Moderate drinking does not protect from dementia

22nd August 2010 Health

Drinking lots of alcohol is associated with an increased risk for dementia, but a study published in the American Journal of Epidemiology, (Is There an Association Between Low-to-Moderate Alcohol Consumption and Risk of Cognitive Decline?, doi:10.1093/aje/kwq187), questions the previous assumption that moderate alcohol consumption may protect people from cognitive decline.

Scientists observed 3,900 men and women over the age of 55 who, at the start of the study, had no signs of dementia and were examined again after 2.5 and 4.5 years of follow up. The results show that people who drank very little alcohol (12-24g/day, equivalent of one or two glasses of wine) did not have lower risk for dementia as compared to people who didn’t drink at all. The mixed results from former studies may have been due to inclusion of former drinkers in the abstainers reference category.

Heavy weights not necessary for building muscle

13th August 2010 Health

A new study published in PLoS One, (Low-Load High Volume Resistance Exercise Stimulates Muscle Protein Synthesis More Than High-Load Low Volume Resistance Exercise in Young Men, PLoS ONE 5(8): e12033. doi:10.1371/journal.pone.0012033) questions the dogma that to build muscle size you need to lift heavy weights.

The scientists say that growing muscle means stimulating the muscle to make new proteins, a process that over time accumulates into bigger muscles, and that the critical point is not the weight used but achieving muscle fatigue. The study compared heavy weight, 90% of person’s maximum lift, to light weight, 30% of maximum, which were lifted until exhaustion and used muscle biopsies to observe protein synthesis at rest, 4 and 24 hours after exercise.

Results suggest that low-load high volume resistance training is more effective in inducing acute muscle anabolism than high-load low volume exercise mode. One thing to keep in mind though is that size does not necessarily correlate with strength when it comes to muscles.

Compression only CPR recommended for non-professionals

5th August 2010 Health

Two new studies, Compression-Only CPR or Standard CPR in Out-of-Hospital Cardiac Arrest (N Engl J Med 2010; 363:434-442 July 29, 2010) and CPR with Chest Compression Alone or with Rescue Breathing (N Engl J Med 2010; 363:423-433 July 29, 2010) published in the New England Journal of Medicine conclude that for the untrained person giving CPR with just compression, and not ventilation as traditionally instructed, is effective enough so that it could and should be recommended.

Full CPR with both compression and ventilation is better, but it requires skill in order to get the breathing part right, and a patient suffering from spontaneous cardiac arrest will have enough oxygen in their body for about five minutes, so if help will arrive during that time there is no significant difference in the overall survival rate between standard CPR and compression-only CPR. This means that one should not hesitate to help even if you are unsure of the correct technique of mouth-to-mouth, especially considering that immediately started cardiopulmonary resuscitation dramatically increases the chances of survival for cardiac arrest patients.

Drowning does not look like drowning

3rd August 2010 Health

Mario Vittone, an ex US Navy and Coast Guard member and now a writer on maritime safety, writes that in real life drowning is not the violent, splashing, call for help that most people expect. Dr. Francesco Pia, a water safety expert, lists five important points about the Instinctive Drowning Response, what people do to avoid actual or percieved suffocation in the water, that anyone who deals with safety on or near water should know about:

1. Except in rare circumstances, drowning people are physiologically unable to call out for help. The respiratory system was designed for breathing. Speech is the secondary or overlaid function. Breathing must be fulfilled, before speech occurs.

2. Drowning people’s mouths alternately sink below and reappear above the surface of the water. The mouths of drowning people are not above the surface of the water long enough for them to exhale, inhale, and call out for help. When the drowning people’s mouths are above the surface, they exhale and inhale quickly as their mouths start to sink below the surface of the water.

3. Drowning people cannot wave for help. Nature instinctively forces them to extend their arms laterally and press down on the water’s surface. Pressing down on the surface of the water, permits drowning people to leverage their bodies so they can lift their mouths out of the water to breathe.

4. Throughout the Instinctive Drowning Response, drowning people cannot voluntarily control their arm movements. Physiologically, drowning people who are struggling on the surface of the water cannot stop drowning and perform voluntary movements such as waving for help, moving toward a rescuer, or reaching out for a piece of rescue equipment.

5. From beginning to end of the Instinctive Drowning Response people’s bodies remain upright in the water, with no evidence of a supporting kick. Unless rescued by a trained lifeguard, these drowning people can only struggle on the surface of the water from 20 to 60 seconds before submersion occurs.

This doesn’t mean that people yelling and trashing in the water do not need help, they may be experiencing aquatic distress. But it’s the quiet ones that you should look out for. The principle is the same as in any emergency situation, the people who cry loudest are usually not in the most dire need of help. Sometimes the most common indication that someone is drowning is that they don’t look like they are drowning. So if you see someone silently treading water and are not sure, ask them if they are ok. If they give an answer, they probably are, but if they return a blank stare you may have less than half a minute to get to them.

Astrocytes’ role in breathing

19th July 2010 Science

Astrocytes, the star shaped brain cells previously thought to act only as support and nutrition providers for neurons, have an important role in regulating breathing, say scientists from UCL and University of Bristol. (Astrocytes Control Breathing Through pH-Dependent Release of ATP, Science, 2010; doi: 10.1126/science.1190721)

The research demonstrates that astrocytes are able to sense the level of carbon dioxide in the arterial blood entering the brain and then activate the neuronal respiratory network in the brain to increase breathing in accord with prevailing metabolism and activity. This finding places astrocytes at the center of a fundamental regulatory reflex which subconsciously continually adjusts our breathing.

Daily ginger reduces post exercise muscle pain

30th April 2010 Health

A report published in the Journal of Pain, (Ginger (Zingiber officinale) Reduces Muscle Pain Caused by Eccentric Exercise, doi:10.1016/j.jpain.2009.12.013), reports that a dose of 2 grams of ginger daily effectively reduces muscle pain caused by eccentric exercise.

Two double-blinded random controlled trials compared the effects of either raw or heat-treated ginger to placebo. Participants consumed 2 grams of ginger or placebo for 11 consecutive days. They then performed 18 eccentric actions on the elbow flexors to induce pain and inflammation. Pain intensity, perceived effort, range-of-motion and isometric strength among other things were assessed prior to and for 3 days after exercise.

Results showed that both raw and heat-treated ginger resulted in similar pain reductions 24 hours after exercise compared to placebo. Smaller effects were noted between ginger and placebo on other measures. There was no difference between raw or heat-treated ginger, but the study concludes that daily consumption of either is effective in reducing muscled pain following exercise-induced muscle injury.

Shoes and osteoarthritis

25th March 2010 Health

At least two studies have recently reported that the kind of footwear one uses can have significant effect on the load placed on joints while walking or running.
First a study published in PM&R (The Effect of Running Shoes on Lower Extremity Joint Torques, doi:10.1016/j.pmrj.2009.09.011) compared the effects of running barefoot versus running in modern running shoes and observed increased joint torques in knee, hip and ankle joints with running shoes. The findings confirm that while modern running shoes provide good support for the foot itself they increase the stress exerted on lower extremity joints. The researchers suggest that this is largely caused by an elevated heel and increased material under the medial arch.

Another study published in Arthritis Care & Research reports that flat, flexible footwear significantly reduces the load on the knee joints compared to supportive, stable shoes with less flexible soles. This finding is important, because loading on the knee joint is a key factor in the development of osteoarthritis. This study also lists heel height and material stiffness as factors behind increased joint load.

More evidence for Naprapathy

23rd March 2010 Health

A study published in BMC Musculoskeletal Disorders (The long-term effects of naprapathic manual therapy on back and neck pain - Results from a pragmatic randomized controlled trial; BMC Musculoskeletal Disorders 2010, 11:26 doi:10.1186/1471-2474-11-26) compares long-term - up to one year - effectiveness of naprapathy and evidence-based advice on staying active regarding non-specific back and/or neck pain.

A group of 409 people, who had non-specific back and/or neck pain lasting at least two weeks, were included and the interventions compared were naprapathic manual therapy, such as spinal manipulation/mobilization, stretching and massage, (index group) and advice to stay active and how to cope with pain provided by a physician (control group). 89% of the participants completed 26-week follow up and 85% 52-week follow up.

The results were that a higher proportion in the index group had clinically important decrease in pain and disability both in 26-week and 52-week follow ups and the differences between the groups considered over one year were statistically significant favoring naprapathy.

Replacing saturated fat with unsaturated fat healthy

22nd March 2010 Health

The connection of fat in diet to cardiovascular diseases has been unclear, but a new study published in PLoS Medicine (Effects on Coronary Heart Disease of Increasing Polyunsaturated Fat in Place of Saturated Fat: A Systematic Review and Meta-Analysis of Randomized Controlled Trials) reports that replacing saturated fat with polyunsaturated fat could decrease the risk of coronary hearth disease up to 19%.

These findings were achieved by systematically reviewing large group of RCT studies and doing a pooled meta-analysis on them. Prior to this study the findings have been mixed, which may be due to absense of focus on the specific replacement of saturated fat (was it replaced with carbohydrates, monounsaturated or with polyunsaturated fat).

High-intensity interval training as effective as endurance exercise

13th March 2010 Health

A study published in The Journal of Physiology, (A practical model of low-volume high-intensity interval training induces mitochondrial biogenesis in human skeletal muscle: potential mechanisms, doi:10.1113/jphysiol.2009.181743), reports that high-intensity interval training (HIT) can yield similar health benefits as moderate long term training.

Moderate long term exercise, such as running or cycling for several hours a week, improves oxygen delivery to muscles, widens the blood vessels to muscle cells and both improves the efficiency as well as boosts the number of mitochondria in them. This study aimed to prove that same effects can be achieved in less time doing HIT exercises, such as 10 one-minute sprints with short recovery time between.

The study recruited seven men, average age 21, and had them perform 6 training sessions over 2 weeks on a regular stationary bike. Each session comprised between 8 and 12 one minute intervals at around 100% of peak power output (as measured from peak VO2) separated by 75 seconds of rest.

Results from the study found significant increase in exercise capacity in two cycling time trials as well as increased maximal activity of mitochondrial capacity in quadriceps biopsies. To achieve the same results by endurance training over the same two week period you would have to do over 10 hours of continuous moderate cycling exercise, says one of the researchers.

Barefoot running easier on feet

1st February 2010 Health

In a study published in Nature, (Foot strike patterns and collision forces in habitually barefoot versus shod runners, Nature 463, 531-535, doi:10.1038/nature08723), Harvard scientists compared barefoot running, or running in minimal footwear, to running in modern running shoes.

Researchers looked at the running gait of three groups of people: those who had always run barefoot, those who had always worn shoes and those who had converted to barefoot running from shod running. Most shod runners heel-strike while people who run barefoot tend to land with a springy step toward the middle or front of the foot. Landing on the ball or middle of the foot enables the runner to use the architecture of the foot and leg to avoid hurtful and potentially damaging impacts, equivalent to two to three times body weight, that shod heel-strikers repeatedly experience.

The authors conclude that "Humans have engaged in endurance running for millions of years, but the modern running shoe was not invented until the 1970s. For most of human evolutionary history, runners were either barefoot or wore minimal footwear such as sandals or moccasins with smaller heels and little cushioning." and "Running barefoot or in minimal shoes is fun but uses different muscles. If you’ve been a heel-striker all your life, you have to transition slowly to build strength in your calf and foot muscles."

More information from Harvard University.

Learning styles debunked

16th December 2009 Science

Despite widely held beliefs that each person has a preferred learning style which affects the effectiveness of learning, there is no scientific evidence to back up the idea that some students would learn better when material is presented visually and others with verbal presentation. A report published in Psychological Science in the Public Interest reviewed existing literature on learning styles and concluded that no credible studies support this theory of different kind of learners.

Problems with moral dilemma scenarios

15th December 2009 Science

Psychology and other studies often use hypothetical scenarios, such as deciding what to do in a situation with only bad outcomes, like a trolley heading towards helpless victims that can be only stopped by pushing someone else in front of it, to study moral judgement.

However, a study published in Cognitive Science (Moral Principles or Consumer Preferences? Alternative Framings of the Trolley Problem, Cognitive Science, 34: 311–321. doi: 10.1111/j.1551-6709.2009.01088.x) reports problems with drawing conclusions from this kind of studies. The researchers found that small changes in the wording of such questions can affect the judgements in ways that have nothing to do with differences in moral principles. They also found that it is difficult to distinguish between the influence of moral principles and more general biases.

Hidden sensory system in the skin

8th December 2009 Science

A groundbreaking study published in the journal Pain (Absence of pain with hyperhidrosis: A new syndrome where vascular afferents may mediate cutaneous sensation. PAIN. 2009 Dec 15;147(1-3):287-98.) reports that human body has an entirely unique and separate sensory system apart from the nerves that give most of us the ability to touch and feel.

This sensory network, which for most people is largely imperceptible, is located throughout our blood vessels and sweat glands and may help explain why persons lacking known nerve receptors can still have the sense of touch and may also help explain the causes of unexplained pain like fibromyalgia. The research team came across this finding when they were studying two patients with extremely rare condition known as congenital insensitivity to pain. Tests revealed that while the patients had a severe lack of pain sensation and all skin sensations were severely impaired, including the response to different temperatures and mechanical contact, they still had adequate sensations for daily living and could differentiate between hot and cold, rough and smooth etc. Microscopic analysis of skin samples from the patients showed that their skin lacked all the normal nerve endings associated with skin sensation.

The answer appears to be in the nerve endings found in blood vessels and sweat glands, which were previously thought to be associated with regulating blood flow and sweating. Somehow the two individuals in question were able to "feel things" through these remaining nerve endings.

Physiological function of dreams

13th November 2009 Science

A study published in Nature Reviews Neuroscience (REM sleep and dreaming: towards a theory of protoconsciousness; doi:10.1038/nrn2716) suggests that besides their percieved psychological function, dreams may actually have a crucial physiological role as well. According to the researchers the major function of REM sleep is "warming up" the brain, activating and anticipating the sensory inputs it receives when in a waking state. A kind of physiological brain exercise, like jogging, that tunes the brain for conscious awareness.

More pain equals more gain in CRPS

13th November 2009 Health

Complex Regional Pain Syndrome (CRPS) is chronic progressive disease characterized by severe pain, swelling and changes in the skin. While it may follow injury or surgery, that is not always the case, and the real cause for the syndrome is currently unknown. Type I CRPS which, unlike Type II, does not involve nerve lesions, was the subject of a study done in Department of Rehabilitation Medicine at Bethesda Hospital. The results were published in Clinical Rehabilitation, (Pain exposure physical therapy may be a safe and effective treatment for longstanding complex regional pain syndrome type 1: a case series, doi: 10.1177/0269215509339875).

The study observed 106 patients who were treated with pain exposure physical therapy, which is aimed at functional improvement of the affected limb while neglecting pain. Normal use of the limb between treatments was encouraged despite pain. Traditional treatments for Type I CRPS typically minimize the pain, which limits physiotherapy significantly and usually leads to greater deterioriation of the affected limb.

In 95 patients (45%) the function of the affected arm or leg improved and 49 of them (46%) experienced full functional recovery. 75 patients presented reduction in pain and in 23 patients functional recovery was reached despite increased pain. Four patients stopped early due to pain increase. These results suggest that pain exposure physical therapy is effective and safe for patients who are unresponsive to accepted standard therapies. Avoiding the use of a limb due to pain will result in loss of function while forced usage of limbs restores the function, reverses these adaptive processes and leads to regain of control by practice with a reduction of pain in most cases.

The authors note that one of the cornerstones of the success of pain exposure physical therapy is to motivate the patient to undergo both the painful interventions and to keep training and exercising at home.

Moderate amount of protein best for muscle building

30th October 2009 Health

Protein is necessary for building muscles, but just how much protein is necessary per meal has been a question for long time. Now a study by University of Texas Medical Branch, published in the Journal of American Dietetic Association, aims to answer this question.

The researchers measured muscle protein synthesis rates using blood samples and thigh biopsies from 34 volunteers - half of them young, half elderly - after eating meals that contained different amounts of protein. They found that 30 grams of protein per meal - equivalent of about 113g of meat, dairy or soy - increased the rate of muscle protein synthesis by 50 percent and higher amounts of protein per meal did not give further increase. So it seems that protein synthesis hits a cap at 30g per meal and the researchers recommend trying to balance the protein intake throughout the day instead of consuming large amounts in one meal.

Placebo comes from the spine

20th October 2009 Science

A study published in Science, (Direct Evidence for Spinal Cord Involvement in Placebo Analgesia, Science 16 October 2009: Vol. 326. no. 5951, p. 404 doi: 10.1126/science.1180142), was able to find quantitative-observable physical evidence of the effects of suggestion.

The study used a series of systematic and highly suggestive tools to trick volunteers into believing they had been administered a potent analgesic. Participants’ forearms were treated with either, what they thought was, anesthetic cream or placebo. Painful heat was then applied to the area and while both creams were in fact inactive, the fMRI scans showed significantly reduced nerve activity in the dorsal horn region of the spinal cord when the participant thought they had received analgesic cream.

How the brain learns to see

11th October 2009 Science

A study by MIT neuroscientists looked into how the brain learns to identify visual shapes and signals by observing patients who had recently had their sight restored. The patients were shown different pictures and asked to identify and trace the shapes they saw.

One such patient who suffered form a rare form of congenital lack of lenses in the eye was treated with corrective optics at the age of 29. When shown a collection of simple shapes, such as squares and rectangles, he was able to identify the shapes when they were side by side but not when they overlapped. His brain was unable to distinguish the outlines of the whole shape and instead believed each fragment of a shape to be its own whole. Putting the shape into motion increased the success rate from near zero to almost 75 percent. During the next 18 months after the treatment the patient’s performance with stationary objects gradually improved to almost normal.

The results suggest that movement patterns provide the brain with some of the most important clues about surroundings and that the brain is "programmed" to use similarity of dynamics to infer which regions constitute objects.

Evolutionary benefits of cooked food

10th October 2009 Science

In his book Catching Fire: How Cooking Made Us Human primatologist Richard Wrangham discusses his theory about how cooking gave early humans an advantage over other primates, and why homo sapiens cannot survive on raw food only. While cooking food is a uniquely human phenomenon, tests done on the great apes uniformly show preference for cooked food over raw or at least no preference between items, they never prefer raw to cooked, so it is likely that our ancestors were the same.

Eating cooked food has also given the homo sapiens a digestive system that is very different from that of the great apes, it’s less than two thirds of the size it would be if we were like chimpanzee or gorilla. What this means is that while other apes can thrive on a raw food diet, the humans can not. This all points to the fact that we are adapted to a very high quality diet and cooking is probably responsible for this.

One obvious benefit from cooking is that it makes nutrients more absorbable. With raw food there is a significant probability that a particular nutrient will pass through the gut undigested. For example about 94% of the protein in cooked eggs is digested as compared to only 55 to 64 percent from raw eggs. The reason behind this is that heating protein makes it lose its structure - denaturation - which makes it much easier for digestive enzymes to process it. And the same thing happens with starch.

So even if the calorie count of cooked and raw foods are the same, eating the cooked ingredients will produce higher net calorie gain.

Too much antioxidants not so good either

9th October 2009 Health

It is a well known fact that reactive oxygen species (ROS) - also known as free radicals - can damage our cells and that antioxidant vitamins can help in reducing that damage, but a new report from Monash University - published in Cell Metabolism - suggests that things are not so simple in nature.

The researchers found that low levels ROS - especially hydrogen peroxide - may actually protect us from diabetes by improving our ability to respond to insuling signals. The study’s leader says that whether antioxidants are ultimately good or bad for people depends on their state of health or disease and that according to their research antioxidants might actually be bad for someone in an early stage of type 2 diabetes and developing insulin resistance. He also suggests that rather than take daily antioxidant vitamin supplements, healthy people should exercise instead as that is a natural source of insulin action promoting ROS.

Vitamin B not effective in preventing cardiovascular diseases

8th October 2009 Health

A Cochranew Review (Homocysteine lowering interventions for preventing cardiovascular events, doi: 10.1002/14651858.CD006612.pub2) looked into eight RCT studies - observing total of 24,210 people - to find out if B vitamin supplementation might reduce the risk of myocardial infarction, stroke or angina pectoris. The review found no evidence to support the theory that supplements of vitamins B6, B9 or B12 alone or in combinations, at any dosage, prevents cardiovascular events or reduces total mortality in participants at risk or with established cardiovascular disease.

Magnet bracelets ineffective

7th October 2009 Health

A University of New York study investigated the effectiveness of widely used alternative therapies, copper bracelets and magnetic wrist straps, for managing and relieving arthritis pain. The researchers had 45 people, who all were diagnosed with osteoarthritis, wear four devices in random order over a 16-week period: two wrist straps with different levels of magnetism, one copper bracelet and a demagnetized wrist strap.

The results found no meaningful difference between the devices in term of their effect on pain, stiffness or physical function and the study’s lead scientist concludes that any percieved benefit obtained from such devices is most likely due to psychological placebo effect or temporal connection - people tend to buy these device when they experience the most pain, and when the pain lessens over time due to natural causes they attribute it to the device.

Enhanced interrogation is counterproductive

7th October 2009 Science

A study published in Trends in Cognitive Sciences (Torturing the brain: On the folk psychology and folk neurobiology motivating ‘enhanced and coercive interrogation techniques’) suggests that the belief in the effectiveness of torture is a myth not supported by scientific evidence and does not fit with the current knowledge about how the brain works.

The brain regions most concerned with memory recall, the prefrontal cortext and hippocampus, can be damaged by stress hormones such as cortisol and catecholamines that are produced during "enhanced interrogation" like prolonged sleep deprivation, confinement in stressful or painful conditions or torture. Continued stress can even lead to tissue loss in these brain areas, which makes recalling accurate information even less likely and increases the likelyhood of false memories replacing real ones. Eventually a person subjected to continuous stress will became unable to distinguish between real and false memories at all.

Gun possession more likely to get you shot

6th October 2009 Science

In a pioneering study epidemiologists at University of Pennsylvania School of Medicine investigated the link between being shot in an assault and a person’s possession of a gun at the time of the shooting. The estimate was that people with a gun were four and a half times more likely to be shot than those not possessing a gun during an assault.

Believing is seeing

5th October 2009 Science

A study done by international team of psychologists found that our preconceptions influence the way we percieve what we see, at least when it comes to interpreting other people’s emotions from facial clues. In the research participants were showed still photographs of faces that were morphed to express ambiguous emotion and were instructed to think of these faces as either happy or angry. They then watched an animation of the face changing form angry to happy and were asked to pick the picture they had first seen.

The result was that participants memories were affected by their initial interpretation, so that faces interpreted as angry were remembered as expressing more anger than faces initially interpreted as happy. What was even more interesting, the researchers found that when viewing the ambiguous faces again the participants imitated their previously interpreted emotion, so that when viewing a face they thought was angry the participants expressed more anger themselves.

What this all means is that in real social interactions, where facial expressions are often a blend of multiple emotions, two people can have different recollections about the same emotional even and still be both "right".

Teachers’ misconceptions about the brain

3rd October 2009 Science

A University of Bristol study that questioned trainee teachers found out that many of them accepted popular myths about the brain that have been discounted by neuroscientists. Some common misconceptions included that brains could shrink if one did not drink enough water or that attention was not needed for learning. 82% of trainees also thought that "individuals learn better when they receive information information in their preferred learning style" even though there is no supporting evidence that identifying learning styles has educational value.

Tetris for brain improvement

2nd October 2009 Science

Playing tetris for 30 minutes a day over three months was the task assigned to 26 adolescent girls in an effort to study if practice makes the brain efficient because it increases the amount of gray matter.

In the study published in the open access journal BMC Research Notes, MRI assessment of cortical thickness and functional activity changes in adolescent girls following three months of practice on a visual-spatial task (BMC Research Notes 2009, 2:174; doi:10.1186/1756-0500-2-174), the team of researchers at Mind Research Network found that while the tetris player had greater brain efficiency and thicker cortex than control group, the cortex thickening was not associated with the brain areas that showed more efficiency.

They conclude that while difference in cortical thickness was an exciting finding, the relationship between thicker cortex and brain efficiency remains a mystery and focus for further studies.

How much omega-3 is enough to prevent cardiovascular disease?

10th September 2009 Health

Just about 200 milligrams per day, says research published in FASEB Journal (Increasing intakes of the long-chain {omega}-3 docosahexaenoic acid: effects on platelet functions and redox status in healthy men; The FASEB Journal. 2009;23:2909-2916).

The team of French scientist examined the effects of different doses of DHA in a group of 12 healthy men between age 53 and 65. The subjects consumed doses of DHA from 200 to 1600 mg per day and researchers examined blood and urine samples for biochemical markers that are used to predict cardiovascular problems. The result was that these markers are reliably affected already with a 200 mg dose.

Mechanism for placebo analgesia

1st September 2009 Science

A study published in Neuron, Activation of the Opioidergic Descending Pain Control System Underlies Placebo Analgesia (volume 63 issue 4 pp.533 - 543), looks into the mechanisms involved in placebo analgesia. Researchers combined naloxene - an opioid antagonist - administration with functional magnetic resonance imaging and found out that naloxene reduced both behavioral and neural placebo effects. These findings mean that the endogenous opioid system plays a role in placebo analgesia.

Low carb diet and atherosclerosis

26th August 2009 Health

A study done in Beth Israel Deaconess Medical Center found that mice placed on a 12-week low carbohydrate / high protein diet had increased atherosclerosis and impaired ability to form new blood vessels.

The researches studied three groups of mice: one fed a standard mouse diet (65% carbs, 15% fat, 20% protein), one a regular "western" diet (43% carbs, 42% fat, 15% protein) and one getting a low-carb / high protein diet (12% carbs, 43% fat, 45% protein). Observations were made after 6 and after 12 weeks and consistently with what has been observed with humans, the mice on low-carb diet gained 28% less weight compared to the ones eating a Western fare. However, closer study revealed that the low-carb group had significantly larger (15.3% vs 8.8%) accumulation of plaque in blood vessels, a standard measure for atherosceloris.

In further research the authors found that the amount of EPC cells, which may play a role in vascular health, dropped 40% in two weeks in the low-carb mice. Although the role of EPC cells is not fully understood and extrapolating findings from animal studies to humans should be done cautiously, the results were striking enough that one scientist in the research group changed their low-carb diet back to normal.

The problem with impact factors

15th August 2009 Science

Matt Wedel, a paleontologist, writes about what’s wrong with the impact factor centered culture in his blog post Reason #317 to be depressed: journal impact factors.

One issue is of course that journal impact factors are used by people to measure how good or hot your research is instead of looking at the actual study itself, which is a problem because many publications and journals are not given an impact factor rating at all not to mention that the number of citings your paper gets does not necessarily reflect how good it actually is (a very bad paper may also get cited a lot, because of how bad it is).

The main thing however is that impact factors are not actually calculated in a transparent way by an impartial entity but are actually produced by Thomson Scientific, a for-profit organization, in an arbitrary, undisclosed and subjective manner. What this means is that science is being rated by a process that is itself unscientific and subjective. (The Impact Factor Game, PLoS Med 3(6): e291. doi:10.1371/journal.pmed.0030291)

Why voting age should stay high

4th August 2009 Science

In the Guardian article Brain just isn’t ready to vote at 16 Rickhard Dawkins and R Elisabeth Cornwell explain why young people should not be making life altering decisions, yet alone be able to make those for others.

The answer: their brains just are not up to it. Neuroscientists have found out that from the onset of puberty till their early twenties the human brain goes through major reconstruction, specifically the parts that enable us to think in the abstract, weight moral dilemmas and control our impulses (namely frontal lobes or prefrontal cortex).

While the speed of individual development varies on average and as a whole the teenage brain is still "under construction" and as such we should not expect or require them to be able to act like adults.

Naprapathy works

3rd August 2009 Health

A study published in The Clinical Journal of Pain (Naprapathic Manual Therapy or Evidence-based Care for Back and Neck Pain: A Randomized, Controlled Trial, 2007 Jun;23(5):431-9, doi: 10.1097/AJP.0b013e31805593d8) by Eva Skillgate, Eva Vingård and Lars Alfredsson compared naprapathic manual therapy with interventions used by doctors for back or neck pain. Karolinska Instituted, one of the largest medical universities in Europe, called it a Scientific breakthrough for naprapathy in their own article.

In the study 409 patients were randomly assigned to recieve treatment either from a naprapath or a physician. Twelve weeks after the start, over half of the patients who had been treated by naprapath reported significant improvement, compared to 13% in the other group.

While one study is not conclusive proof about the effectiveness of any form of therapy, this clearly indicates need for more studies with longer follow ups and definitely suggests going to a naprapath as a viable option if you are having neck or back pain.

We don’t know quite as much as we would like

3rd August 2009 Science

As Clinical Evidence survey points out the actual evidence based scientific knowledge about the effectiveness or effects of medical treatments is not as good as one might think. Of course the most widely used methods are well researched and documented and even the rest is usually backed up by knowledge gained from years and years of clinical experience, but the fact remains that of the great variety of different options for treatment, only 13% we know for sure to be beneficial and of 46% there is no conclusive evidence either way.

Apes that write, start fires and play Pac-Man

1st August 2009 Science

In 2009 TED conference Susan Savage-Rumbaugh, who has done a lifetime of studies with our hairy cousins, talks about the apes and their skills. It seems that the more we learn about other forms of life on this planet Eath, the less unique this homo sapiens creature that has crowned itself the King of Creation appears.

Escher for real

1st August 2009 Entertainment

Everyone knows (or if you don’t, find out) the impossible constructions of M.C. Escher, but it’s not always obvious that many of the objects can be constructed as real models that appear similar when viewed from certain angle, like demonstrated by Gershon Elber from Technion Computer Science Department.

Text only Star Wars

1st August 2009 Entertainment

Some people really have too much time and too little to do. Simon Jansen made the whole Episode IV into an ascii animation and put the thing online as java applet. Then along came Sten Spans and put the thing online via telnet. Pure fan genius!

Benefits of meditation

31st July 2009 Science

In recent years scientific research has been able to gather evidence for what people have known for thousands of years; meditation is good for you.

Zen Meditation Really Does Clear the Mind researcher Giuseppe Pagnoni, a neuroscientist at Emory University in Atlanta, and his colleagues find. Their study, (Pagnoni G, Cekic M, Guo Y (2008) “Thinking about Not-Thinking”: Neural Correlates of Conceptual Processing during Zen Meditation. PLoS ONE 3(9): e3083. doi:10.1371/journal.pone.0003083) compared 12 people who had done more than three years of daily Zen meditation practice with 12 novices who had never practiced meditation.

The volunteers were told to concentrate on their breathing and while having their brains scanned using fMRI were every now and then asked to identify a real word from a nonsensical word displayed at a computer screen. The scans revealed that Zen practice led to different activity in a set of brain regions known as the "default network", which is linked with spontaneous bursts of thought and wandering minds. After volunteers experienced in Zen were distracted by the computer, their brains returned faster to how they were before the interruption than novice brains did. This effect was especially striking in the angular gyrus, a brain region important for processing language. New Scientist also has a blog post about the study.

Proceedings of the National Academy of Sciences also has a few interesting studies with full text freely available:

Long-term meditators self-induce high-amplitude gamma synchrony during mental practice by Antoine Lutz, Lawrence L. Greischar, Nancy B. Rawlings, Matthieu Ricard and Richard J. Davidson (PNAS November 16, 2004 vol. 101 no. 46 16369-16373) finds that long-term Buddhist practitioners self-induce sustained electroencephalographic high-amplitude gamma-band oscillations and phase-synchrony during meditation.

Short-term meditation training improves attention and self-regulation by Yi-Yuan Tang, Yinghua Ma, Junhong Wang, Yaxin Fan, Shigang Feng, Qilin Lu, Qingbao Yu, Danni Sui, Mary K. Rothbart, Ming Fan and Michael I. Posner (PNAS October 23, 2007 vol. 104 no. 43 17152-17156) reports that a group randomly assigned to 5 days of meditation practice with integrative body–mind training method shows significantly better attention and control of stress than a similarly chosen control group given relaxation training.

Brain scans show meditation changes minds, increases attention says study done by Richard Davidson and others at University of Wisconsin. The study compared novice meditators with people who had over 54 thousand hours of meditation practice using MRI scanning to reveal which parts of the brain are active at any given moment and found that meditation increased activity in the parts associated with paying attention and making decisions.

The changes were associated with the practice of concentration meditation where practitioners were instructed to focus attention intently on a stimulus, and when the attention wandered off, to simply bring the attention back to the object. While brain activity increased with all participants the most experienced practitioners, however, showed increase only at the beginning and then activity levels came back to baseline, suggesting they were able to concentrate effortlessly.

In the study participants meditated inside MRI scanner and researched pediorically blasted them with disturbing noises. The more experience a particular subject had in meditating, the less effect the distraction had on their brains, with people having over 40.000 hours of experience showed hardly any effect at all. The study is available as full text article in PNAS website: Neural correlates of attentional expertise in long-term meditation practitioners by J. A. Brefczynski-Lewis, A. Lutz, H. S. Schaefer, D. B. Levinson and R. J. Davidson (PNAS July 3, 2007 vol. 104 no. 27 11483-11488).

In the article Davidson also mentions another study which showed that three months of meditation training improved the ability to notice brief visual signals that most people cannot detect. Scientific American has a video report about it, Meditation Enhances Attention by Christie Nicholson.

New Scientist also has two interesting studies to report.

First, a study done by Bruce O’Hara and others from University of Kentucky found out that meditation has a clear and drastic effect on performance. Ten volunteers were tested before and after 40 minutes of either sleep, meditation, reading or light conversation, with all subjects trying all conditions.

The test consisted of staring at a computer screen and pressing a button as soon as an image appears. Typical response times are around 200 to 300 milliseconds while sleep-deprived people respond much slower and sometimes miss the stimulus alltogether. While the 40 minute nap is known to improve performance in this type of test (after an hour or so to recover from grogginess), the researchers found that meditation was the only intervention that immediately improved performance for all test subjects and the results were even more dramatic after a night without sleep.

Another study, done by Sara Lazar and colleagues at the Massachusetts General Hospital, used fMRI to compare 15 experience meditators with 15 non-meditators. They found that meditating actually increases the thickness of the cortex in areas involved in attention and sensory processing, such as the prefrontal cortex and the right anterior insula. The growth of the cortex is not due to the growth of new neurons, but results from wider blood vessels, more supporting structures such as glia and astrocytes, and increased branching and connections.

Scientific American has an online article about how meditation can cultivate compassion. A study done by Antoine Lutz, Julie Brefczynski-Lewis, Tom Johnstone and Richard J. Davidson (Lutz A, Brefczynski-Lewis J, Johnstone T, Davidson RJ (2008) Regulation of the Neural Circuitry of Emotion by Compassion Meditation: Effects of Meditative Expertise. PLoS ONE 3(3): e1897. doi:10.1371/journal.pone.0001897) found that concentrating on the loving kindness one feels towards one’s family and expanding that to include strangers physically affects brain regions that play a role in empathy.

When participants who were long time meditation practitioners were subjected to emotion inducing sounds, such as a woman screaming or a baby laughing, their brains showed more activity than novice meditators in areas that play a role in understanding other’s emotions (like right temporal-parietal juncture).

Science Daily reports of a study that suggest Buddhist Deity Meditation Temporarily Augments Visuospatial Abilities. Done by Maria Kozhevnikov of George Mason University, and published in Psychological Science (Kozhevnikov et al. The Enhancement of Visuospatial Processing Efficiency Through Buddhist Deity Meditation. Psychological Science, 2009), the study compared mental rotation abilities and visual memory of practitioners of two specific types of meditation to nonmeditating people. Initial findings suggest that while meditation does not increase overall visuospatial abilities, it does allow practitioners to temporarily access greater levels of visuospatial memory resources following the meditation period.

Researchers at UCLA using MRI to scan the brains of people who meditate found out that meditation may increase gray matter. In the study Eileen Luders and colleagues compared 22 people who had practiced some form of meditation with 22 people who had no meditation experience.

The researchers found significantly larger cerebral measurements in meditators compared with controls, including larger volumes of the right hippocampus and increased gray matter in the right orbito-frontal cortex, the right thalamus and the left inferior temporal lobe. It is also noteworthy that there were no regions where controls had significantly larger volumes or more gray matter than meditators.

Researchers at UCLA also suggest that Practice of mindfulness meditation slows the progression of HIV. The proposed method how this works is by reducing stress which has a negative effect on CD4+ T lymphocytes, cells that coordinate the immune system’s activity when it becomes under attack and which the HIV virus attacks. Stress can accelerate the decline of CD4 T cells and the study found that practice of meditation stopped this in HIV patients who were suffering from stress, thus slowing the progression of the disease.

Also interesting is the University of Oregon article about how one form of meditative training produces measurable changes in attention and stress reduction: Chinese data unraveled at University of Oregon show a training technique has brain, physiological linkage.

Scam journals

31st July 2009 Science

As reported all over the web, Merck - a major pharmaceutical company - made a phony peer review journal (Australasian Journal of Bone and Joint Medicine) just to promote their products.

The issue was brought to light by The Scientist blog. Apparently Merck paid Elsevier, a major science publisher, to produce a real looking publication that contained only reprinted or summarized articles that presented data favourable to Merck products. In the aftermath it seems this was not an isolated case either, but Elsevier actually put out 6 fake journals between the years 2000 and 2005.

Checking your sources, even when it comes to allegedly peer reviewed scientific publications, is of course always necessary, but this incident demonstrates clearly why it is so important and sadly also how money sometimes goes before morals in any field and has certainly made me look at other Elsevier publications with a doubtful eye. What can you say? For Shame, Merck and Elsevier.