What Caffeine Actually Does To Your Brain

What Caffeine Actually Does To Your Brain:

by Kevin Purdy

For all of its wild popularity, caffeine is one seriously misunderstood substance. It’s not a simple upper, and it works differently on different people with different tolerances — even in different menstrual cycles. But you can make it work better for you.

Photo by rbrwr.

Editor’s Note: This was first published on Lifehacker Australia, and it’s still incredibly relevant to Sleep Week, especially considering all those vodka and Red Bull’s you’ll be drinking tonight at the club. Perhaps you should read this first?

We’ve covered all kinds of caffeine “hacks”, from taking “caffeine naps” to getting “optimally wired”. But when it comes to why so many of us love our coffee, tea or soft-drink fixes, and what they actually do to our busy brains, we’ve never really dug in.

While there’s a whole lot one can read on caffeine, most of it falls in the realm of highly specific medical research or often conflicting anecdotal evidence. Luckily one intrepid reader and writer has actually done that reading, weighed that evidence and put together a highly readable treatise on the subject. Buzz: The Science and Lore of Alcohol and Caffeine, by Stephen R. Braun, is well worth the short 224-page read. It was released in 1997, but remains the most accessible treatise on what is and isn’t understood about what caffeine and alcohol do to the brain. It’s not a social history of coffee, or a lecture on the evils of mass-market soft drinks — it’s condensed but clean science.

What follows is a brief explainer on how caffeine affects productivity, drawn fromBuzz and other sources noted at bottom. We also sent Braun a few of the questions that arose while reading, and he graciously agreed to answer them.

Caffeine Doesn’t Actually Get You Wired

Right off the bat, it’s worth stating again: the human brain and caffeine are nowhere near totally understood and easily explained by modern science. That said, there is a general consensus on how a compound found all over nature, caffeine, affects the mind.

Every moment that you’re awake, the neurons in your brain are firing away. As those neurons fire, they produce adenosine as a byproduct, but adenosine is far from excrement. Your nervous system is actively monitoring adenosine levels through receptors. Normally when adenosine levels reached a certain point in your brain and spinal cord, your body will start nudging you toward sleep, or at least taking it easy. There are actually a few different adenosine receptors throughout the body, but the one caffeine seems to interact with most directly is the A1 receptor. More on that later.

Enter caffeine. It occurs in all kinds of plants, and chemical relatives of caffeine are found in your own body. But taken in substantial amounts — the semi-standard 100mg that comes from a strong eight-ounce coffee, for instance — it functions as a supremely talented adenosine impersonator. It heads right for the adenosine receptors in your system and, because of its similarities to adenosine, it’s accepted by your body as the real thing and gets into the receptors.

More important than just fitting in, though, caffeine actually binds to those receptors in efficient fashion, but doesn’t activate them — they’re plugged up by caffeine’s unique shape and chemical makeup. With those receptors blocked, the brain’s own stimulants, dopamine and glutamante, can do their work more freely — “Like taking the chaperones out of a high school dance,” Braun writes in an email. In the book, he ultimately likens caffeine’s powers to “putting a block of wood under one of the brain’s primary brake pedals”.

It’s an apt metaphor, because it spells out that caffeine very clearly doesn’t press the “gas” on your brain, and that it only blocks a “primary” brake. There are other compounds and receptors that have an effect on what your energy levels feel like —GABA, for example — but caffeine is crude way of preventing your brain from bringing things to a halt. “You can,” Braun writes, “get wired only to the extent that your natural excitatory neurotransmitters support it.” In other words, you can’t use caffeine to completely wipe out an entire week’s worth of very late nights of studying, but you can use it to make yourself feel less bogged down by sleepy feelings in the morning.

These effects will vary, in length and strength of effect, from person to person, depending on genetics, other physiology factors, and tolerance. But more on that in a bit. What’s important to take away is that caffeine is not as simple in effect as a direct stimulant, such as amphetamines or cocaine; its effect on your alertness is far more subtle.

It Boosts Your Speed, But Not Your Skill — Depending On Your Skill Set

Johann Sebastian Bach loved him some coffee. So did Voltaire, Balzac and many other great minds. But the type of work they did didn’t necessarily get a boost from their prodigious coffee consumption — unless their work was so second-nature to them that it felt like data entry.

The general consensus on caffeine studies shows that it can enhance work output, but mainly in certain types of work. For tired people who are doing work that’s relatively straightforward, that doesn’t require lots of subtle or abstract thinking, coffee has been shown to help increase output and quality. Caffeine has also been seen to improve memory creation and retention when it comes to “declarative memory”, the kind students use to remember lists or answers to exam questions.

(In a semi-crazy side note we couldn’t resist, researchers have implied this memory boost may be tied to caffeine’s effect on adrenaline production. You have, presumably, sharper memories of terrifying or exhilarating moments in life, due in part to your body’s fight-or-flight juice. Everyone has their “Where I was when I heard that X died” story, plugging in John F. Kennedy, John Lennon or Kurt Cobain, depending on generational relatability).

Then again, one study in which subjects proofread text showed that a measurable boost was mainly seen by those who could be considered “impulsive” or willing to sacrifice accuracy and quality for speed. And the effect was only seen in morning tests, indicating the subjects may have either become lightly dependent on caffeine, or were more disposed to such tasks at that time of day.

So when it comes to caffeine’s effects on your work, think speed, not power. Or consider it an unresolved question. If we’re only part of the way to understanding how caffeine effects the brain, we’re a long way to knowing exactly what kind of chemicals or processes are affected when, say, one writes a post about caffeine science one highly caffeinated afternoon.

For a more direct look at what happens to your brain when there’s caffeine in your system, we turn to the the crew at Current. They hooked up one of their reporters to a brain monitor while taking on some new caffeine habits and share their brains on caffeine:

Effectiveness, Tolerance And Headaches

Why do so many patients coming out of anaesthesia after major surgery feel a headache? It’s because, in most cases, they’re not used to going so long without coffee. The good news? If they wait a few more days, they can start saving coffee again for when they really need it.

The effectiveness of caffeine varies significantly from person to person, due to genetics and other factors in play. The average half-life of caffeine — that is, how long it takes for half of an ingested dose to wear off — is about five to six hours in a human body. Women taking oral birth control require about twice as long to process caffeine. Women between the onset of ovulation and beginning of menstruation see a similar, if less severe, extended half-life. For regular smokers, caffeine takes half as long to process — which, in some ways, explains why smokers often drink more coffee and feel more agitated and anxious, because they’re unaware of how their bodies work without cigarettes.

As one starts to regularly take in caffeine, the body and mind build up a tolerance to it, so getting the same kind of boost as one’s first-ever sip takes more caffeine — this, researchers can agree on. Exactly how that tolerance developers is not so clear cut. Many studies have suggested that, just as with any drug addiction, the brain strives to return to its normal function while under “attack” from caffeine by up-regulating or creating more adenosine receptors. But regular caffeine use has also been shown to decrease receptors for norepinephrine, a hormone akin to adrenaline, along with serotonin, a mood enhancer. At the same time, your body can see a 65 per cent increase in receptors for GABA, a compound that does many things, including regulate muscle tone and neuron firing. Caffeine, it’s been suggested, is probably not directly responsible for all these changes. By keeping your brain from using its normal “I’m tired” sensors though, your caffeine may be causing the brain to change the way all of its generally excitable things are regulated. Your next venti double shot goes a little less far each time, in any case.Photo by zoghal.

A 1995 study suggests that humans become tolerant to their daily dose of caffeine — whether a single soda or a serious espresso habit — somewhere between a week and 12 days. And that tolerance is pretty strong. One test of regular caffeine pill use had some participants getting an astronomical 900 milligrams per day, others placebos — found that the two groups were nearly identical in mood, energy and alertness after 18 days. The folks taking the equivalent of nine stiff coffee pours every day weren’t really feeling it anymore. They would feel it, though, when they stopped.

You start to feel caffeine withdrawal very quickly, anywhere from 12 to 24 hours after your last use. That’s a big part of why that first cup in the morning is so important — it’s staving off the early effects of withdrawal. The reasons for the withdrawal are the same as with any substance dependency — your brain was used to operating one way, and now it’s suddenly working under completely different circumstances. Headaches are the nearly universal effect of cutting off caffeine, but depression, fatigue, lethargy, irritability, nausea and vomiting can be part of your cut-off too, along with more specific issues, like eye muscle spasms. Generally, though, you’ll be over it in around 10 days — again, depending on your own physiology and other factors.

Getting Out Of The Habit And Learning To Tame Caffeine

Beyond the equivalent of four cups of coffee in your system at once, caffeine isn’t giving you much more boost — in fact, at around the 10-cup level, you’re probably less alert than non-drinkers. So what if you want to start getting a real boost from caffeine once again, in a newly learned, less dependent way?

Our own Jason Fitzpatrick has both intentionally “quit” coffee, as well as just plain run out of coffee. Being the kind of guy who measures his own headaches and discomfort, he suggests measuring your caffeine intake, using caffeine amounts in all your drinks, chocolate and other “boosting” foods. Wise Bread has a good roundup of caffeine amounts, and the Buzz Vs The Bulge chart also shows how many calories you’ll be cutting if you start scaling back. Once you know your levels, map out a multi-week process of scaling down, and stick to it. Jason also suggests that dependency kicking is a good time to start taking walks, doing breathing exercises or other mind-clearing things, because, in his experience, their effects are much greater when caffeine is not so much a part of your make-up.

Braun, author of Buzz, sees it the same way, but still uses coffee — strategically, according to our email exchange:

In practical terms, this means that if you’d like to be able to turn to caffeine when you need it for a quick, effective jolt, it’s best to let your brain “dry out” for at least several days prior to administration. This is actually my current mode of consumption. I don’t regularly drink coffee anymore (gasp).

This from a man who loved (and wore out) his home espresso maker. I love coffee in all its guises. But after 30+ years it wasn’t working for me. For one thing, the problem with caffeine is that there are adenosine receptors all over the body, including muscles. For me, that meant that caffeine made me vaguely stiff and sore, and it aggravated a tender lower back that was prone to spasm. But I also just wasn’t getting a clean, clear buzz from coffee…I drank so much, so regularly, that drinking an extra cup or two didn’t do a helluva lot except, perhaps, make me a little more irritable.

So about a year ago I slowly tapered down, and now I have, if anything, a cup of tea (half black, half peppermint) in the morning. (The amount of caffeine from the black tea isn’t enough to wire a gnat.) Not only does my body feel better now, my brain is clean of caffeine, so I really want (or need) a good neural jump-start, I will freely…nay, ecstatically…indulge. Then I stop and let the brain settle again.

That’s the theory, anyway…and it’s basically true, although I’ll freely admit that sometimes I have an espresso or coffee just because it tastes so damned good.

That’s our attempt at summing up the science and common understanding of caffeine in one post. There is, as you can imagine, a lot more to explore — Braun’sBuzz is a good starting point, but you’ll find your own way from there.

What’s the most interesting thing you’ve learned about caffeine, either from reading or personal experience? Share the science in the comments.

Originally published on Lifehacker Australia

Fungus Inside Us: A New Health Frontier?

Fungus Inside Us: A New Health Frontier?:

Microscope image of intestinal fungus. Image: Iliyan Iliev

The big, weird world of creatures inside you may be even bigger and weirder than anybody thought.
Fungi are the latest addition to human menagerie, joining bacteria and viruses in forming the teeming, biological kingdom-spanning superorganisms of our bodies.
“We were all fascinated with the diversity and sheer mass of microorganisms that live inside our intestines,” said immunobiologist David Underhill of the Cedars-Sinai Medical Center. “So we started asking: What do we know about fungus in the gut?”

In a June 8 Science study, researchers led by Underhill and postdoctoral student Ilian Iliev link gut fungus to colitis, an inflammatory bowel disease.
While the findings may be presently useful to colitis researchers, the implications are sweeping: Scientists might ask the same questions of internal fungi as they do internal bacteria, the importance of which is now a buzzing research frontier.
In the last decade, researchers have linked resident communities of bacteria — which outnumber human cells in a body by 10 to 1 — to diseases and fundamental processes, from diabetes and heart disease to metabolism and immune system function. Even viruses are in on the act.
Appreciation of this so-called microbiome represents a sea change in awareness of bacteria: No longer are they external entities that sometimes cause disease, but rather an essential, positive component of human health.
Whether fungi also play a part is a question relatively few researchers have asked. A handful of studies have suggested a limited role, primarily in skin and mouth conditions.

'People have understood that fungi are there, but that's been a relatively vague notion.'

“There’s not a whole lot out there at this point. People have understood that fungi are there, but that’s been a relatively vague notion,” Underhill said.
He and Iliev were intrigued several years ago by population-wide genomics studies that linked a cellular component called CARD9 to slightly higher rates of irritable bowel syndrome.
CARD9, the researchers knew, played a crucial role in the immune system’s detection of fungal cells, and mice with CARD9 deficiencies were especially vulnerable to fungal infections.
“That got us to ask: How could a signaling molecule involved in antifungal immunity be involved in irritable bowel syndrome? Is there a fungus in there?” Underhill said.
The new study represents three years of research on that question. Underhill and Iliev’s team first designed molecular probes to detect fungi in mouse stools. They found hundreds of species and then, to make sure it wasn’t a mouse-specific phenomenon, repeated the search in rats, rabbits, dogs and people.
Again and again, they found a wealth of gut fungi.
Next they engineered a strain of mice lacking dectin-1, a cellular component that interacts with CARD9 in tagging fungal cells for immune system disposal. With their fungal detection systems haywire, the mice developed severe intestinal inflammation, similar to colitis.
“We think the fungus gets into the tissue and isn’t recognized and killed,” Underhill said, and to test this possibility they dosed the mice with an antifungal drug. The mice recovered.
Underhill and Iliev then looked at genetic data from hundreds of ulcerative colitis patients seen at Cedars-Sinai. Among people with the most severe afflictions, who could not be treated and required surgery to remove their colons, they found strong links to mutations affecting dectin-1.
“I think it makes a pretty strong case that there are common fungi in the gut that are normally non-pathogenic that can cause problems if not properly managed,” said Andrew Gewirtz, an Emory University gut bacteria specialist who was not involved in the study.
Underhill warned that the findings haven’t yet been duplicated in another patient group, a necessary step in ensuring the link to colitis.
A fungal link to colitis is, however, just a first hypothesis. Underhill and Iliev’s mouse scans found some 200 fungal species, fully half of which had never been described before. Only a few species were present in mouse food, suggesting that fungi are an established part of gut communities.
“The paper is great. It raises awareness for the fungal microbiome in the gut that we know is there but somehow is underappreciated,” said Peer Bork, a bioinformaticist at the European Molecular Biological Laboratory.
Bork’s own research on gut bacteria has found global patterns analogous to blood type distributions. Whether that holds true for fungi is a now a question to be investigated, along with possible fungal roles in metabolism, immunity and other physiological processes.
“People study all that in the context of the gut bacteria, in the context of viruses in our microflora,” Underhill said. “You can map all those questions to fungi.”
Citation: “Interactions Between Commensal Fungi and the C-Type Lectin Receptor Dectin-1 Influence Colitis,” by I.D. Iliev; C.N. Reyes; C.A. Becker; M. Dubinsky; D.P.B. McGovern; D.M. Underhill; V.A. Funari; K.D. Taylor; Q. Nguyen; S.P. Strom; J. Brown; J.I. Rotter; P.R. Fleshner at Cedars-Sinai Medical Center in Los Angeles, CA; H.L. Wang; D.M. Underhill. Vol 336, Issue 6085, June 8 2012.

Small Solid Oxide Fuel Cell Reaches Record Efficiency

By Pacific Northwest National Laboratory

Friday, June 01, 2012

Pacific Northwest National Laboratory developed this highly efficient, small-scale solid oxide fuel cell system that features PNNL-developed microchannel technology and two unusual processes, called external steam reforming and fuel recycling. Credit: PNNL

Individual homes and entire neighborhoods could be powered with a new, small-scale solid oxide fuel cell system that achieves up to 57 percent efficiency, significantly higher than the 30 to 50 percent efficiencies previously reported for other solid oxide fuel cell systems of its size, according to a study published in this month's issue of Journal of Power Sources.
The smaller system, developed at the Department of Energy's Pacific Northwest National Laboratory, uses methane, the primary component of natural gas, as its fuel. The entire system was streamlined to make it more efficient and scalable by using PNNL-developed microchannel technology in combination with processes called external steam reforming and fuel recycling. PNNL's system includes fuel cell stacks developed earlier with the support of DOE's Solid State Energy Conversion Alliance.
"Solid oxide fuels cells are a promising technology for providing clean, efficient energy. But, until now, most people have focused on larger systems that produce 1 megawatt of power or more and can replace traditional power plants," said Vincent Sprenkle, a co-author on the paper and chief engineer of PNNL's solid oxide fuel cell development program. "However, this research shows that smaller solid oxide fuel cells that generate between 1 and 100 kilowatts of power are a viable option for highly efficient, localized power generation."
Sprenkle and his co-authors had community-sized power generation in mind when they started working on their solid oxide fuel cell, also known as a SOFC. The pilot system they built generates about 2 kW of electricity, or how much power a typical American home consumes. The PNNL team designed its system so it can be scaled up to produce between 100 and 250 kW, which could provide power for about 50 to 100 American homes.

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What is an SOFC?
Fuel cells are a lot like batteries in that they use anodes, cathodes and electrolytes to produce electricity. But unlike most batteries, which stop working when they use up their reactive materials, fuel cells can continuously make electricity if they have a constant fuel supply.
SOFCs are one type of fuel cell that operate at higher temperatures - between about 1100 and 1800 degrees Fahrenheit - and can run on a wide variety of fuels, including natural gas, biogas, hydrogen and liquid fuels such as diesel and gasoline that have been reformed and cleaned. Each SOFC is made of ceramic materials, which form three layers: the anode, the cathode and the electrolyte. Air is pumped up against an outer layer, the cathode. Oxygen from the air becomes a negatively charged ion, O2- , where the cathode and the inner electrolyte layer meet. The ion moves through the electrolyte to reach the final layer, the anode. There, the oxygen ion reacts with a fuel. This reaction creates electricity, as well as the byproducts steam and carbon dioxide. That electricity can be used to power homes, neighborhoods, cities and more.
The big advantage to fuel cells is that they're more efficient than traditional power generation. For example, the combustion engines of portable generators only convert about 18 percent of the chemical energy in fuel into electricity. In contrast, some SOFCs can achieve up to 60 percent efficiency. Being more efficient means that SOFCs consume less fuel and create less pollution for the amount of electricity produced than traditional power generation, including coal power plants.
Sprenkle and his PNNL colleagues are interested in smaller systems because of the advantages they have over larger ones. Large systems generate more power than can be consumed in their immediate area, so a lot of their electricity has to be sent to other places through transmission lines. Unfortunately, some power is lost in the process. On the other hand, smaller systems are physically smaller in size, so they can be placed closer to power users. This means the electricity they produce doesn't have to be sent as far. This makes smaller systems ideal for what's called distributed generation, or generating electricity in relatively small amounts for local use such as in individual homes or neighborhoods.
Goal: Small and efficient
Knowing the advantages of smaller SOFC systems, the PNNL team wanted to design a small system that could be both more than 50 percent efficient and easily scaled up for distributed generation. To do this, the team first used a process called external steam reforming. In general, steam reforming mixes steam with the fuel, leading the two to react and create intermediate products. The intermediates, carbon monoxide and hydrogen, then react with oxygen at the fuel cell's anode. Just as described before, this reaction generates electricity, as well as the byproducts steam and carbon dioxide.
Steam reforming has been used with fuel cells before, but the approach requires heat that, when directly exposed to the fuel cell, causes uneven temperatures on the ceramic layers that can potentially weaken and break the fuel cell. So the PNNL team opted for external steam reforming, which completes the initial reactions between steam and the fuel outside of the fuel cell.
The external steam reforming process requires a device called a heat exchanger, where a wall made of a conductive material like metal separates two gases. On one side of the wall is the hot exhaust that is expelled as a byproduct of the reaction inside the fuel cell. On the other side is a cooler gas that is heading toward the fuel cell. Heat moves from the hot gas, through the wall and into the cool incoming gas, warming it to the temperatures needed for the reaction to take place inside the fuel cell.
Efficiency with micro technology
The key to the efficiency of this small SOFC system is the use of a PNNL-developed microchannel technology in the system's multiple heat exchangers. Instead of having just one wall that separates the two gases, PNNL's microchannel heat exchangers have multiple walls created by a series of tiny looping channels that are narrower than a paper clip. This increases the surface area, allowing more heat to be transferred and making the system more efficient. PNNL's microchannel heat exchanger was designed so that very little additional pressure is needed to move the gas through the turns and curves of the looping channels.
The second unique aspect of the system is that it recycles. Specifically, the system uses the exhaust, made up of steam and heat byproducts, coming from the anode to maintain the steam reforming process. This recycling means the system doesn't need an electric device that heats water to create steam. Reusing the steam, which is mixed with fuel, also means the system is able to use up some of the leftover fuel it wasn't able to consume when the fuel first moved through the fuel cell.
The combination of external steam reforming and steam recycling with the PNNL-developed microchannel heat exchangers made the team's small SOFC system extremely efficient. Together, these characteristics help the system use as little energy as possible and allows more net electricity to be produced in the end. Lab tests showed the system's net efficiency ranged from 48.2 percent at 2.2 kW to a high of 56.6 percent at 1.7 kW. The team calculates they could raise the system's efficiency to 60 percent with a few more adjustments.
The PNNL team would like to see their research translated into an SOFC power system that's used by individual homeowners or utilities.
"There still are significant efforts required to reduce the overall cost to a point where it is economical for distributed generation applications," Sprenkle explained. "However, this demonstration does provide an excellent blueprint on how to build a system that could increase electricity generation while reducing carbon emissions."
For more information visit www.pnnl.gov.

Will Dark Chocolate a Day Keep the Doctor Away?

Study: Dark Chocolate May Lower Heart Disease and Stroke Risks

Reviewed by Laura J. Martin, MD

May 31, 2012 -- Should people at high risk of heart attack and strokeeat dark chocolate every day?

Maybe, according to a new study from Australia.

"Dark chocolate may be a pleasant and effective way of delivering important dietary components that can provide health benefits to the ever increasing numbers of people at increased risk of cardiovascular disease," says researcher Christopher M. Reid, PhD, professor of cardiovascular epidemiology and preventive medicine at Monash University in Australia.

Reid and his team constructed a mathematical model to predict the long-term health effects of eating dark chocolate daily in high-risk people. They did not study actual people eating actual chocolate.

The researchers also computed whether it would be cost-effective to spend money on a public education campaign about dark chocolate's benefits. They found it would be.

Several studies have found that dark chocolate, with its heart-healthy flavonols, can lower blood pressure and improve cholesterol.

However, Reid believes theirs is the first study to model the long-term effects of eating dark chocolate in reducing cardiovascular risk.

The study is published in the journal BMJ.

The History of Chocolate Slideshow

Chocolate to Prevent Heart Attacks

Reid's team first looked at the treatment effects linked with dark chocolate by evaluating studies already published.

They computed the number of heart attacks and strokes that would occur with and without the dark chocolate.

They also looked at 2,013 people from the Australian Diabetes, Obesity, and Lifestyle study. All had metabolic syndrome but none had diagnosed heart disease or diabetes at the start.

Metabolic syndrome increases the risk of heart disease and stroke. It is diagnosed when three or more of the following factors are present: high blood pressure, high triglycerides, low levels of "good" HDL cholesterol, high blood sugar, or a large waist size.

Reid's team looked at costs associated with the heart and stroke problems.

They used these cost figures to determine how much money could be spent each year to educate high-risk people about dark chocolate and still be cost-effective.

Their study looked longer-term than most, 10 years, Reid says.

Dark Chocolate to Prevent Heart Disease, Stroke

First, the researchers plugged in the best-case scenario: 100% of the people eating the recommended 100 grams of dark chocolate (3.5 ounces, or about two bars) a day for 10 years.

This would prevent 70 nonfatal and 15 fatal heart attacks and strokes per 10,000 people over 10 years, according to the study model.

With an 80% adherence rate, there would be 55 fewer nonfatal and 10 fewer fatal heart attacks and strokes per 10,000 people over 10 years.

The estimates may be low, Reid says.

They found that it would be cost-effective to spend $42 per person per year on education.

The education might include advertising, educational campaigns, or subsidies to pay for the chocolate, Reid says.

---

Other Experts Not Convinced

The new model drew mixed reactions from U.S. chocolate researchers.

"It's over-assuming the benefits," says Eric Ding, PhD, nutritionist and epidemiologist at Harvard Medical School. He reviewed the findings.

"They are basing their estimates on heart disease intermediate risk factors (blood pressure and cholesterol) and not on actual heart disease events, like heart attacks," Ding tells WebMD.

The researchers are ignoring some downsides, he says. "They are ignoring the dangers of too many calories and too much fat and sugar from the chocolate bar," he says.

Those at risk of heart attack and stroke should first focus on lifestyle, Ding says. That includes weight loss if needed, exercising regularly, and not smoking.

Joe Vinson, PhD, professor of chemistry at the University of Scranton and a long-time chocolate researcher, likes the study, even though it has limitations.

"It's all theoretical based on statistics," he says. Even so, he says, "It's wonderful news again on the health effects of dark chocolate for people who have a little higher risk [of heart problems] than the normal person."

With their doctor's approval, people at risk of heart attacks or strokes could eat a bit of dark chocolate daily and monitor their weight and blood pressure, Vinson suggests.

He recommends eating less than 100 grams used in the model. He suggests about 40 grams, or about one chocolate bar, daily.

Reid suggests that the chocolate should be dark and at least 60%-70% cocoa.

The research was supported by an Australian Research Council grant with Sanofi-Aventis Australia.

Sharp Hits Solar Cell Efficiency Record of 43.5%

© Sharp

With all of the different types of solar cells being developed from thin-film tocrystalline silicon as well as new ways of boosting light absorption it seems there is always a new solar cell efficiency record being announced, but this new record from Sharp of 43.5% is a pretty big deal. A large jump over the company's previous record of 36.9% efficiency in November 2011, it shows that solar technology is getting ever closer to that 50% mark that could revolutionize the industry.

Sharp achieved the conversion efficiency record with their concentrator triple-junction compound solar cell that uses a lens-based system to focus sunlight on the cells to generate electricity.

According to Sharp:

Compound solar cells utilize photo-absorption layers made from compounds consisting of two or more elements, such as indium and gallium. The basic structure of this latest triple-junction compound solar cell uses Sharp’s proprietary technology that enables efficient stacking of the three photo-absorption layers, with InGaAs (indium gallium arsenide) as the bottom layer.

To achieve this latest increase in conversion efficiency, Sharp capitalized on the ability of this cell to efficiently convert sunlight collected via three photo-absorption layers into electricity. Sharp also optimized the spacing between electrodes on the surface of the concentrator cell and minimized the cell’s electrical resistance.

© Sharp

Conventional solar panels that are on the market now still have an efficiency of only about 15 to 20 percent, but these breakthroughs made in labs will eventually lead to climbing efficiencies in mass market solar panels too. Sharp's compound solar cell technology is currently only used in space satellites, but the company wants to adapt the technology into small-surface-area solar cells that would be practical for use down here on the ground.

The conversion efficiency record was confirmed by the Fraunhofer Institute for Solar Energy in April 2012 and it is the same exact conversion efficiency achieved by Solar Junction of the United States in March 2011. The fact that two companies have been able to achieve the same high efficiency is a good sign that the industry is quickly scaling up efficiency across the board.

 Pictureque carving dressing the entrey to the Roseville School of Arts.

Brain Development

Disclaimer

There is a great deal of technology building up that guides practitioners in addressing childhood learning matters. Those of us laymen wishing to express an opinion on the subject need to be sure that our statements do not bring the technicians or practitioners into disrepute. Still, laymen are entitled to an opinion… so having disclosed my ignorance in the matter, let me tell you a thing or two.

Equal Starting Points

It is my belief that newborn babes have pretty-well the identical number of neurons. We all have the potential to build our allocated quotient of 100-150 trillion synapses. Arguably, heredity gives one child the propensity to build synapses in parts of the brain where forbears had well-worked skills. Arguably, some infants develop synapses at different rates; perhaps girls build theirs a little faster than boys; perhaps first-born build theirs faster because of the additional attention from parents. 

Arguably, the IQ (intelligence Quotas) tests in schools mislabelled (or misunderstood) aspects of intelligence. Does a child able to more quickly recognise a pattern have a higher intelligence than a child able to build a particular pattern? Is it nurture or nature that determines the allocation of synapses across the brain and across different types of skills? 

Academic studies give great preference to having an abundance of synapses in the skills associated with verbalising, numeracy, logic and memory. Historically, we have believed that some kids will never be capable of learning calculus, some kids will never be able to draw; some kids will never be able to run a 12-second 100 metres.  I keep an eye out for studies that claim to be able to accurately predict the boundaries of learning for each individual. If I’ve missed these articles, perhaps someone can point them out for me. 

Sugars and the Juvenile Brain

Every parent and grandparent will have observed a sensible focussed child drink a sugary cordial and within 5 minutes become an uncontrollable zombie. Each of us may have experience lack of brain stimulus (feeling bored, lethargic, uninterested) only to become an energised genius 5-minutes after our morning cup of coffee. This immediate change in brain functioning should be able to tell us a lot about the functioning of this critical organ.

Researchers are now paying greater attention to the longer-term effects of sugar on our brain function. Should we feed our kids food with high fructose contents? Should school canteens be pedalling soft drinks overloaded with sugar? (Perhaps ACCC should look at the appropriate use of the word ‘soft’ in this branding exercise.) Perhaps a more responsible approach could be to offer drinks only with coffee additives… with no sugar. 

The Teen Issue

Some researchers are forming the view that during middle to late adolescence, the teenage body clock takes a nocturnal shift. These researchers claim the propensity to sleep later and stay-up later affects all adolescents… those who have a propensity to get up early will modify their waking hours by about the same degree as those who have always had a propensity to get up late. Researchers have yet to suggest a biological or evolutionary explanation of this shift. However, the researchers claim it is useless to ignore the phenomenon… adolescent students will learn more slowly in classes that start early in the day. Arguably, their driving licenses should be restricted to driving only after 10:00AM each morning. Perhaps, parents should schedule their heart-to-heart talks with their adolescent children after 10:00PM… when they can be more likely to have their child’s full attention.

There appears to be an existing trend for schools to schedule the start of Junior high-school classes earlier in the day and schedule senior secondary school classes to start late in the day. 

Regulated Rate of Learning 

We have all suffered the stress of choosing whether to push our child to keep up with the class average in all subjects, against the view that all kids will welcome the learning experience in all skills if you just wait long enough. How hard… how early… that’s the question. Some parents argue that a very important gift to give a child is to allow them the time to grow. Let them spend their free time in unstructured distraction. If the wandering child comes across a topic that catches his/her interest, give them encouragement to follow-up. This theory assumes that sooner or later, each child will want to learn within the parameters that have caught his/her interest. 

This theory cites Einstein being unable to walk or properly talk up to the age of 3. It points to the low proportion of successful entrepreneurs with tertiary education. Bill Gates dropped out, as did Steve Jobs and Mark Zuckerberg. They point to the high rate of depression within professional academics. All good points. However, it takes nerves of steel to see your child/grandchild falling behind class in basic skills… be it reading or writing or arithmetic… and not apply some pressure to get the child to allocate more effort to learning. It gets down to basic philosophic points regarding happiness verses wealth verses contributing to society.

Learning through Different Channels

One last matter. Some kids learn through association. Some kids learn best through repetitious memorising. Some kids learn best through tactile handling objects. You may be one of those people who can remember every word of Bob Dylan’s songs but can’t remember the name of the Prime Minister in the 1970’s. 

It seems that the neurons used in singing are quite distant from the neurons used for memorising facts. Some educators encourage children having difficulty in memorising spelling lists (for example) to put the words into a song to encourage them to see the word when they sing the appropriate part of the song. The world champions in memorising lists (e.g. the sequence of playing cards in a shuffled pack) have somehow trained their mind to associate each item with a real-world object. The player memorises the objects that somehow triggers the name of the list item… beats me!

It would be great if researchers could explain how ‘ordinary people’ can use these memorising techniques, particularly school children… who currently spend inordinate amounts of times memorising lists that will not be particularly useful in later life.

The Rant is Over

Well, like any good rant, I have thrown opinions at you without any purpose and without any suggested solution. In conclusion, it shows how much more we have to learn regarding the workings (or non-workings) of our brains.

Old and New Neurons Trade Roles to Aid Memory

Brain cells help us recall the past by taking on new roles as they age

For decades researchers have known that our ability to remember everyday experiences depends on a slender belt of brain tissue called the hippocampus. Basic memory functions, such as forming new memories and recalling old ones, were thought to be performed along this belt by different sets of neurons. Now findings suggest that the same neurons in fact perform both these very different functions, changing from one role to another as they age.

Image: Illustration by Thomas Fuchs

The vast majority of these hippocampal neurons, called granule cells, develop when we are very young and remain in place throughout our lives. But about 5 percent develop in adulthood through the birth of new neurons, a process known as neurogenesis. Young granule cells help form new memories, but as they get older they switch roles to helping recall the past. Newer granule cells pick up the slack, taking on the role of helping to form new memories. Susumu Tonegawa of the Massachusetts Institute of Technology and his colleagues published the findings on March 30 in the journal Cell.

Tonegawa’s team tested the role of these adult-born cells by genetically engineering mice in which the old cells could be selectively turned off. They then put the mice through a series of mazes and fear-conditioning tests, which demonstrated that young granule cells are essential to forming separate memories of similar events, whereas old granule cells are essential to recalling past events based on small cues. This discovery suggests that memory impairments common in aging and in post-traumaticstress disorder may be connected to an imbalance of old and new cells. “If you don’t have a normal amount of young cells, you may have a problem distinguishing between two events that would be seen as different by healthy people,” Tonegawa says. At the same time, the presence of too many old cells would make it easier to recall traumatic past experiences based on current cues.

Previous research has shown that both traumatic experiences and natural aging can lead to fewer new neurons being produced in the hippocampus. But a cause-and-effect relation between impaired neurogenesis and memory disorders has yet to be established. If such a connection is found, this research will have opened the door to a novel class of treatments aimed at stimulating neurogenesis. Already it is changing the way we think memory works.

This article was published in print as "Old Neurons, New Tricks"

Drinking Red Wine Is Good for Gut Bacteria

Moderate Intake of Some Red Wines May Improve Health, Study Shows

By Cari Nierenberg
WebMD Health News

Reviewed by Louise Chang, MD

May 25, 2012 -- Drinking a daily glass of red wine not only tastes good to many people, but it's also good for the bacteria lining your large intestine.

A new Spanish study suggests that sipping about 9 ounces of Merlot or a low-alcohol red wine changed the mix of good and bad bacteria typically found in the colon in ways that can benefit your health.

Bacteria may sound like a bad thing to have in your intestinal tract, but having a balanced mix of them actually helps to digest food, regulate immune function, and produce vitamin K (which plays a key role in helping the blood clot).

Since the study results showed that Merlot and low-alcohol red wine had similar positive effects on intestinal bacteria, researchers suspect it's not due to the alcohol but to the polyphenol compounds found in the wine.

Polyphenols are helpful plant-based compounds found in a variety of foods and beverages. Besides red grapes, many other fruits and vegetables are rich sources of polyphenols, as are coffee, tea, chocolate, and some nuts.

Previous research has looked at whether polyphenols in the diet can influence the balance of intestinal bacteria. This study sought to explore whether drinking red wine can have a similar prebiotic effect. Prebiotics are substances you eat that help promote the growth of good gut bacteria.

Red, Red Wine

In this small study, which appears in the American Journal of Clinical Nutrition, researchers followed 10 healthy middle-aged men. For the first 15 days of the study, the men had no wine or other alcohol. This was followed by three 20-day periods in which the men were given one of three beverages to drink each day: They received either 9 ounces of Merlot, 9 ounces of low-alcohol-content red wine, or about 3 ounces of gin.

Unlike the red wines, gin contains no polyphenols, so it served as a comparison.

Throughout the study, volunteers were asked not to change their diets or exercisehabits. They were also told not to drink any additional alcohol. Blood, urine, and stool samples were collected from each man during all four study periods. And their weights and blood pressures were monitored.

The findings showed that the balance of intestinal bacteria shifted in the men in a similar way whether they drank the Merlot or low-alcohol red wine. In both cases, they had a larger percent of certain beneficial gut bacteria.

After drinking the polyphenol-rich beverages, the men also had lower blood pressure. It also decreased triglyceride levels, HDL cholesterol (the so-called goodcholesterol), and C-reactive protein (CRP) levels, a measure of inflammation.

"This study was the first to show that regular, moderate consumption of red wine could have a noteworthy effect on the growth of select gut microbiota," the researchers conclude.