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Easing Brain Fatigue With a Walk in the Park
Scientists have known for some time that the human brain’s ability to stay calm and focused is limited and can be overwhelmed by the constant noise and hectic, jangling demands of city living, sometimes resulting in a condition informally known as brain fatigue.
With brain fatigue, you are easily distracted, forgetful and mentally flighty — or, in other words, me.
But an innovative new study from Scotland suggests that you can ease brain fatigue simply by strolling through a leafy park.
The idea that visiting green spaces like parks or tree-filled plazas lessens stress and improves concentration is not new. Researchers have long theorized that green spaces are calming, requiring less of our so-called directed mental attention than busy, urban streets do. Instead, natural settings invoke “soft fascination,” a beguiling term for quiet contemplation, during which directed attention is barely called upon and the brain can reset those overstretched resources and reduce mental fatigue.
But this theory, while agreeable, has been difficult to put to the test. Previous studies have found that people who live near trees and parks have lower levels of cortisol, a stress hormone, in their saliva than those who live primarily amid concrete, and that children with attention deficits tend to concentrate and perform better on cognitive tests after walking through parks or arboretums. More directly, scientists have brought volunteers into a lab, attached electrodes to their heads and shown them photographs of natural or urban scenes, and found that the brain wave readouts show that the volunteers are more calm and meditative when they view the natural scenes.
But it had not been possible to study the brains of people while they were actually outside, moving through the city and the parks. Or it wasn’t, until the recent development of a lightweight, portable version of the electroencephalogram, a technology that studies brain wave patterns.
For the new study, published this month in The British Journal of Sports Medicine, researchers at Heriot-Watt University in Edinburgh and the University of Edinburgh attached these new, portable EEGs to the scalps of 12 healthy young adults. The electrodes, hidden unobtrusively beneath an ordinary looking fabric cap, sent brain wave readings wirelessly to a laptop carried in a backpack by each volunteer.
The researchers, who had been studying the cognitive impacts of green spaces for some time, then sent each volunteer out on a short walk of about a mile and half that wound through three different sections of Edinburgh.
The first half mile or so took walkers through an older, historic shopping district, with fine, old buildings and plenty of pedestrians on the sidewalk, but only light vehicle traffic.
The walkers then moved onto a path that led through a park-like setting for another half mile.
Finally, they ended their walk strolling through a busy, commercial district, with heavy automobile traffic and concrete buildings.
The walkers had been told to move at their own speed, not to rush or dawdle. Most finished the walk in about 25 minutes.
Throughout that time, the portable EEGs on their heads continued to feed information about brain wave patterns to the laptops they carried.
Afterward, the researchers compared the read-outs, looking for wave patterns that they felt were related to measures of frustration, directed attention (which they called “engagement”), mental arousal and meditativeness or calm.
What they found confirmed the idea that green spaces lessen brain fatigue.
When the volunteers made their way through the urbanized, busy areas, particularly the heavily trafficked commercial district at the end of their walk, their brain wave patterns consistently showed that they were more aroused, attentive and frustrated than when they walked through the parkland, where brain-wave readings became more meditative.
While traveling through the park, the walkers were mentally quieter.
Which is not to say that they weren’t paying attention, said Jenny Roe, a professor in the School of the Built Environment at Heriot-Watt University, who oversaw the study. “Natural environments still engage” the brain, she said, but the attention demanded “is effortless. It’s called involuntary attention in psychology. It holds our attention while at the same time allowing scope for reflection,” and providing a palliative to the nonstop attentional demands of typical, city streets.
Of course, her study was small, more of a pilot study of the nifty new, portable EEG technology than a definitive examination of the cognitive effects of seeing green.
But even so, she said, the findings were consistent and strong and, from the viewpoint of those of us over-engaged in attention-hogging urban lives, valuable. The study suggests that, right about now, you should consider “taking a break from work,” Dr. Roe said, and “going for a walk in a green space or just sitting, or even viewing green spaces from your office window.” This is not unproductive lollygagging, Dr. Roe helpfully assured us. “It is likely to have a restorative effect and help with attention fatigue and stress recovery.”
-by Gretchen Reynolds, The New York Times
Mindfulness from meditation associated with lower stress hormone
Focusing on the present rather than letting the mind drift may help to lower levels of the stress hormone cortisol, suggests new research from the Shamatha Project at the University of California, Davis.
The ability to focus mental resources on immediate experience is an aspect of mindfulness, which can be improved by meditation training.
“This is the first study to show a direct relation between resting cortisol and scores on any type of mindfulness scale,” said Tonya Jacobs, a postdoctoral researcher at the UC Davis Center for Mind and Brain and first author of a paper describing the work, published this week in the journal Health Psychology.
High levels of cortisol, a hormone produced by the adrenal gland, are associated with physical or emotional stress. Prolonged release of the hormone contributes to wide-ranging, adverse effects on a number of physiological systems.
The new findings are the latest to come from the Shamatha Project, a comprehensive long-term, control-group study of the effects of meditation training on mind and body.
Led by Clifford Saron, associate research scientist at the UC Davis Center for Mind and Brain, the Shamatha Project has drawn the attention of both scientists and Buddhist scholars including the Dalai Lama, who has endorsed the project.
In the new study, Jacobs, Saron and their colleagues used a questionnaire to measure aspects of mindfulness among a group of volunteers before and after an intensive, three-month meditation retreat. They also measured cortisol levels in the volunteers’ saliva.
During the retreat, Buddhist scholar and teacher B. Alan Wallace of the Santa Barbara Institute for Consciousness Studies trained participants in such attentional skills as mindfulness of breathing, observing mental events, and observing the nature of consciousness. Participants also practiced cultivating benevolent mental states, including loving kindness, compassion, empathic joy and equanimity.
At an individual level, there was a correlation between a high score for mindfulness and a low score in cortisol both before and after the retreat. Individuals whose mindfulness score increased after the retreat showed a decrease in cortisol.
“The more a person reported directing their cognitive resources to immediate sensory experience and the task at hand, the lower their resting cortisol,” Jacobs said.
The research did not show a direct cause and effect, Jacobs emphasized. Indeed, she noted that the effect could run either way — reduced levels of cortisol could lead to improved mindfulness, rather than the other way around. Scores on the mindfulness questionnaire increased from pre- to post-retreat, while levels of cortisol did not change overall.
According to Jacobs, training the mind to focus on immediate experience may reduce the propensity to ruminate about the past or worry about the future, thought processes that have been linked to cortisol release.
“The idea that we can train our minds in a way that fosters healthy mental habits and that these habits may be reflected in mind-body relations is not new; it’s been around for thousands of years across various cultures and ideologies,” Jacobs said. “However, this idea is just beginning to be integrated into Western medicine as objective evidence accumulates. Hopefully, studies like this one will contribute to that effort.”
Saron noted that in this study, the authors used the term “mindfulness” to refer to behaviors that are reflected in a particular mindfulness scale, which was the measure used in the study.
“The scale measured the participants’ propensity to let go of distressing thoughts and attend to different sensory domains, daily tasks, and the current contents of their minds. However, this scale may only reflect a subset of qualities that comprise the greater quality of mindfulness, as it is conceived across various contemplative traditions,” he said.
Previous studies from the Shamatha Project have shown that the meditation retreat had positive effects on visual perception, sustained attention, socio-emotional well-being, resting brain activity and on the activity of telomerase, an enzyme important for the long-term health of body cells.
The adrenal cortex produces glucocorticoids e.g. cortisol. Increased secretion of glucocorticoids is called Cushing’s syndrome and has a variety of different causes:
- An increase in activity of the adrenal cortex due a tumour
- A pituitary adenoma which causes an increase in the secretion of ACTH (Cushing’s disease)
- Ectopic secretion of ACTH
ACTH is a hormone that is released from the anterior pituitary and it stimulates the secretion of cortisol. Cortisol in return negatively feeds back to ACTH and inhibits its production.
Cushings syndrome has many symptoms such as
- Increased muscle proteolysis and wassting of muscles which gives the patient thin arms and legs
- Increase lipogenesis which leads to fat depositions in the abdomen, neck and face. This gives the patient a “moon shaped” face and central weight gain
- Thinning of the skin which leads to purple marks and easy bruising
- Immunosupression leading to a greater susceptibility to infections
- Osteoporosis causing back pain and the collapsing of ribs
How Protein and Carbs Work Together to Build Muscle
Hormones play a major role in muscle breakdown and their subsequent rebuilding. Different food groups serve to regulate these hormones, and proper timing of fuel intake can help you fine tune your hormone levels for successful muscle rebuilding.
Cortisol and Insulin
Two hormones that play a vital role in muscle production are cortisol and insulin. Cortisol is created during intense exercise. Its major function is to generate fuel by breaking down muscle stores. Insulin works to reduce cortisol response, helping to decrease muscle breakdown.
Insulin also helps muscles rebuild, but without adequate carbohydrate consumption, muscle cells can become insulin resistant. And protein consumed without carbohydrates is less efficient. That’s why you should consume carbohydrates and protein during a workout.
By consuming carbohydrates during exercise, you can increase insulin production and reduce cortisol’s response. With less cortisol produced, you’ll have less muscle breakdown. Protein allows for sustained energy and helps the body recover faster. Liquid meals, such as a protein smoothie with fruit, are beneficial during this important rebuilding stage because they are easily digested.
Between workouts, carbohydrates and protein work together to fully replenish muscle energy stores and build new muscle. To reap the most benefit, consume carbs and protein at each meal and snack.
The protein recommendation for a strength athlete is 0.9 to 1.2 grams per pound of bodyweight. Different types of protein—whey and casein—help build muscle. Whey is fast acting and best consumed during and immediately following a workout. Casein is more slowly digested. It’s great to take before bed to help minimize muscle loss during the overnight fast.
Here are daily recommendations for all food groups, listed as a percentage of total daily calories:
- Protein — 21-24 percent
- Carbohydrates — 43-46 percent
- Fat — 33 percent
If you follow a 2,000-calorie diet, your daily recommendations would be 105-120 grams of protein/day, 215-230 grams of carbohydrate/day and 73 grams of fat/day.
You can easily meet these dietary requirements without supplements. For example, here is a sample day’s worth of protein:
- Breakfast: 2 eggs = 12 grams protein
- Snack: 2 oz. almonds = 12 grams protein
- Lunch: 6 oz. turkey = 30 grams protein
- Snack: 8 oz. Greek yogurt = 16 grams protein
- Dinner: 6 oz. salmon = 38 grams protein
This adds up to 108 grams of protein. With a little meal planning, you can easily meet your daily requirements.
Sources: Nutrient Timing for Peak Performance, by John Ivy and Robert Portman; Sports Nutrition Guide Book, by Nancy Clark
Cortisol and Alcohol
While doing some research this morning for my upcoming speech on stress, I found an article on About.com that discusses a study correlating cortisol (the ‘stress’ hormone) and alcohol. According to the study by Bryon Adinof, cortisol levels were shown to have increased during several months of heavy drinking, and increased even further after the subjects stopped drinking completely.
“In this study, we show that even persons drinking for several months continue to show elevated levels of cortisol. In addition, levels of cortisol increase even further when the drinking stops. This increase occurs even before alcohol is gone from the body. The daily, heavy drinker may therefore have levels of cortisol two to three times the normal amount throughout the day and night.”
What does cortisol do, anyway?
In my recent post about stress, I outlined some of the effects. At first, cortisol is actually beneficial, it suppresses the immune system, decreasing inflammation response (think allergies and such), increasing cognitive function via aiding in fat, protein and carbohydrate metabolism, and it activates other anti-stress related systems within the body. But, when cortisol is chronically present in higher levels than normal, it has just the opposite effect: increasing inflammation response, decreasing memory capacity, decreasing digestion, increasing blood pressure, and even increasing the chances of cancer and heart disease.
Cortisol can eventually effect sleep, cause mood disruption, cognitive deficits, and diabetes. All of the above effects have also been related to alcohol itself, and it may be that there is an interdependent relationship between this stress hormone and alcohol, working in concert to cause these effects.
“Alcohol can increase cortisol through a variety of mechanisms,” said Adinoff. “Alcohol directly affects many brain chemicals that signal the adrenal glands to produce and secrete cortisol. High levels of intoxication may be interpreted as general ‘stress,’ which could stimulate cortisol release. Finally, after drinking a lot of alcohol for a long time, the sudden stopping of drinking can produce a stressful ‘withdrawal’ state, which can also increase cortisol production.”
So, Is it really worth it?
Don't stress about it, mon
This is just a powerpoint slide I plucked from a previous lecture - credit for the pic goes to Dr M.C.Pardon of the Uni. of Nottingham Medical School (QMC), who does research on stress & neurodegenerative disease.
Adaptive responses to stress are generally more short term and they are usually quite good for you. As a result, one can conclude that some stress is actually good for you. However, too much stress leads to pathological responses which are bad.
Stress responses of the body are mediated by the hypothalamus. The hypothalamus releases a hormone called CRH (corticotropin releasing hormone) into the median eminence, which transports the hormone via the blood to the anterior pituitary. Cells of the anterior pituitary then release ACTH (adrenocorticotrophin releasing hormone) into the blood supply which circulates to the Adrenal glands (which sit on your kidneys like little hats). The adrenals are responsible for releasing all kinds of steroid hormones, but in this context, it’s cortisol they’re releasing. If you want to be all savvy and smart about it, then you cansay that the stress hormone, cortisol, is released by the Zona Fasiculata of the Adrenal Cortex in response to ACTH. Cortisol is a derivative of cholesterol. All steroid hormones are derivatives of cholesterol, for that matter. Examples of steroid hormones are Oestrogens, Testosterone, Progesterone and Aldosterone. As we can see from that non-exhaustive list, cholesterol has a pretty important role to play in your sexuality, sex life, and reproduction.
Examples of Steroid hormones.
Cortisol is the hormone which causes the majority of the bodily changes associated with stress. Most of the effects described in that first picture are the results of cortisol. Stress, through the action of cortisol, leads to the breakdown of energy reserves. This is why prolonged stress leads to weight loss. Evolutionarily, this would have been advantageous as a typical stress response would have been something along the lines of a sabre-toothed cat or lion raiding the camp, and mobilising energy stores would have got you all alert and ready to take on the threat. To continue along this vein, stress downregulates the action of the amygdala (the fear centre), which gives a reason why you might be a little more fearless under stressful situations (such as lion attack). Stress also downregulates the Supraoptic Nucleus of the hypothalamus. This region of the hypothalamus is responsible for releasing Oxytocin. Oxytocin is an important neurohormone involved in social bonding and love. The decreased oxytocin release indicates as to why stressed out people tend to be less sensitive about other people, and more prone to lashing out.
We must remember that stress doesn’t only arise from life threatening situations such as a lion attack or a Justin Bieber concert. Stress responses arise from many daily activities, and the body is aware of this. When you are sleeping, you are under less stress (or unaware of any stressful situations), so your cortisol levels are very low. But prior to waking (which is determined by your body clock and sleeping routine), your cortisol levels rise by a large amount (around 50%, if you’re interested). This is known as a rheostatic mechanism. The body is changing in anticipation of an event. The body is anticipating the stress of daily life, so is releasing cortisol in advance. The body can then adjust to the daily stresses as they come.
So we can see from the initial diagram that too much stress can lead to heart disease, impotence and possibly diabetes (through the insulin resistance). Cortisol also downregulates the immune system, by decreasing the mobility of white blood cells and stimulating less antibody release. It kind of explains why more people get ill at around exam time. Another reason for excessive illness around exam time is that students are getting less sleep (from all that hard studying, of course!), and sleep is important for giving the immune system a kick. Sleep states release melatonin (the sleep hormone), and melatonin upregulates the immune system.
Melatonin and the immune response. Diagram from ‘Melatonin - a pleiotropic molecule involved in pathophysiological processes following organ transplantation’, J. E. Fildes et al, Immunology.
And to cap off this post, some research done by a Professor of Neurology at the University of Minnesota, called Adnan Qureshi (he totally robbed my surname), indicates the cat owners are less likely to suffer from heart attacks. The reason for this is unclear but a couple of theories are that cat owners have personality traits which may protect them from heart attacks, or it may well be the soothing, stress relieving feeling of stroking and looking after the cat that reduces cortisol levels. I’m not sure, and neither is Prof. Qureshi (that name stealing fiend) - but as a cat lover, this news pleases me.
Oxytocin Improves Empathy in the Less Socially Competent
Oxytocin may help treat disorders of social impairment, like autism. A recent study reports interesting results.
Oxytocin may help treat disorders of social impairment, like autism. A recent study reports interesting results.
Oxytocin is a naturally occurring hormone that helps to reduce stress by counter regulating cortisol. Some studies suggest oxytocin makes people more social, leading to speculation that it could treat autism or social anxiety. However, research on oxytocin is still in the early stages.
In recent study, researchers at the Mount Sinai School of Medicine and Columbia University administered synthetic oxytocin to healthy adults. Adults scoring lower on tests of social competency before the experiment scored higher on an empathetic accuracy task if they were administered oxytocin instead of a placebo. Adults scoring higher on tests of social accuracy showed no significant difference.
Further research is needed to determine why oxytocin improves empathy only in adults with lower social competency. Or whether autistic populations would show similar results. However, these initial findings hold much promise.
Synopsis written by Daina Crafa
How the fibromyalgia symptoms can be influenced by hormones
Adrenal Fatigue is one of the most missed conditions in medicine today.
Poor sleep, aches, pains, fatigue, unexplained weight gain, anxiety, depression as well as memory loss….all of these sound familiar?
Each problem to the mind and body creates a demand on the adrenal glands (your body’s stress glands). Today, these problems are endless; the threat of losing your job, a demanding boss, financial pressures, lack of sleep, relationship problems, yo-yo dieting death or illness of a loved one skipping meals, dependence on stimulants such as caffeine and sugar, over-exercise, infection or illness and digestive issues. With this, the result is…. Adrenals are over producing and are constantly on high alert. Thus the over worked adrenal glands are eventually worn out consequential in this commonly missed condition….ADRENAL FATIGUE
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