food. The binge-resistant rats refused to cross the plate—until the researchers began feeding them a cyclic diet of massive amounts of food followed by very little food. These rats then began overeating when given the chance and even endured the shock to get to the food. Being willing to endure pain to get to a desired substance is a hallmark of addiction.

If humans are like rats, then dieters who break a strict diet with a binge may be putting themselves at risk for addiction. The cycle of caloric restraint followed by overindulgence could make the brain even more sensitive to food cues. The psychology of this binge-restrict pattern might rset people up to have an addictive response. Other work suggests that frequently eating extremely palatable food high in sugar and fat may trip a kind of trigger for overeating in the nucleus accumbens, a brain site that evolved to direct us toward things that were evolutionarily advantageous. In previous work, scientists had seen that rats would frantically binge after injections into their nucleus accumbens of a drug that mimicked the neurotransmitter gamma-amino-butyric acid (GABA). Researchers became curious about whether this phenomenon was relevant to ordinary eating behaviour. In a study published very recently it was shown that a high-sugar, high-fat diet prompts the nucleus accumbens of rats to be hypersensitive to GABA. In addition, it was found that injecting endogenous opioid peptides, known pleasure molecules, into the nucleus accumbens induced the same hypersensitivity as the palatable diet. The findings explain how a diet consistently high in sugar and fat can prompt overeating: the repeated rushes of opioid peptides that accompany habitual consumption of pleasurable food sensitise the nucleus accumbens so that a small surge of the omnipresent GABA could bring on a binge. If you eat a little bit and the on switch is sensitised, you might lose con- trol and not be able to stop…..

Sugar Withdrawal?

In 2006 at Brighton Hospital, a substance abuse treatment center in Michigan, then training director John Hopper was noticing something strange about his patients. Many of them had recently had bariatric surgery, such as a gastric by-pass, to lose weight. They had shed kilos—but became saddled with another heavy weight: a drug or alcohol addiction, many for the first time in their lives. Hopper decided to investigate further investigate. In 2010 it was reported that 2 to 6 percent of the hospital’s clients had had bariatric surgery—a rate at least 100 times higher than in the general population, suggesting that something about bariatric surgery puts people at risk for addiction. It is now believed that bariatric surgery removed these patients’ ability to feed their addiction to food— and so they replaced food with a different “drug.” These are middle-aged men and women, of modest or good socioeconomic status, suddenly eating pills or drinking boxes of wine, totally out of control….

In the reverse phenomenon, recovering drug and alcohol addicts tend to gain a lot of weight— as if replacing their drug with food. And it has long been known that food and drugs compete for the same reward systems in the brain, bolstering the argument that food has addictive qualities similar to those of drugs. Some data also suggest that sugars and fats can induce withdrawal: the distress, cravings and pain that can occur when an individual suddenly stops habitually consuming drugs or alcohol. For example, in a study published in 2012 fed rats a high-fat, sugary diet for six weeks. When they abruptly returned the rats to their normal fare, the rodents became anxious, displaying fearful behaviour such as avoiding open areas. They also showed increased motivation to get to either high-fat or high-sugar food: they were willing to press a lever more times to obtain a sugar or fat pellet. In the rats’ brain, the scientists also found elevated levels of certain chemicals characteristic of drug withdrawal. In other experiments, the researchers showed that not all fats lead to these withdrawal signs in rats. The monounsaturated fats present in olive oil and avocados seem to be far less problematic than the saturated types prevalent in butter, red meat and many processed foods. Food addiction is apparently distinct from obesity.

Many food addicts have a normal weight, and the rats in the study displayed withdrawal symptoms without becoming obese. In addition, some obese people are not food addicts. To separate those who might be addicted from those who just tend to gain weight, a food addiction scale was created:

Though intriguing, the idea of food addiction remains unproved. Not all criteria for drug addiction apply when the putative addictive substance is food. We need food to survive in a way we do not need recreational drugs. For example, irritability, lethargy and a tendency to seek out the substance in its absence are not signs of pathology when it comes to food. We may, after all, just be hungry. As a result, experts need to agree on an adjusted definition of addiction in this case. And unlike drugs, food in general cannot be defined as an addictive substance; scientists still need to tease out which foods or ingredient combinations are the most likely to lead to addiction.

Nevertheless, experts agree that certain foods trigger what are clearly addiction-like behaviours in some people. And the food addiction concept is gaining momentum in the face of accumulating data supporting it and new thinking about obesity. In June the American Medical Association officially recognised obesity as a disease. Many experts think acceptance of food addiction cannot be far behind. Some say that if society were to embrace the idea that sugary, fatty foods are dangerous enough to be taxed, regulated and avoided the way cigarettes are today, we would have a better chance of reversing the obesity epidemic.

For now we can use the lessons from recent research to put ourselves on a fitter path. To enlist sensory-specific satiety as an aid, choose flavourful or unusual foods and carefully regulate the amount of food choice you give yourself at any given sitting—and over time. In addition, realise that just walking past a vending machine at work or sitting down in front of the television can trigger a craving. Make sure you are aware of and avoid situations where you are conditioned to eat. A lot of people eat when they are bored or stressed, so instead of turning to food at those times, train your brain to want a more beneficial reward, such as taking a walk. And when you do find yourself unable to resist the junk food— at a party for instance—go ahead and have some but keep your portions moderate. Your small indulgence may prevent a far bigger fall off the wagon.

References:

◆ Further Developments in the Neurobiology of Food and Addiction: Update on the State of the Science. Nicole M. Avena, Jessica A. Gold, Cindy Kroll and Mark S. Gold in Nutrition, Vol. 28, No. 4, pages 341–343; April 2012.

◆ Long-Term Consumption of High Energy-Dense Snack Foods on Sensory-Specific Satiety and Intake. Siew Ling Tey et al. in American Journal of Clinical Nutrition, Vol. 95, No. 5, pages 1038–47; May 2012.

◆ “I Didn’t See This Coming”: Why Are Postbariatric Patients in Substance Abuse Treatment? Patients’ Perceptions of Etiology and Future Recommendations. Valentina Ivezaj, Karen K. Saules and Ashley A. Wiedermann in Obesity Surgery, Vol. 22, No. 8, pages 1308– 1314; August 2012.

◆ Salt, Sugar, Fat: How the Food Giants Hooked Us. Michael Moss. Random House, 2013.

◆ Food Addiction? Special issue of Biological Psychiatry, Vol. 73, No. 9; May 1, 2013.

I love it when science catches up with what we ‘know’ from natural medicine. Recently several studies have caught my attention in which ‘treating the mind’ relieves physical symptoms.

Gastritis and Anxiety

People with gastritis—a blanket term for stomach and intestinal discomfort, including heartburn, nausea and abdominal pain— are nearly twice as likely as the general population to suffer from anxiety and mood disorders, according to a study published in the January Journal of Psychiatric Research. But even in patients with no known mental issues, psychotherapy improves gut health, as research published online in February in the Asian Journal of Psychiatry showed. Study participants with indigestion who received 16 weeks of a therapy aimed at helping them identify and correct dysfunctional interpersonal patterns, called core conflictual relationship theme (CCRT) psychotherapy, saw improvements in all their gastrointestinal symptoms—and their mental health—which lasted for at least a year.

Ulcers and Depression

Renee Goodwin, professor of psychology at Queens College and the City University of New York and co-author of the January gastritis study, and her colleagues are currently researching the relation between ulcers and depression and anxiety. Preliminary data, Goodwin says, suggest that patients treated for depression were much less likely to have an ulcer 10 years later, compared with those who were not treated.

Tinnitus and Stress

Tinnitus, or persistent ringing in the ears, affects 50 million Americans. A study published online in January in Quality of Life Research found that about half of tinnitus sufferers also have mental disorders, confirming the findings of previous research. A 2012 study found that emotional stress more strongly predicts tinnitus than other known risk factors, perhaps because the emotion-processing areas of the brain are closely connected to its auditory systems. A small study in the January Mindfulness found that reducing stress with mindful meditation alleviated tinnitus symptoms and lowered sufferers’ perceived handicap.

Asthma and Depression

Research has hinted at a relation between asthma and depression. In a study published online in Psychosomatic Medicine last year, scientists found that a third of asthma patients also suffer from depression and that those individuals were more likely to have an asthma-related visit to the accident & emergency department over the yearlong study period. The findings suggest that treating depression could make asthma attacks less severe for patients who have both conditions.

Migraine and Panic Disorder

A meta-analysis published in the January Headache: The Journal of Head and Face Pain determined that migraine sufferers are almost four times as likely as nonsufferers to have panic disorder, an anxiety condition characterized by disabling panic attacks. Patients who have both conditions experience more negative effects from migraine, including more frequent attacks and increased disability. Todd Smitherman, a psychologist at the University of Mississippi and co-author of the paper, says there is a “dire need” for studies investigating whether treating panic disorder can reduce the frequency or severity of migraines.

Self-esteem, or a person’s overall sense of self-worth, is generally considered to be critical to healthy functioning. Its darker side, however, has been largely overlooked. The quest for greater self-esteem can leave people feeling empty and dissatisfied. Recent research bolsters the case. Even when we achieve goals we anticipate will make us feel good about ourselves, high self-esteem may still elude us because self-esteem that is dependant on success is fragile.

It turns out that having self-esteem, as a fairly stable personality trait, does have a few modest benefits. High self-esteem also has drawbacks, however, and is mostly irrelevant for success. Further the pursuit of self-esteem is clearly detrimental to well-being. When people chase after a stronger sense of self-worth, it becomes their ultimate goal, leading them to sacrifice other aspirations, such as learning or doing what is good for others.

The hunt for self-esteem through a focus on achievement makes us emotionally vulnerable to life’s inevitable travails and disappointments. It also causes us to engage in behaviours that can actually harm our chances of success, our competence and our personal relationships. A far better way to bolster your sense of self-worth is, ironically, to think about yourself less. Compassion toward others and yourself, along with a less self-centered perspective on your situation, can motivate you to achieve your goals while helping you weather bad news, learn from your mistakes and fortify your friendships.

Rocky Road

Scientists define self-esteem as the amount of value people place on themselves—an inherently subjective assessment. Researchers typically measure this value using self-report scales, including statements such as “I take a positive attitude toward myself,” indicating a positive evaluation of oneself, or “All in all, I am inclined to feel that I am a failure,” denoting a more negative self-appraisal. Someone with a highly favourable overall self-evaluation has high self-esteem; a person who judges himself or herself unfavorably has low self-worth.

Back in the 1980s, many academic psychologists, policy makers and others became concerned about low self-esteem among the populace. They argued that solving this problem would create more productive citizens and lead to fewer social ills such as crime and school failure. The self-esteem movement began. Schools and other institutions poured resources into interventions designed to raise self-esteem, particularly in children. These programs typically centred on lots of positive feedback—irrespective of performance—and exercises in which individuals expounded on their positive qualities. In “I Love Me” lessons, for example, students were encouraged to complete the phrase “I am …” with positive words such as “beautiful” or “gifted.” Those performing below grade level were taught to focus on their potential rather than their shortcomings. In 1986, for example, California allocated $245,000 a year to its Task Force to Promote Self-Esteem and Personal and Social Responsibility, under the assumption that the money would be repaid through lower rates of crime, welfare dependency, unwanted pregnancy, drug addiction and school failure.

Yet even as the self-esteem movement gained momentum, scientific research began to undermine some of its major assumptions. For one, the data did not show that many of us suffer from low self-esteem. On the contrary, most of us already feel pretty good about ourselves. In a study published in 1989 psychologist Roy Baumeister found that the average American’s self-esteem score is well above the conceptual midpoint of self-esteem scales—the point that denotes a moderate or decent view of the self. It would seem that most Americans have decided that they are above average.

What is more, our egos seem to be expanding, not contracting. In a study published in 2008 psychologists concluded that high school students like themselves more now than they did in the 1970s, even though they do not see themselves as more competent than previous generations did. That is, the students do not consider themselves better at math, music, sports or other activities than adolescents did in the past, but they think more highly of themselves anyway.

While documenting a plethora of self-esteem, researchers began to discount its importance. In a comprehensive review of the literature published in 2003 Baumeister stated that people with high self-esteem perform only slightly better academically and at work than do those with low self-esteem. Likewise, self-esteem is only weakly related to children’s popularity in school and tenuously tied to the quality of a person’s relationships in general. It also has little effect on how likely someone is to be violent or engage in risky behaviours such as smoking and drug use.

High self-esteem does have some benefits. It seems to make people more persistent. Those with high self-esteem also reported feeling happier and less depressed. Yet whether high self-esteem causes pleasant feelings, or vice versa, remains unclear.

High self-esteem seems to have at least one serious drawback: difficulty in seeing your own short-comings. A great deal of research conducted for several decades shows that people with high self-esteem tend to have unrealistically positive views of themselves. They think they are more attractive, successful, likable, smart and moral than others do—and are unaware of their deficits or incompetence. When they get negative feedback, they tend to be defensive, blaming the test or the messenger, rather than owning up to a mistake or deficiency. In this way, high self-esteem can impede learning and growth and impair personal relationships. When it comes to your brain surgeon (or spouse, for that matter), most of us would most likely prefer that person to have a realistic view of his or her abilities and a willingness to learn from mistakes—rather than high self-esteem.

“I Didn’t Try Hard”

The studies Baumeister analysed measured the trait of self-esteem with questions that get people to reflect about themselves in general, over time. When people are asked to indicate how they feel “right now” or “today,” self-esteem scores can fluctuate dramatically in response to events. These ups and downs affect motivation, because boosts to self-esteem feel good and drops feel lousy. Like mice looking for crumbs of cheese while steering clear of the mousetrap, people look for opportunities to inflate their self-esteem and avoid situations that could lower it.

One way to get those increases is to succeed or excel; likewise, we can try to avoid the drops by circumventing failure. Because we cannot succeed at everything, people tend to invest their self-esteem in one or a few traits or endeavours, say, academics, sports or beauty. These contingencies of self-esteem represent the areas in which people’s self-worth is on the line; they are worthy if they succeed and worthless if they fail. In 2003 a questionnaire was developed assessing such contingencies as academic success, appearance, others’ approval and moral virtue. People who base their self-esteem on academics, for example, say that their self-esteem goes up when they get good grades but that they feel worthless, anxious and ashamed when their grades are poor.

People who become so personally invested in certain domains are highly motivated to succeed in those realms, which often leads them to work hard. For example, Crocker and Luhtanen found that students whose self-esteem is contingent on academics report studying more than do students who depend less on such reports. On the other hand, putting your self-worth at the mercy of achievement in this way creates emotional vulnerability to setbacks. Even the most successful people sometimes fail or fall short, even at what they do best. Trading off occasional feelings of worthlessness for motivation and the highs of achievement might seem reasonable. Yet the exchange is not even: dips in self-esteem following setbacks appear to be much larger than the increases stemming from success.

In a study published in 2002 Crocker asked 37 university students applying for post-graduate education to fill out a questionnaire to assess how much they based their self-worth on their academic track record, personal appearance, and love of family and friends, among other areas. These students then completed measures of their self-esteem twice a week during the two-month season of post-graduate course admissions. It was found that students whose self-esteem was tightly bound to their academic success experienced small boosts on days when they received an acceptance notice but large drops on days they were rejected. For them, the pain of failure far outweighed the joy of success. The students whose self-esteem did not depend on academic performance experienced markedly less extreme fluctuations in their self-worth; they were better able to weather the storm of positive and negative feedback. Studies show that a similar vulnerability afflicts those whose self-esteem is contingent on appearance or career achievement.

In addition, an uptick in self-esteem is short-lived. Research shows that changes in self-esteem typically do not last more than a few days. Even after major accomplishments, self-esteem quickly returns to its average level. As a result, they are a relatively transient source of happiness. The instability that results from ups and downs of self-esteem, on the other hand, has significant costs to our mental health. In particular, it can lead to symptoms of depression. For example, the fluctuations in self-worth experienced by the post-graduate course applicants were associated with increases in depressed mood, feelings of hopelessness and helplessness, disruptions in appetite and sleep, and loss of motivation.

Perhaps the most pernicious cost of basing self-esteem on achievement is that it can sometimes lead people to focus on avoiding failure rather than reaching for success—a mind-set that can increase the chances of falling short. For example, to protect their self-esteem, people may create excuses for poor performance such as “I didn’t try hard” or “I was tired, sick or upset,” believing that such explanations suggest they could have done well under other circumstances. Yet to work, the excuse must be believable, so a person may stay up late before a test so that the “tired” excuse will be valid in the event they do badly or put off studying until the last moment so they can claim they were underprepared. Social psychologists have coined the phrase “self-handicapping” to describe such behaviour.

Pursuing self-esteem also undermines intrinsic motivation, the type driven by interest in the task itself. Psychologists Edward Deci and Richard Ryan have argued that contingent self-esteem is a form of ego involvement, in which people focus on how successes and failures reflect on the self. Their research, conducted over several decades, shows that individuals who are ego-involved do things such as studying and exercising because they feel that they have to, rather than because they want to. This sense of obligation and pressure takes away the satisfaction that can come from working hard at something difficult.

Personal relationships also suffer from the quest for self-esteem. People focused on boosting their own self-esteem tend to put their own needs before those of others. Because they are preoccupied with questions about their own value, their friends, family and acquaintances serve mainly as potential sources of validation or invalidation, making their interactions with others ultimately all about themselves.

Not all contingencies of self-esteem are equally damaging. Staking self-esteem on personal values such as religious faith or virtue seems to have fewer negative consequences than letting it ride on traits or skills such as appearance or prowess at math that others can measure or judge. The reasons for this discrepancy are not fully understood, but it may result from the fact that those who are driven to prove that they are virtuous or faithful to a religion may be more likely to engage in helpful, collaborative or philanthropic activities that others appreciate. Nevertheless, all such contingencies leave us somewhat vulnerable to the consequences of letting our self-esteem depend so heavily on the particulars that define us.

The Greater Good

Although the pursuit of self-esteem has many negative consequences, it also serves an important purpose: motivating us to action. Without the urge to prove our worth, might we turn into slackers? Fortunately, we can adopt another approach. Instead of focusing on our own status, we can focus on others or the collective good. For example, an individual might work just as hard at the office, but with the primary goal of contributing to the team’s mission or supporting his or her family rather than earning individual recognition. Goals directed at being constructive, supportive and responsive to others lead to feelings of connectedness, closeness to others, social support and trust, as well as reduced feelings of conflict, loneliness, fear and confusion.

Compassionate goals appear to engender a sense of worth and connectedness without the devastating drops that come after feedback suggestive of failure. In a study published in 2011 Crocker examined the consequences of compassionate goals in first year university students and their same-sex roommates. Every roommate rated the extent to which they had compassionate goals such as “be supportive of my roommate” and “be aware of the impact my behaviour might have on my roommate’s feelings”; they also answered a self-esteem questionnaire at the beginning and end of the semester and each week in between. In addition, participants rated their regard for their roommate, how responsive they viewed themselves as being to their roommate’s needs and how responsive they perceived their roommate to be to their own needs.

Students with compassionate goals were more receptive to their roommates’ needs, according to both the student and the roommate. Their roommates noticed and responded in kind, creating a virtuous cycle that solidified the relationship. Furthermore, the more responsive students were, the more their self-esteem increased during the three-month semester. Their roommates’ self-esteem also rose, suggesting that having compassion for others may be an effective strategy for boosting self-esteem over the long run. In contrast, the roommates who were primarily concerned with what their roommates thought about them were less responsive to their roommates, a pattern of behaviour that undermined their self-esteem and that of their roommate.

You can be compassionate toward yourself and others. If you find yourself upset by a mistake or downfall, self-compassion can make for a softer landing for your fall. People with self-compassion treat themselves kindly, as they would a close friend. They are patient with themselves, nonjudgmental and understanding of their own imperfections, according to work by psychologist Kristin. They also avoid harsh self-critiques or negative generalisations about self-worth following one negative experience. Self-compassion helps you accept life’s inevitable setbacks as simply part of what it means to be human. It allows you to see failure as a learning opportunity rather than a threat, something that can motivate you to work toward your goals.

Compassion for the self seems to be linked to compassion for others. In an experiment, research participants were asked to write a note designed to make a friend feel better after causing a minor car accident. Those participants then rated themselves as higher in self-compassion than participants who recalled a fun time or read about others’ suffering.

A further way to reduce an obsession with the self, and the problems that fixation generates, is to use a technique called self-distancing. Using this strategy, you see yourself from the perspective of a third-party observer, the proverbial “fly on the wall,” rather than from inside your own head. In a 2012 study psychologist Ethan Kross asked participants, on each of seven nights, to consider and answer questions about emotional events that had occurred during the previous day. In addition to noting the frequency, intensity and duration of the episodes, the subjects rated to what extent they had adopted a self-immersed versus distanced perspective when reflecting on each one. Those who adopted the distanced viewpoint recovered more rapidly from their negative feelings but also experienced briefer positive emotions than those who adopted the more self-centred outlook. The results suggest that creating mental distance from an emotional situation buffers us from the slings and arrows of fortune.

Another means of alleviating the sting of self- evaluation is self-affirmation, in which people restore their feelings of worth following negative feedback by reflecting on a value in a different realm that is important to them. For example, if someone gets drooped from a sport’s team, she might protect her self-esteem by, say, writing a paragraph about why science is personally meaningful to her or by simply donning a white lab coat. Such behaviours can temper the unpleasant emotions that accompany a critical evaluation. And recent work suggests that this kind of affirmation works best if the value transcends you. For example, thinking about how science can create a better world for all of us has a larger payoff than focusing on how science can win you wealth or status.

All these alternatives to pursuing self-esteem reduce the tendency to judge the self. By focusing on others, having self-compassion or adopting a distanced view of yourself, you can work toward your goals without constant self-evaluation and self-criticism. If we were to design a new self-esteem movement, it would teach people to reduce focus on the worth of the self altogether because any action designed to enhance self-esteem is destined to have, at best, temporary benefits and most likely will fail because such actions are motivated by a toxic preoccupation with self-judgment.

Helping others may make you feel good about yourself but only if you let go of what this means about you. If you are wondering, “Do I have worth?” “Do I have value?” the answer is not yes, no or maybe. The answer is simpler: change the subject ;=)

References:

◆Does High Self-Esteem Cause Better Performance, Interpersonal Success, Happiness, or Healthier Lifestyles? R. F. Baumeister, J. D. Campbell, J. I. Krueger and K. D. Vohs in Psychological Science in the Public Interest, Vol. 4, No. 1, pages 1–44; 2003.

◆The Curse of the Self: Self-Awareness, Egotism, and the Quality of Human Life. Mark R. Leary. Oxford University Press, 2007.

◆Transcending Self-Interest: Psychological Explorations of the Quiet Ego. Edited by Heidi A. Wayment and Jack J. Bauer. American Psychological Association, 2008.

◆Crocker Laboratory: http://faculty.psy.ohio-state.edu/crocker/lab/ index.php

◆Learning as Leadership: http://learnaslead.com

◆Letting Go of Self-Esteem. J. Crocker and J. J. Carnevale.Scientific American Mind, vol. 24, nr. 4, Sept/Oct 2013 pages 26-33.

September brings with it another acamdemic year – a time when the children go back at school, universities start up again, and people go back to work after the summer break. Each year at this time I notice the whiff off ‘wanting to learn’ wafting around in my surroundings. Not just my own curiosity but those of other people around me. It seems that the end of summer and the start of Autumn heralds cooler indoor days and time to embark on something new.

In spite of all the learning done in educational institutions, one thing we typically never study is the art of studying itself. In this month’s On the Border, I have combed through some of the scientific literature on learning techniques to identify the two methods that work best.

Education generally focuses on what you study, such as maths, the elements of the periodic table or how to conjugate verbs. But learning how to study can be just as important – and with lifelong benefits. It can teach you to pick up knowledge faster and more efficiently and allow you to retain information for years rather than days.

Cognitive and educational psychologists have developed and evaluated numerous techniques, ranging from re-reading to summarising to self-testing, for more than 100 years. Some common strategies markedly improve student achievement, whereas others are time-consuming and ineffective. Yet this information does not seem to be making its way into the classrooms and lecture theatres. Teachers today (even neuroscience and psychology professors!) are not being told which learning techniques are supported by experimental evidence, and students are not being taught how to use the ones that work well.

Both methods help learners of various ages, abilities and levels of prior knowledge—and they have been tested in a classroom or other real-world situation. Learners can use the methods to master a variety of subjects, and they also result in long-lasting improvements in knowledge and comprehension. Perfect!

1.SELF-TESTING: Quizzing Yourself Gets High Marks

HOW IT WORKS:

Unlike a test that evaluates knowledge, practice tests are done by students on their own, outside of class. Methods might include using flash cards (physical or digital) to test recall or answering the sample questions at the end of a textbook chapter. Although most students prefer to take as few tests as possible, hundreds of experiments show that self-testing improves learning and retention.

In one study, undergraduates were asked to memorise word pairs, half of which were then included on a recall test. One week later the students remembered 35 percent of the word pairs they had been tested on, compared with only 4 percent of those they had not. In another demonstration, undergraduates were presented with Swahili-English word pairs, followed by either practice testing or review. Recall for items they had been repeatedly tested on was 80 percent, compared with only 36 percent for items they had restudied. One theory is that practice testing triggers a mental search of long-term memory that activates related information, forming multiple memory pathways that make the information easier to access.

WHEN DOES IT WORK?

Anyone from pre-schoolers to fourth-year medical students to middle-age adults can benefit from practice testing. It can be used for all kinds of factual information, including learning words in foreign languages, making spelling lists and memorising the parts of flowers. It even improves retention for people with Alzheimer’s disease. Short, frequent exams are most effective, especially when test takers receive feedback on the correct answers.

Practice testing works even when its format is different from that of the real test. The beneficial effects may last for months to years— great news, given that durable learning is so important.

IS IT PRACTICAL?

Yes. It requires modest amounts of time and little to no training.

HOW CAN I DO IT?

Students can self-test with flash cards or by using the Cornell system: during in-class note taking, make a column on one edge of the page where you enter key terms or questions. You can test yourself later by covering the notes and answering the questions (or explaining the keywords) on the other side.

RATING:

High utility. Practice testing works across an impressive range of for- mats, content, learner ages and retention intervals.

2. DISTRIBUTED PRACTICE: For Best Results, Spread Your Study over Time

HOW IT WORKS:

Students often “mass” their study—in other words, they cram. But distributing learning over time is much more effective. In one classic experiment, students learned the English equivalents of Spanish words, then reviewed the material in six sessions. One group did the review sessions back to back, another had them one day apart and a third did the reviews 30 days apart. The students in the 30-day group remembered the translations the best. In an analysis of 254 studies involving more than 14,000 participants, students recalled more after spaced study (scoring 47 percent overall) than after massed study (37 percent).

WHEN DOES IT WORK?

Children as young as age three benefit, as do undergraduates and older adults. Distributed practice is effective for learning foreign vocabulary, word definitions, and even skills such as mathematics, music and surgery.

IS IT PRACTICAL?

Yes. Although text-books usually group problems together by topic, you can intersperse them on your own. You will have to plan ahead and overcome the common student tendency to procrastinate……

HOW CAN I DO IT?

Longer intervals are generally more effective. In one study, 30-day delays improved performance more than lags of just one day. In an Internet-based study of trivia learning, peak performance came when sessions were spaced at about 10 to 20 percent of the retention interval. To remember something for one week, learning episodes should be 12 to 24 hours apart; to remember something for five years, they should be spaced six to 12 months apart. Although it may not seem like it, you actually do retain information even during these long intervals, and you quickly re-learn what you have forgotten. Long delays between study periods are ideal to retain fundamental concepts that form the basis for advanced knowledge.

RATING:

High utility. Distributed practice is effective for learners of different ages studying a wide variety of materials and over long delays. It is easy to do and has been used successfully in a number of real-world classroom studies.

References:

◆ Ten Benefits of Testing and Their Applications to Educational Practice. H. L. Roediger III, A. L. Putnam and M. A. Smith in Psychol- ogy of Learning and Motivation, Vol. 55: Cognition in Education. Edited by Jose P. Mestre and Brian H. Ross. Academic Press, 2011.

◆ Interleaving Helps Students Distinguish among Similar Concepts. D. Rohrer in Education- al Psychology Review, Vol. 24, No. 3, pages 355–367; September 2012.

◆ Using Spacing to Enhance Diverse Forms of Learning: Review of Recent Research and Implications for Instruction. S. K. Carpenter, N. J. Cepeda, D. Rohrer, S.H.K. Kang and H. Pashler, ibid., pages 369–378.

◆ When Is Practice Testing Most Effective for Improving the Dura- bility and Efficiency of Student Learning? K. A. Rawson and J. Dunlosky, ibid., pages 419–435.

◆ What Works, What Doesn’t. J. Dunlosky, K. A. Rawson, E. J. Marsh, M. J. Nathan and D. T. Willingham. Scientific American Mind, vol. 24, nr. 4, Sept/Oct 2013 pages 47-53.

◆“Improving Students’ Learning with Effective Learning Techniques: Promising Directions from Cognitive and Educational Psychology,” on which this story for Scientific American Mind is based, at the Association for Psychological Science’s Web site: www.psychologicalscience.org

Traditionally psychologists have attributed negative body image to pictures in the media of unusually thin or beautiful people with whom the rest of us compare our own physique. In June 2011 the American Medical Association released a statement that urged advertisers to stop the use of digitally altered photographs after researchers found links among exposure to mass media, negative body image and disordered eating.

The impact of distorted body image is widespread. Almost half of adolescent girls report being dissatisfied with their appearance, and the number of males reporting serious body image dissatisfaction is also on the rise (although the exact number of males thousands suffer from a clinical body image disturbance such as an eating disorder or body dysmorphic disorder, in which people cannot stop thinking about minor or imaginary “flaws” in their appearance.

Yet the question remains: Given that everyone is exposed to images of presumably perfect bodies, why don’t we all have serious trouble with body image? Research indicates that various biological and environmental factors must come together to create a problem. One of the more recently studied, and perhaps biggest biological contributors, is difficulty with interoception. Interoception informs us of emotions, pain, thirst, hunger and body temperature. People vary on how well they receive such cues. A deficit in this internal sense plays a leading role in the development of anorexia, bulimia and body dysmorphic disorder. Identifying this sensory defect as a major contributor to these ailments suggests new treatments that could speed recovery.

Internal Difficulties

We know whether we are full or hungry, hot or cold, itchy or in pain when receptors in the skin, muscles and internal organs send signals to a region of the brain called the insula. This small pocket of neural tissue is nestled in a deep fold of the brain’s external layer near the ears. It cultivates an awareness of the body’s internal state and, in doing so, plays an important role in self-awareness and emotional experience. Interoceptive data combine in the insula with external information about the body. This region will, for example, connect the sharp pain we experience when touching a hot stove with the red welt that appears on our palm. This integration forms our body image—that is, what we think we look like.

The greater the contribution from interoception as opposed to external, visual cues, the better a person’s body image. A runner with good interoception, say, might focus on the steady thud of her heart and the jolt of her feet against pavement, cues she might use to guide the speed and length of her run. By paying attention to how her body is functioning, the runner feels good about it no matter its exact proportions. A runner with poor interoception, on the other hand, might be thinking about whether onlookers notice the jiggling of her thighs. Because she has little internal input to anchor her sense of self, she can become overly concerned with small visual details, potentially resulting in a diminished body image. Someone with body dysmorphic disorder also lacks this sense of self, inadvertently causing him to focus more on what his nose looks like than how his nose feels on his face.

Distorted body image—known formally as body dysmorphia—can range from mild worries about whether these jeans make one’s bum look fat to an almost delusional misinterpretation of body size and shape as seen in anorexia nervosa and body dysmorphic disorder. People can also have misconceptions in the reverse direction: In a 2010 study almost one in 10 obese adults thought their weight was normal. One explanation for the positive distortion in body shape in these individuals is poor interoception.

In 2004 neuroscientists developed a way to easily and reliably measure this internal experience. Healthy subjects were asked to try to count their heartbeats without taking their pulse while researchers electronically monitored their heart rate. The investigators found that the people whose guesses were closest to their real heart rates also scored highest on other measures of interoceptive awareness, such as questionnaires and brain scans of insula activity.

These heartbeat tests correlated well with how people judged other physiological changes, like feelings from their stomachs. Even those who are good at sensing their internal state do not know they have this talent because they have no way to compare themselves with others. As a result, most people who take the heartbeat test are at least somewhat surprised by their score. (To take the heartbeat test yourself, see the FREEBIE section)

Image Issues

The score does matter. Differences between women in interoceptive skill predict their level of body satisfaction. In a study last year, 214 college-age females were given tests for psychological problems ranging from social anxiety to disordered eating. They found that those who scored lower on measures of interoceptive ability had not only higher levels of body dissatisfaction but also more symptoms of eating disorders than those who were more in tune with their body.

People with anorexia have problems interpreting hunger and fullness cues. Someone with damaged interoception may not be able to physically sense her weight loss and so persists in thinking her body weight is normal or high even as she becomes emaciated. In anorexia patients, these difficulties extend to all areas of interoception: when they perform the heartbeat task, they typically do worse than people without the disorder.

In a study published in 2008 it was found that 28 anorexic women were about 68 percent accurate in sensing their heart rate compared with a 77 percent accuracy rate for women who did not have an eating disorder. This result represents a significant difference in interoceptive ability. Besides being worse at interoception, the anorexic women also had more psychological problems, such as depression and anxiety, lower body weights and significantly higher body dissatisfaction. (Virtually all the imaging studies done in anorexia patients have involved women because of the low number of males diagnosed with the illness.)

Underlying the interoceptive issues of anorexic individuals may be an unresponsive insula. In a study published in 2005 functional MRI was used to scan the brains, at rest, of 12 women who had recovered from anorexia nervosa. They found diminished blood flow—suggesting lower activation—in the insula of these women relative to 11 control subjects who had never had anorexia. An fMRI study published in 2003 had shown similar results. Both studies suggest that recovered anorexics are relatively slow to process interoceptive information, a bottleneck that likely leads to less input to their brain about their body and may complicate the recovery process.

Outside Influences

In addition to interpreting internal cues at rest, the insula typically responds with a burst of activity when a person is looking at a picture of herself. When normal, healthy women see photographs of themselves, blood rushes to the insula, suggesting that the picture enhances a person’s experience of what it is like to be inside her own body.

In anorexic women, however, the insula remains mute, even when prodded by such images. In a study published in 2008, researchers asked 10 anorexic women and 10 other females to view photographs of themselves and of others while in an MRI machine. Although seeing images of themselves caused a boost in insula activity in the healthy women, no such increase in activity appeared in the anorexic women (see MRI images below).

This finding hints that anorexics lack the ability to link external cues about their appearance to internal knowledge of their body, which was likely minimal in the first place. (The differences disappeared when the women looked at pictures of other people: in both groups, the insula was quiet.)

Compounding the problem, deficiencies in interoception may make your body image more vulnerable to other visual influences. In a 2011 study 46 female college students were tested using an unusual type of visual cue: a rubber hand. In what is known as the rubber hand illusion, a person can be made to feel as if a rubber hand is part of his body by having him place both hands on a table and blocking his view of the left hand with a cardboard divider. Immediately to the right of the divider, an experimenter places a lifelike rubber hand. Then he or she gently strokes both the person’s left hand and the rubber one with a small paintbrush. After a minute or two, many people begin to believe that the rubber hand is their real hand. Amazingly, the temperature of the left hand also drops significantly, suggesting that the brain loses ownership of the real left hand and gains ownership of the rubber hand.

Based on the results of the heartbeat test, the women were split into two groups: those with high scores—the group average was better than 80 percent—and those whose scores were below 50 percent. They found that the females with lower bodily awareness could more easily be fooled into thinking that a rubber hand was part of their body. Similarly, researchers think media images of thin women will have an outsize effect on those who lack internal awareness. People with good interoception, with their solid sense of themselves, would be less affected by seeing someone skinnier or, by some standards, more attractive than they are.

People with body dysmorphic disorder may have an additional perceptual problem. Evidence suggests they have visual-processing abnormalities that distort what they see. This distortion probably combines with low interoception to create a particularly poor body image.

Those who lack a keen awareness of their internal state also seem to be easily swayed by the opinions of others. They may evaluate their goals and attributes based on how they think others perceive them rather than by their own standards. In a study in 2004 scientists asked adult women with body dysmorphic disorder to recall specific memories from childhood. The researchers found that these women were significantly more likely to relate personal experiences as if they were happening to someone else. Instead of describing an event using a first-person perspective (for instance, “I saw …”), the patients with body dysmorphic disorder told the story as if they were a narrator in a novel (“this happened …”). Building better interoceptive awareness, then, could not only improve body image, it could also bolster a fragile sense of self.

Minding the Body

One way to increase your internal sense is to practice mindfulness, a mental mode characterized by attending fully to the present moment without elaboration or judgment. In numerous studies in the past decade researchers have found that incorporating mindfulness training into cognitive-behaviour therapy and other treatments for eating disorders and body dysmorphic disorder has diminished symptoms and enhanced quality of life. Training people to closely heed their current, ongoing physical sensations may improve their interoception, scientists theorize.

Recent studies have tested yoga as a potential therapy for eating disorders. Certain forms of yoga, such as hatha or vinyasa yoga, encourage the participant to focus on both their breathing and the different bodily sensations produced by each pose—practices central to mindfulness.

In 2010 clinical psychologists assigned 27 adolescents receiving outpatient eating disorder treatment to eight weekly hour-long yoga sessions. The researchers hoped that by focusing their attention on the yoga poses and their own body, the adolescents would decrease their obsessions with food and weight.

The strategy seemed to work. At the start of treatment, these adolescents were so disconnected from their body that they had trouble balancing on one foot. After eight weeks of yoga, the teens had gained enough interoceptive skills to easily find their balance. They also showed greater improvements in all areas of eating disorder psychopathology, including body dysmorphia, than did 27 similarly afflicted youth who did not take yoga. It appears that yoga helps to give the young people a way to be more in tune with their body.

References:

Functional Neuroimaging in Early-Onset Anorexia Nervosa. B. Lask et al. in International Journal of Eating Disorders, Vol. 37, S49–S51; 2005. Discussion on pages S87–S89.

Randomized Controlled Clinical Trial of Yoga in the Treatment of Eating Disorders. T. R. Carei, A. L. Fyfe-Johnson, C. C. Breuner and M. A. Brown in Journal of Adolescent Health, Vol. 46, No. 4, pages 346–351; April 2010.

Just a Heartbeat Away from One’s Body: Interoceptive Sensitivity Predicts Malleability of Body-Representations. M. Tsakiris, A. Tajadura-Jiménez and M. Costantini in Proceedings of the Royal Society B, Vol. 278, pages 2470–2476; August 22, 2011.

Inside the Wrong Body. C. Arnold. Scientific American Mind (May/June 2012), Vol. 23, pages 36-41.

The Dalai Lama is reknown for his interest in neuroscience. When I stumbled across this very recent article by top neuroscientist Christof Koch about his experience with the Dalai Lama, I knew that I had to share this with you all. So here it is, cut & pasted without apology straight into my newsletter :=)

“Knowledge can be communicated, but not wisdom. One can find it, live it, do wonders through it, but one cannot communicate and teach it.”

This line from Herman Hesse’s 1922 novel Siddhartha came unbidden to me during a recent weeklong visit to Drepung Monastery in southern India. His Holiness the Dalai Lama had invited the U.S.-based Mind and Life Institute to familiarize the Tibetan Buddhist monastic community living in exile in India with modern science. About a dozen of us—physicists, psychologists, brain scientists and clinicians, leavened by a French philosopher—introduced quantum mechanics, neuroscience, consciousness and various clinical aspects of meditative practices to a few thousand Buddhist monks and nuns. As we lectured, we were quizzed, probed and gently made fun of by His Holiness, who sat beside us [see photograph; Christof Koch is the suited man by the Mac laptop]. We learned as much from him and his inner circle—such as from his translator, Tibetan Jinpa Thupten, who has a doctor- ate in philosophy from the University of Cambridge, and from the French monk Matthieu Ricard, who holds a Ph.D. in molecular biology from the Pasteur Institute in Paris—as they and their brethren from us.

What passed between these representatives of two distinct intellectual modes of thinking about the world were facts, data—knowledge. That is, knowledge about the more than two-millennia-old Eastern tradition of investigating the mind from the inside, from an interior, subjective point of view, and the much more recent insights provided by empirical Western ways to probe the brain and its behavior using a third-person, reductionist framework. What the former brings to the table are scores of meditation techniques to develop mindfulness, concentration, insight, serenity, wisdom and, it is hoped, in the end, enlightenment. These revolve around a daily practice of quiet yet alert sitting and letting the mind settle before embarking on a specific program, such as “focused attention” or the objectless practice of generating a state of “unconditional loving-kindness and compassion.” After years of daily contemplative exercise—nothing comes easily in meditation—practitioners can achieve considerable control over their mind.

Twelve years of schooling, four years of college and an even longer time spent in advanced graduate training fail to familiarize our future doctors, soldiers, en- gineers, scientists, accountants and politicians with such techniques. Western universities do not teach methods to enable the developing or the mature mind to become quiet and to focus its considerable powers on a single object, event or train of thought. There is no introductory class on “Focusing the Mind.” And this is to our loss!

From introspection, we are all familiar with the mental clutter, the chatter that makes up our daily life. It is a rapid fire of free associations, of jumping from one image, speech fragment or memory to the next. Late-night lucubrations are particularly prone to such erratic zigzagging. Focusing on a single line of argument or thought requires deliberate, laborious and conscious effort from which we flee. We prefer to be distracted by external stimuli, conversations, radio, television or newspapers. Desperate not to be left alone within our mind, to avoid having to think, we turn to our constant electronic companions to check for in-coming messages.

Yet here we had His Holiness, a 77-year-old man, who sat during six days, ramrod straight for hours on end, his legs tucked under his body, attentively following our arcane scholarly arguments. I have never experienced a single man, and an entire community, who appeared so open, so content, so happy, constantly smiling, yet so humble, as these monks who, by First World standards, live a life of poverty, deprived of most of the things we believe are necessary to live a fully realized life. Their secret appears to be mind control.

Among the more extreme cases of mind control is the self-immolation of the Vietnamese Buddhist monk Thich Quang Duc in 1963 to protest the repressive regime in South Vietnam. What was so singular about this event, captured in haunting photographs that are among the most readily recognized images of the 20th century, was the calm and deliberate nature of his heroic act. While burning to death, Duc remained throughout in the meditative lotus position. He never moved a muscle or uttered a sound, as the flames consumed him and his corpse finally toppled over.

I am filled with utter bewilderment in the face of this singular event and would have found it difficult to accept as real, were it not captured in the testimony of hundreds of onlookers, including jaundiced journalists with their cameras.

Brain Basis of Mind Control

A step toward a brain-based explanation of this extraordinary phenomenon comes from a recent scanning experiment by Fadel Zeidan, Robert C. Coghill and their colleagues at the Wake Forest School of Medicine. Fifteen volunteers were recruited to lie in a scanner while a small metal plate was attached to their right calf. As its temperature varied from pleasant (near body temperature) to painful (49 degrees Celsius), subjects had to rate both pain intensity and pain unpleasantness of the noxious stimulus. Predictably, the hot probe triggered increased hemodynamic activity in structures that are known to be involved in pain processing, such as the primary and secondary somatosensory cortices that represent the leg, as well as more frontal structures, the anterior cingulate cortex and the insula. Subsequently, the volunteers underwent four days of 20 minutes’ daily practice of mindfulness meditation involving focused attention or the Buddhist mind-calming practice called shamatha. In the latter, the practitioner focuses attention on the changing sensations of her breath, noting thoughts, pictures and memories as they arise from their inner source, but without any emotional engagement. This exercise frees her to quickly disengage from them to return attention to monitoring her breathing.

Practicing mindfulness during the noxious stimulation reduced the unpleasantness of the pain by a whopping 57 percent and its intensity by 40 percent. And this after only minimal training (four times the 20 minutes). Of course, it is a far cry from attenuating the unthinkable agony of burning to death, but still. Mindfulness exerts its effect by promoting a sense of detachment and by reducing the subjectively experienced saliency of the heated metal plate. Yet how does it work in the brain?

Pain-related activity in the primary and secondary somatosensory cortices was reduced by the meditation. Those subjects who experienced the greatest reduction in the intensity of their pain had the largest increase of activity in their right insula and both sides of their anterior cingulate cortices. Subjects with the greatest reduction of the unpleasantness of the pain—which is what most people care about— exhibited the greatest activation of regions in the orbitofrontal cortex and the largest reduction in the thalamus (gating the incoming sensory information).

Think of mindfulness, think of all meditations, as mental skills to control emotions and to shape the impact that external events, such as sight, sound or heat, have on the sensory brain. Select prefrontal regions in the practitioner’s brain reach all the way down to the thalamus to reduce the flood of incoming information from the periphery, leading to a lessening of the pain. These skills to steer the mind are not magical, otherworldly or transcendental. They can be learned by sufficiently intensive practice. The only question is whether our instruments are always sufficiently sensitive to pick up their footprints in the brain.

In 2008 Richard J. Davidson and his group at the University of Wisconsin– Madison published a classic study with the active participation of Ricard and other Buddhist monks. The cognitive scientists fitted skullcaps with 128 electro-encephalographic (EEG) electrodes to the heads of eight long-term Buddhist practitioners and 10 student volunteers. The former were asked to attain a state of “unconditional loving-kindness and compassion” (a form of meditation that does not focus on a single object and is sometimes referred to as “pure compassion”), whereas the volunteers thought about somebody he or she deeply cared about and then tried to generalize these feelings to all sentient beings.

The onset of meditation in the monks coincided with an increase in high- frequency EEG electrical activity in the so-called gamma band (spanning 25 to 42 oscillations a second), which was synchronized across the frontal and parietal cortices. Such activity is thought to be the hallmark of highly active and spatially dispersed groups of neurons, typically associated with focusing attention. Indeed, gamma activity in these monks is the largest seen in nonpathological conditions and 30 times greater than in the novices. The more years the monks had been practicing meditation, the stronger the (normalized) power in the gamma band.

More important, even when the monks were not meditating, but simply quietly resting, their baseline brain activity was distinct from that of the students. That is, these techniques, practiced by Buddhists for millennia to quiet, focus and expand the mind—the interior aspect of the brain—had changed the brain that is the exterior aspect of the mind. And the more training they had, the bigger the effect.

Yet knowing about meditation and its effect on the brain is not the same as benefiting from it and not the same as achieving wisdom. So just like the young Siddhartha in Hesse’s novel, I left the monastic community richer in knowledge about a different way to look at the world but continuing to strive.

It is quite incredible that even though scientists have been studying strokes for decades, the only intervention available is a drug that breaks up blood clots, and only a small number of patients benefit from it. Brain damage is unfortunately inevitable in most cases. However, new research in rat studies has shown that they were saved from brain damage after a stroke when neuroscientists simply touched their whiskers or played sounds in their ear.

The new research offers the tantalising possibility of a low-tech, inexpensive treatment that could be dispensed immediately, anywhere, and by anyone. Although translating these interventions into human treatments means overcoming significant hurdles, the revolutionary finding has invigorated a field fraught with dead ends and lackluster results.

Stumped for Treatments

A stroke happens when a sudden loss of blood causes a part of the brain to stop working. The blood shortage may arise from either of two main causes: a blood clot or a hemorrhage. More than three quarters of strokes are clot-based or ischemic; the rest are hemorrhagic, in which a blood vessel bursts inside the brain. In both types, cells downstream of the clot or eruption are cut off from the vital supply of nutrients and oxygen.

The lack of treatments for stroke certainly is not for lack of research efforts. More than 1,000 compounds have been studied in animal models, but the dozens that have gone on to human clinical trials have all failed except one. Tissue plasminogen activator (tPA), the only treatment for stroke approved by the Food and Drug Administration, attempts to unblock a clogged blood vessel by breaking up the clot. It must be given in the first couple of hours after stroke, turning treatment into a game of beat the clock. Although tPA is potentially lifesaving for someone having an ischemic stroke, the clot-busting drug would spell disaster for someone with a hemorrhagic stroke, where clots must form to stop the bleeding. To make sure the wrong people do not get tPA, patients must undergo a brain scan before receiving the medication—a time-consuming step that delays treatment, disqualifying most patients.

Clot busters are one of the two main types of treatments that researchers have attempted to develop over the years. The other is neuroprotective agents, which employ a wide variety of brain-saving strategies, including dampening electrical activity and halting signaling molecules within brain cells. The wide range of approaches speaks to the complexity of the processes at work in the stroke-damaged and recovering brain. When brain cells go too long without access to oxygen-rich blood, catastrophe ensues: the balance of charged particles inside and outside cells is upset, a harmful amount of calcium flows into cells, and electrical activity runs rampant, leading to a dangerous state called excitotoxicity. Next, cell membranes break down, and free radicals—reactive particles that damage cells and DNA—build up. These events trigger programmed cell death, during which genetic material and cellular structures are destroyed. Even surviving cells surrounding the affected area are in danger; the sudden flood of oxygen and nutrients that follows a successful dissolution of a clot can further skew the delicate ecosystem of the brain and spread the damage wider.

Researchers have attempted to develop neuroprotective drugs aimed at certain elements of these destructive cascades, with little success thus far. Still, experts are hopeful; early failures could have been because of poor guesses about dosage or time frames. Efforts aimed at neuroprotection continue today; for example, a clinical trial called FastMag, headed by clinical stroke expert Jeffrey Saver of U.C.L.A., is in its final stages. In this trial, ambulance personnel give patients an injection of magnesium ions in an attempt to quell the brain’s hyper-excitability immediately after a stroke.

Stroke experts agree that the best form of neuroprotection is to restore blood flow to the area cut off by the stroke—and fast. To that end, an epiphany of sorts hit researchers when they realised that blood vessels in the brain look more like a connected matrix of loops than like a tree with branches. Vessel structure is more like the streets of a large busy city: when there is a lorry parked in the middle of a road so that you can’t get through, then you try to take another road. Figuring out how to get blood rerouted through these existing networks in the brain could very well be the key to keeping cells alive—but until now, researchers had no idea how to harness this network.

Recruiting Nearby Blood Vessels

Serendipitously, neuroscientists at U.C. Irvine discovered that the brain’s blood vessel supply might be at the beck and call of the very neurons it serves, providing a built-in defense against stroke. Five years ago Frostig, who studies neuroplasticity at U.C. Irvine, had set out to test whether rats that were allowed to actively explore a natural environment might recover better after a stroke. ‘Enriched environments’ or ‘enriched experiences’ have been found to improve brain health and function in many settings, particularly in rehabilitation. To mimic the occurrence of a stroke, Frostig and his team cut the middle cerebral artery (MCA), a major blood supply route, in an anesthetised rat. Immediately after cutting the MCA, they wanted to get a baseline measure of stroke-damaged brain activity, so they used a mechanical device to wiggle one of the rat’s whiskers and simultaneously gauged the activity of the corresponding neurons in the cortex. They expected this baseline activity to be utterly destroyed by the stroke, and they hoped it might improve over time as the rat recovered.

Instead, during the stroke and a day later, the neurons looked and acted completely normal. Frostig was shocked; even the most promising therapeutic agents typically provide just marginal defense against stroke in lab animals. Only half-joking, he asked postdoctoral fellow Christopher Lay whether he was sure he had cut the artery. But after the result held up in 30 animals, they realised that something important was going on. The neurons were completely protected. Eventually the researchers concluded that by stimulating that single whisker immediately after stroke, they had prevented any stroke-related brain damage.

Once Frostig and his team were convinced their results were real, they looked for signs of damage, and they looked hard. They first reported in 2010 that they could find no difference between the brains of rats with a wiggled whisker and control rats that had no interruption to their blood supply. A staining technique revealed no damage; brain imaging showed functional blood flow to the affected area; even direct recordings of the neurons activated by whisker movement showed the area was electrically active and healthy. And the animals behaved normally on waking. But the rats were protected only when they were stimulated within an hour or two of the stroke—any later, and they actually suffered worse damage than unstimulated rats.

The time window seems to be critical. In subsequent research published in 2011, it was confirmed that timing—not duration or pattern—of stimulation is key. Past the three-hour mark, stimulation does more harm than good. It is not yet known what is the underlying cause of this three-hour switch. Although other animal studies have revealed that some molecules are destructive early in an attack but required for remodeling and recovery at later stages, many questions remain.

So why does wiggling a whisker save the brain? Frostig suspected that the sensory experience activates the very cortex that was deprived of blood flow. The key issue is neuronal activity. This flurry of activity and its attendant demand for oxygen recruited an alternative blood supply. Along with two other major arteries, the MCA supplies blood to the cerebral cortex, its trunk splitting into progressively smaller branches. At their tips, the fine branches of these vascular trees interconnect with one another, forming a vast network. Blood does not normally flow through these loops, but Frostig’s investigation using advanced brain imaging showed that after the stroke the rats’ neuronal activity indeed recruited blood via these alternative routes. When Frostig sealed off the MCA network’s collateral branches—in addition to cutting their supply trunk—no amount of stimulation could save the cortex.

Researchers do not yet know how, exactly, neuronal activity evokes the change in blood flow. Current research is investigating non-neuronal cells called astrocytes, which are closely coupled to blood vessels in the brain and seem to be involved in signaling for oxygen and nutrients. In the meantime, Frostig and his colleagues are investigating whether other types of sensory input can protect the brain as well. He has more recently found that auditory stimuli—bursts of white noise—also protected from stroke, though not as completely as whisker stimulation. This is probably because whereas whisker stimulation “tickles” much of the blood-starved cortex, sound activates only the auditory cortex at the edge of the affected area.

A Much Needed Breakthrough

Moving from rodents to humans is a challenge for any therapy, and experts, including Frostig, are cautious about predicting a future of sensory-stimulated recovery for people. But hope-starved stroke researchers cannot help but be enthusiastic. The beauty is that it’s cheap and nontoxic! And the treatment remains effective even as Frostig’s group has systematically expanded testing to address some of the differences between the response of humans and lab rats. The team has made sure that awake and anesthetised animals are protected because an estimated 70 percent of strokes occur in awake people. In his 2012 paper, Frostig’s team showed that elderly rats were protected as well as the juvenile animals commonly used in lab research; in humans, age is the number-one risk factor for stroke. Furthermore, the protection held up in rats that got sensory stimulation by exploring their environment and whose whiskers had been removed— a good thing for whiskerless humans.

Most important, by studying ischemic attack in the territory of the brain supplied by the MCA, Frostig is investigating the conditions that account for the vast majority of human strokes.

One big challenge for this treatment to overcome is that humans do not have an exact analogue to the barrel cortex, the area in a rat’s brain dedicated to sensing whisker movements. This area is huge in rats; in humans, the closest equivalent would be the cortical real estate dedicated to the fingers and lips. Because the relative size of our sensory cortex is much smaller than that of rats, Frostig predicts sensory stimulation of more than one type might be required. “Sing to them, stroke their hands, their face—while you’re calling the ambulance,” Frostig says. Engaging someone in whatever stimulation possible might increase the chance of activating—and thereby protecting—more cortex. As for that ambulance ride, which itself is noisy, it alone may not help, because ambulance personnel do not necessarily make a point of actively engaging a patient. Taking sensory stimulation to that next level, such as by caressing the patient’s face and hands, might make all the difference.

Frostig’s work shows promise for circumventing some of the other inherent problems in stroke treatment, too. Sensory stimulation is unlikely to be derimental to someone with a hemorrhagic stroke, eliminating the need for time-consuming brain scans. If the treatment indeed reroutes blood flow, it could aid in the delivery of therapeutic drugs, including tPA—a major challenge in stroke treatment today. And the new finding underscores the importance of timing. People who miss the critical window for treatment, for instance, because they wake up from a night’s sleep having had a stroke, might benefit from little or no stimulation at all—no sirens wailing, no medical team barking orders, no constant barrage of questions and tests.

Human trials based on Frostig’s work are still far away—first the idea needs to be tested in larger animals such as monkeys or pigs. It could be years before we know if sensory stimulation can do for people even a fraction of the good it does for rats. But as the quest continues for clot busters and neuroprotectants, for new techniques and technology, stroke experts across the board agree that fresh ideas are welcome.

So if you find your in a situation with someone who is having a stroke, go ahead and sing to them, caress their hands and face; if nothing else, they will feel comforted at a scary time. And you might just save their brain.

See you again in July!

References:

◆ Update of the Stroke Therapy Academic Industry Roundtable Pre­ clinical Recommendations. Marc Fisher et al. in Stroke, Vol. 40, No. 6, pages 2244–2250; June 2009.

◆ Understanding and Augmenting Collateral Blood Flow during Ischemic Stroke. Gomathi Ramakrishnan, Glenn A. Armitage and Ian R. Winship in Acute Ischemic Stroke. Edited by Julio César García Rodriguez. InTech, 2012.

◆ A Rat’s Whiskers Point the Way toward a Novel Stimulus­Dependent, Protective Stroke Therapy. Ron D. Frostig, Christopher C. Lay and Melissa F. Davis in Neuroscientist. Published online October 9, 2012.

◆ For the warning signs and symptoms of stroke, see the American Stroke Association Web site: www.strokeassociation.org/STROKEORG/ WarningSigns/Stroke­Warning­Signs_UCM_308528_SubHomePage.jsp

◆ A Magic Touch for Stroke Prevention? S. Sutherland in Scientific American Mind, Vol. 24, number 3, pages 48-53.

Imagine you get nine hours of sleep every night, squeeze in long naps whenever you can, and yet every waking hour is a blur of exhaustion, poor focus and longing for the next time your head will hit the pillow. That is the reality for people with primary hypersomnia, a poorly understood, rare condition of constant sleepiness and tiredness.

The theory in sleep science has been that unexplained sleepiness is caused by underactive brain regions involved in wakefulness and attention. This view has done little to provide relief for many of the chronically tired. Yet the opposite hypothesis—that the body might be producing a natural brake or sedative—has been controversial. Now scientists at Emory University have found just such a sedative in patients with primary hypersomnia, providing hope for the weary and perhaps even pointing to a new type of sleep-aid drug.

The researchers discovered the sleep-promoting substance in the patients’ cerebrospinal fluid, the watery liquid that cushions the brain and surrounds the spinal cord. In a study appearing in Science Translational Medicine last November, the researchers demonstrated that the compound enhances the activity of the same signaling pathway in the brain that is spurred on by sedatives such as the commonly prescribed benzodiazepines Valium and Ambien. The pathway involves gamma-aminobutyric acid (GABA), which is a neurotransmitter that acts a brake on attention and focus.

The researchers took spinal fluid from 32 patients with primary hypersomnia and applied it to human cells while measuring their electrical activity. They found the spinal fluid increased GABA receptor activity dramatically by some 84 percent, when GABA was also present (as it is in the brain). Spinal fluid from unaffected individuals enhanced GABA receptor activity, too, though to a lesser extent. There the boost was closer to 36 percent—similar to the effect produced by patients’ spinal samples after researchers removed the natural sedative.

The compound’s chemical identity remains a mystery; the researchers have determined that it is probably a small protein (called a peptide). Future work will focus on identifying and perhaps even synthesizing the substance, to act as a sleep aid for people with insomnia.

For the permanently sleepy, this recent work offers hope. Because their internal sedative acts in the brain like Valium, the investigators reasoned that its action could be blocked by flumazenil, a drug given intravenously to treat benzodiazepine overdoses.

In seven patients suffering from hypersomnia, flumazenil did restore alertness and reaction times for several minutes to a few hours, depending on the dose. For one of these patients—a woman who has managed to obtain an ongoing supply of the drug in tablet and cream forms—that relief has lasted four years.

Getting enough flumazenil to treat multiple individuals with hypersomnia may be tricky—the entire North American supply would be enough for only four hypersomniacs at the doses likely needed to maintain alertness all day, every day. Even so, Emory researchers have begun initial trials exploring the possibility of using flumazenil, or another drug similar to it, to awaken those people who have to live with the ‘nightmare’ of internal sedation.

References:

B. Rye et al.. Modulation of Vigilance in the Primary Hypersomnias by Endogenous Enhancement of GABA_A Receptors. Science Translational Medicine 2012, volume 4, number 161, 161ra151

A. Anderson. An Internal Sedative. Scientific American Mind 2013, volume 24, number 1, 12-13.

More than half the world’s population now lives in a large city, and by 2050 that figure will very likely jump to two thirds. China’s megacities in particular are fueling the trend, with more than 10 million new residents every year. Historically, urbanisation has brought about stupendous changes—the Renaissance, the industrial revolution, globalisation. Yet this urban migration represents one of the most dramatic environmental shifts human beings have ever undertaken. So we might be tempted to ask: How are we adapting to our new surroundings?

At first glance, trading green fields for grey grids would seem to be a trade up. City slickers have, on average, more money, better food and greater access to health care than country folk. On the flip side, though, recent studies indicate that memory and attention can suffer in urban environments, and psychologists have long known that city life takes an emotional toll. Urbanites are more likely to suffer from anxiety and depression, and the risk of schizophrenia increases dramatically among people raised in a city. Some researchers have calculated that children born in cities face twice, if not three times, the risk of developing a serious emotional disorder as compared with their rural and suburban peers.

These statistics may not surprise harried rush-hour commuters, but they are also not easily explained. Epidemiologists have ruled out the most obvious answers—namely, that people at risk for developing emotional disorders are more drawn to urban areas. Instead certain aspects of metropolitan life appear to incline the brain toward mental illness. A number of possible culprits are now under investigation, among them noise, pollution and social pressure, in both the form of greater competition and weaker community ties.

Several inquiries suggest that this last factor, social stress, is especially harmful. Research at the Central Institute of Mental Health in Mannheim, Germany, corroborates this view and provides the first neurobiological mechanism to explain it. In a series of studies, evidence has found that the social strain of urban living engages specific stress circuits in the brain—circuits known to go wrong in mood disorders and other mental illnesses. Perhaps by understanding this mechanism and its role in the development of psychiatric conditions, ways can be found to intervene and make cities more livable.

Stress in the City

Many studies have confirmed the link between social strain and mental illness. In 2010 Stanley Zammit and his colleagues at Cardiff University in Wales traced the origins of schizophrenia in 200,000 individuals in Sweden. They found an array of contributing factors, all of which were increasingly potent in more urban environments. In general, though, people who perceived themselves as isolated—immigrants, for example—were at significantly greater risk. Such research is invaluable but relies on a rough measurement: the frequency of clinically diagnosed psychiatric patients. To look for more subtle connections between the pressure of city life and emotional instability, magnetic resonance imaging (MRI) has been used.

In 2011, the brain activity of 32 German college students, who hailed from big cities, towns or countryside was measured. As the recruits performed a series of brainteasers, the researchers deliberately stressed them out. For example, while inside the scanner, each volunteer saw a false performance meter, which indicated that they were doing poorly compared with everyone else. At the same time, one of the researchers urged them to try harder otherwise they were told that they would ruin the experiment. It worked. Not only did was an elevated heart rate, blood pressure and level of stress hormones in the participants detected, but after the test—when they were told what the scientists had done—they confirmed that they had indeed felt pressured.

As expected, this stressful experience activated many areas in the brain. Astonishingly, though, one particular region, the amygdala, whose activity under pressure exactly matched the subjects’ house address: the more urban their home environment, the more engaged their amygdala became. This cherry-size structure, deep within the temporal lobe, serves as a danger sensor of sorts, prompting the “fight or flight” response. It also modulates emotions such as fear. In this study, the amygdala seemed almost impervious to stress among villagers and was only moderately active among those from small towns. For big city residents, stress kicked it into overdrive.

The German scientists had not expected such a strong correlation, and so they repeated the experiment, placing 70 additional test subjects under slightly different stress conditions. Again, they saw the same pattern. In each experiment, they could readily identify city residents by brain scan alone: urban life had marked all of them with telltale hyperactivity in the amygdala. This finding revealed at least one way in which city stress can lead to mental illness. An amygdala in high gear is also observed in patients suffering from depression and anxiety. Not all urbanites succumb to mood disorders, of course, but the researchers concluded that chronic overstimulation of this brain region puts some people at a higher risk.

The very same mechanism may play at least a small role in prompting violent behaviour. Violence is not a psychiatric diagnosis per se; it results from an exceedingly complex interplay of factors. Even so, data from the U.S., Germany and elsewhere confirm that violence is a bigger problem in cities, and several lines of inquiry link violent behaviour with overstimulation of the amygdala.

Urban Upbringing

The German researchers wanted to follow up on another important observation—namely, the increased risk for schizophrenia in people born and raised in cities. They analysed the same subjects described above and quantified their early urban exposure using a simple score: they assigned three points for each year they had lived in a city as a child, two for each year in a town and one for each year of country living. Again, they found one specific brain region—the perigenual anterior cingulate cortex (pACC)—whose activity levels under stress reflected the city score. Subjects who spent the most time growing up in cities showed the highest levels of pACC activity under pressure. A second experimental group of 70 students showed the same correlation between pACC activation and urban upbringing.

This finding was not a total surprise. The pACC and the amygdala are closely interconnected. Studies indicate that the pACC serves to inhibit activity in the amygdala. If the pACC is damaged through chronic stimulation during a city upbringing, it might then fail to quell an overactive amygdala in an urban adult. If the same adult were sheltered from social strain, this deficit might never surface. Infact, giving brainteasers to a control group, without any pressure, no association was found between childhood environment and activity in the amygdala or pACC.

Additional research supports this idea. Various researchers—including Tsutomu Takahashi of Toyama University in Japan—have found structural changes in the pACC in patients with schizophrenia. Notably, these alterations also manifest among those who are at an increased genetic risk of the disease developing, before they exhibit any psychiatric symptoms.

Lean on Me

All these studies reveal that the longer a person lives in a city, the less communication occurs between their amygdala and pACC. Genes and other factors then steer city dwellers closer to developing schizophrenia, anxiety, depression or violent tendencies. Fortunately, scientists have found mechanisms that strengthen feedback between these two brain regions. In 2011 Lisa Feldman Barrett and her colleagues at Massachusetts General Hospital reported that the volume of the amygdala increases with the size of a person’s circle of friends. It has also been found that the hormone vasopressin—which, among other roles, is released during moments of bonding—reduces activity in areas of the cingulate cortex, including the pACC, and boosts feedback to the amygdala.

These studies highlight the well-documented fact that a close network of friends and family can insulate us from the most damaging effects of stress, but this is not the whole story. A lack of green space, noise and other environmental factors may also contribute to pACC and amygdala dysfunction. Such research could have far-reaching consequences: Almost a third of schizophrenia cases might be avoided if more people were born in a rural setting. Herein lies a paradox: we cannot act on this insight without urbanizing the countryside. But we can try to design our cities so that they promote emotional well-being. In this way, we might take aim at the real goal of psychiatry, which is to prevent serious emotional disorders, not just treat them.

References:

5-HTTLPR Polymorphism Impacts Human Cingulate-Amygdala Interactions: A Genetic Susceptibility Mechanism for Depression. Lukas Pezawas, Andreas Meyer-Lindenberg, Emily M. Drabant, Beth A. Verchinski, Karen E. Munoz, Bhaskar S. Kolachana, Michael F. Egan, Venkata S. Mattay, Ahmad R. Haririand Daniel R. Weinberger in Nature Neuroscience, Vol. 8, No. 6, pages 828–834; June 2005.

City Living and Urban Upbringing Affect Neural Social Stress Processing in Humans. Florian Lederbogen, Peter Kirsch, Leila Haddad, Fabian Streit, Heike Tost, Philipp Schuch, Stefan Wüst, Jens C. Pruessner, Marcella Rietschel, Michael Deuschle and Andreas Meyer-Lindenberg in Nature, Vol. 474, pages 498–501; June 23, 2011.

The Stress of Crowds. Alla Katsnelson in Scientific American, Vol. 305, No. 3, page 18; September 2011.

Neural Mechanisms of Social Risk for Psychiatric Disorders. Andreas Meyer-Lindenberg and Heike Tost in Nature Neuroscience, Vol. 15, No. 5, pages 663–668; May 2012.

Mounting Evidence Shows How City Living Can Harm Our Mental Health. Andreas Meyer-Lindenberg in Scientific American Mind Vol. 24, number 1, pages 59-61; March/April 2013.