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Sep 30

Yesterday, I updated my previous pieces on how heart rate variability (HRV) can give you a good measurement of your overall body health. Today, I will update my previous post on how HRV can give us a window into the health of our brain by examining a few 2008 papers.

Depression and anxiety is inversely correlated with high frequency HRV (HF HRV), which is considered a specific indicator of the parasympathetic component of the peripheral nervous system (Bleil et. al., 2008). Therefore, low HF HRV is associated with higher levels of depression and anxiety (which agrees with previous research).

To control for the environment and genetics a twin study examined the relationship between HRV and depression and found that for both current depression and a history of major depressive disorder a relationship with lower HRV. The authors suggests there are genetically associated pathways that underlies the link between depression and low HRV (Vaccarino et. al., 2008).

The other question that might arise from the above link between depression and HRV would be is there a potential to use HRV biofeedback to ‘train’ the system to change HRV and relieve depression? In a recent pilot study this is exactly what they did. After 6 sessions of HRV biofeedback spread over 2 weeks (14 depressed patients and 12 healthy controls) at the end of the study the depressed patients had lower depression scores (but there was not a depressed group that went though some form of sham treatment – hence why it is titled a pilot study). Interestingly, HRV in the depressed group was increased after training, while in the healthy group there were no changes (Siepmann et. al., 2008). This indicates that in normal subjects with  average level of HRV that 6 sessions of HRV biofeedback are not enough to raise HRV, while in subjects with low HRV (the depressed patients) the same number of sessions can increase HRV.It would be interesting to know if a longer period of training can increasease HRV in healthy congtrols.

Take home message

HRV is reduced in depression (and a number of other mental disorders) and has a genetic component, but HRV can be increased with HRV biofeedback training.

Now many of you might be wondering what the current financial crisis is doing to your financial, general, and mental health. Does financial stress have a negative effect on us via stress, and can it be measured by HRV. I don’t know the answer but I am guessing if it occured over long term the financial stress would negativley impact our health.

Sep 29

I have written about one heart rate measurement, heart rate variability (HRV) previously (here and here). HRV is a good measurement of both brain and body health.

The funny thing is I read about HRV 20 odd years ago while reading ‘Chaos’ by James Gleik. This book had a large influence on my science thinking, even though at the time I was just an unemployed bum who had never even attended university. Later I became interested in HR measurements in general regarding endurance training. Then by pure chance an associate of mine that studies spinal cord injury was measuring HRV in spinal cord injured humans. This re-sparked my interest in HRV and it is a fascinating topic that has many real world applications for everybody (at least a easily measured indicator of overall health of both brain and body).

Over the next few days I will update my previous two HRV posts with some more recent research.

What you have to need to know for background (if you don’t read the previous two posts) is that HIGH HRV is good, low HRV is bad (in general).

Even young subjects with diabetes have lower HRV compared to healthy age matched controls (Javorka et. al., 2008). If this effect is seen in young subjects I would only imagine it gets worse with age.

Examining 1,041 subjects researchers found that people with metabolic syndrome (1 step down the road towards type II diabetes) had lower HRV than controls (Min et. al., 2008).

High frequency HRV (driven by the parasympathetic system) was reduced in obese patients with myocardial infarction compared to non-obese myocardial infarction patients (BMI greater or equal to 30, which a very percentage in developed countries) (it was previously shown that in general obese patients have lower HRV). Interestingly, waist circumference was a better correlate to reduced HRV than body mass indies (BMI). This better link with waist size with reduced HRV could be tied into an increase of visceral fat (Piestrzeniewicz et. al., 2008).

In a Swiss study examining 1,712 randomly chosen subjects 50+ years old, from another bigger study, the researchers report that HRV is lower in obese subjects. HRV was higher in normal weighted subject that exercised (2 or more hours per week) (compared to normal weighted subjects that didn’t exercise), but also HRV was higher in obese subjects that exercised (compared to those that didn’t) (Felber Dietrich et. al., 2008).

Take home message

Diabetes, metabolic syndrome, and obesity all lead to a lower HRV (which remember is a predictor of shorter lifespan). However, even in obese subjects if they exercised they improved (increased) their HRV. My suggestion is by measuring your HRV (by first establishing a baseline measurement then following it over the years) you might be able to catch something (pre metabolic syndrome, pre diabetes, a harmful weight gain  (even though for this one we have easier measurements)) before they reach too far and take appropriate steps to improve your HRV (e.g. exercise and diet choices).

Tomorrow more about how HRV measurements can give us a window into the mind.

Sep 26

I talked a couple weeks ago about a possible fun way to increase brain health by increasing your novelty is to start a brainstormers club with your friends (related story: walking book club). And the last 3 or 4 days I have talked about information. So when you combine the two you get Google’s new 10 to the 100th power project.

Well now is the perfect time to start that brainstormer club to do some good in the world. Many of us have been faced with coming up with a ‘good’ idea by not having the time (or expertise) to implement the idea and hence the project dies.

Google is now running a contest to come up with ideas that help the world. The project is called 10 to the 100 power. Google is ready to put up $ 10 million toward this project.  Up to 5 final projects will be funded and implemented. This has nothing to do with the individual coming up with the idea making money, and all about ideas and solution to problems that will help people. So if you sat down to have a brain storming session (or rethink some old ideas) you could not only do some good for your brain (by giving it a good workout) but also, at least potentially, benefit other people.

A good little weekend project.

Deadline is October 20, 2008 – so get going.

I know I am working on writing up 2 to 3 of my ideas that I either would never find time to implement, or not the right personaltiy/skills to complete the projects. I also plan to get together with some friends this weekend to try to come up with some new ideas.

Sep 25

The last two days I have talked about information overload, and a few tips to deal with it.

Now I will introduce what I think might be the next step in news aggregators. The next wave of the net and information in general is the semantic web (web 3.0). I think silobreaker is a great example of this new wave. I don’t know if it will become the next Google, but I can tell you it is a different experience using it. It reminds me of when Google came out – search became different. In the cases of silobreaker there is a steeper learning curve – but there appears to be something there.

Here are two reviews by people that know what they are talking about compared to me: infotoday and beyond search.

Beyond search had this to say about silobreaker:

  • The system is more than six years old with significant investment in information retrieval research and productization
  • The purpose of the system is to go beyond traditional search and aggregation engines with what is called “relational analysis”.
  • The indexing is able to generate “contextual insight”. If you opt to use the results list, these are relevant and filtered with more data available with a mouse click. No visit to the search box is required.
  • The system recognizes people, companies, topics, places and keywords; understands how they relate to each other in the news flow, and puts them in context for the user.
  • The system can handle a range of content; for example, public content and a licensee’s own information

To get the full power of the site and to personalize you have to sign up (just like all the other sites). Here is what you gain.

Registration is free, simple and provides many benefits, including (from silobreaker site):

  • Access to all content (you will get only the last 30 days if you’re not logged in)
  • Access to personalisation features. Set up windows within Silobreaker with content that interests you. Drag and drop to control the screen layout.
  • Access to our User Interaction Center. Here you can request content, identify entities and lots more to help make Silobreaker even better (coming soon).

I will have to play around with this site more but the possibilities are there.

On a side note after having some more time to play with Yotify I am less enthusiastic than my initial impression.

Sep 25
Insulin-like growth factor 1

Image via Wikipedia

Calorie restriction (CR) (reduced calories with adequate nutrition) in multiple organisms increase mean and maximum lifespan. The big question (along with CR mimetics) is will it do the same in humans?

One mechanism (of many) that is thought to be involved in CR effect on lifespan is the lowering of IGF-1. It was an open question of does CR reduce IGF-1 in humans. Now we know the answer, CR by itself does not appear to reduce IGF-1 levels in humans. However, strict vegans do have lower levels which researchers thought might be tied in to their low consumption of protein (10%) (as people on CR consume over 20%). They next found convinced serveral humans following CR to reduce their protein levels to the same level and found IGF-1 levels were reduced. Interestingly, Ouroboros recently covered the potential use of vegetarian diet instead of CR because it might be easier to follow that CR.

thanks to all the following sources (and for further coverage click away).

Futurepundit coverage

longevitymeme

sciencedaily

But remember IGF-1 pathway is only one of a number of pathways (and ever growing it seems) that is altered with CR and therefore not having the same effect between mice and humans for this one pathway does not answer if CR will have a longevity effect in humans.

Sep 25

Yesterday I talked about information overload, so today I figured I might offer some practical tips that might help deal with information overload (though I am always looking for more tips and ideas to deal with this problem).

In the past I would go visit several websites stupidly typing the appropriate key word(s) into google, because sometime it was faster than going through my many bookmarks. But bookmarks are useful if you appropriately organize them (and don’t have a biziilion).

The power of personalized home page sites

I then made the leap 2-3 years ago to a net aggregation site, or what is called personalized home page sites (for a review of the many options check this out). When I used the term personalized home pages I am not talking about a blog or info about yourself, but rather a site where you get personalized delivery of information. Google reader, netvibes, myyahoo, and pageflakes are some of the most popular ones. I somewhat randomly choose netvibes as it was new at the time I started.

The use of a personalized home page has made a big difference. No longer am I searching for the many  websites I visit (be it through google or my bookmarks) and individually visit each one. All those websites come up on my home page. I immediately see if there are any new content on the various sites (based on different colored headlines). What use to take me 45min to 1 hour I can accomplish in under 15 minutes (and that includes the speed reading of new content). Now my friends will argue, somewhat correctly, is that I just use those saved 30 to 45 minutes to search for more info to consume. But either way this is increased efficiency (as measured by data consumed per minute).

The power of personalized homepages for scientists

What scientist who are familiar with the idea of personalized home pages but not active users might not now about these sites is you can set it up to get feed from Pubmed on whatever key words you choose. I have a certain tabbed page (you can have many tabbed pages in netvibes) for my pubmed science searchers. I used various key words to feed me my daily quota of my specific subfield in neuroscience. This way I don’t have to go to pubmed each day and seperately type in the various search terms. I wake up go to netvibes, click,  and whoola the latest papers titles are staring me in the face. This makes it far easier and quicker to keep up with the latest science info.

One of the next leaps to deal with info

Now of course there are many more ways to try to deal with the diluge of information but here is one that I am going to try out next. Yotify is the name of the site. Now the concept of this site (and other sites, but again this is the latest greatest at the time I am adopting this concept) is instead of having various websites that you constantly visit, you use key words/terms and ‘scouts’ are sent out to search and report back to you constantly. Scouts can be specified for shopping, fun, travel, and news/blogs. Don’t know how this will work out, it may lead to too much info – but again it should keep you up to date and expose you to info sites that you are not currently reading. I am guessing that the best that I discover using this approach over time would be added to my personalized home page.

If any of you readers have any tips or thoughts on how you deal with the information age please leave a comment or email me directly.

Have a good high information day (with reduced noise).

Sep 24

I discussed last week the information revolution and how we have near infinite access (in the developed nations) to information. It is possibly the age of infobesity.

I read a great deal on a very wide range of topics each day, then I go scouring around trying to find links between these wide topics. And as you might suppose with near infinite information you have a pretty good chance of finding at least some links. Are these possible connections just spurious – a simple numbers game? I once read about a word (which of course I can not remember now) that means the mental disease of finding connections between things when they do not exist. I should add this to the growing list of information revolution diseases along with infobese (if I could only find that word again in this mass of info).

Now I have a reason behind bringing up this concept for in our modern age as many (if not most) of us face this problem of information overload. We have to make daily choices on what information to pay attention to, what information to value and trust, but also what information to save or bookmark.

In the past our brain evolved an attention system to decide what in the environment to attend to (I am sure you can imagine many possibilities so I don’t have to give examples). But in our current time we have to worry less about attending to potential rewards (eg. food) or predators out in the environment. Instead we have to make decision on what information we should consume. Therefore, in our current time we have far more things competing for our attention than say in the caveman era. Sure we can decide to live under a rock and ignore the information world, but most of you reading this have obviously decided to continue to venture forth into the info world (since you are reading a blog). It will be interesting to see how our old attentional system, with help from higher cognitive cortical areas, survive/thrive in this new information jungle.

I know that currently I have many topics I want to blog about. I also am realizing that most of my blog pieces are too long for the normal attention span of the infobese era. That I should write short little pieces with a link and end it there. But my old ways keep propping up in that I want to try to piece things together into a somewhat bigger picture. In reality the net seems to have shortened our attention span (maybe the first adaptation (or at least one option) to info overload).

I found it very interesting that the novelist Neal Stephenson, who has written several novels in the 1,000 page range, said regarding his current attention span in his recent Wired interview:

“It’s harder for me even to read books than it used to be, and there’s an obvious irony there.”

So what are some other options to deal with this information deluge? A few options are we can filter (various technological options), use web 2.0 (friends suggestions), or try to eat the entire internet. The later can lead to indigestion.

I will be interested in hearing what the readers solution (coping mechanism) to this problem. Share with us all.

A case study

One example of the amount of info out there and the inability to consume it, all even after using various filtering mechanism is my recent 4 months off of work. I store various scientific and other sources of info on my laptop. On the average day I consume the ‘just’ of many papers and articles but do not fully read them all (say I read 3 full scientific papers, but I have skimmed and saved another 10). One of my hopes for my time off was to fully digest these saved up info sources. I really thought I could do this. And sure I did consume some of them, but in reality could not make even a meaningful dent in my backlog of readily accessible info sitting on my laptop. I also feverishly worked at distilling various diverse sources of info (compulsion to find the links and try to make a bigger picture of all the info – it truly is a disease) and made some headway – but as usual more question propped up than answer.

What I learned that I didn’t know before is that I will never catch up – there will always be more that I want to read than I am able to – no matter how much time I take off. This has been a meaningful lesson for me. What are my options? Be more selective in my info? What?

Okay the blog piece has once again become too long and this time I didn’t even tie things together. Ah – the age of info, the age of infobese. Maybe I need to go on a diet.

Sep 23
Image representing 23andMe as depicted in Crun...

Image via CrunchBase

There has been some interesting advances in personal genomics recently which is great news, but will the rise of cheap personal genome scanning result in improvement in our health?

Price is one limiting factor for lack of adoption of personal genome scanning and its potential to lead to better health treatments (pharmagenomics). Just a few months ago the standard price for the current generation of a personal genome scan (examining 500,000 to a 1,000,000 SNPs) was $ 999, but now one of the companies 23andMe has dropped their price to $ 399. This price range makes the technology available to a larger audience (but like any consumer electronic device if you can hold off another 6 months to a year things will even be cheaper – or you will get more for the same price). This story was covered by PIMM and thinkgene.

What is also interesting is Sergey Brin (co-founder of Google) has started his own blog and discusses his personal genomic scan results (his wife is the co-founder of 23andMe) (further covered by thinkgene,

Additionally, there are reports of further potential advances in the speed and price of DNA scanning. Pacific Biosciences is suggesting that they will be able to read the entire human genome in 15 minutes at the doctor’s office (see story here, thank BZ for the tip). Video of the technology (will be of interest to the molecular biologist reading this).

So either now, or in the near future more and more of us will have access, and own (hopefully), the data of their personal genome. With this we are promised as a society great advances in coming up with new treatments for various diseases and also the personalization of treatment (pharmagenomics). However, there are people such as Dr. David Goldstein who in this NY times piece argues things are not that simple (additional coverage by thinkgene). Dr. Goldstein says:

“There is absolutely no question,” he said, “that for the whole hope of personalized medicine, the news has been just about as bleak as it could be.”…“After doing comprehensive studies for common diseases, we can explain only a few percent of the genetic component of most of these traits,” he said. “For schizophrenia and bipolar disorder, we get almost nothing; for Type 2 diabetes, 20 variants, but they explain only 2 to 3 percent of familial clustering, and so on.”

The reason he gives for the failure of these large genome scans to find useful gene variants to account for various diseases is:

that natural selection has been far more efficient than many researchers expected at screening out disease-causing variants. The common disease/common variant idea is largely wrong. What has happened is that a multitude of rare variants lie at the root of most common diseases, being rigorously pruned away as soon as any starts to become widespread.

Then he goes on to talk about his own disbelief in the lack of results that researchers have come up with so far.

It takes large, expensive trials with hundreds of patients in different countries to find even common variants behind a disease. Rare variants lie beyond present reach. “It’s an astounding thing,” Dr. Goldstein said, “that we have cracked open the human genome and can look at the entire complement of common genetic variants, and what do we find? Almost nothing. That is absolutely beyond belief.

He adds:

If rare variants account for most of the genetic burden of disease, then the idea of decoding everyone’s genome to see to what diseases they are vulnerable to will not work, at least not in the form envisaged.

Of course his fellow scientist disagree with him (that personal genomics will lead to great advances in the treatment of diseases) — and we will have to wait and see which two competeing thoughts are closer to the truth.

What do you think?

Sep 22

Why would a non-vegetarian try to defend vegetarianism? It is a pure coincidence that I had the idea for this blog piece a couple days before David Foster Wallace died, and my piece on him mentioned his essay of ‘Consider the lobster’ (free audio download, text of his essay). So when I listened to his essay on the lobster while running I figured I should write it up.

Well first let us look at the main arguments in favor of vegetarianism

1) 1) Ethical

I won’t touch this – but rather self evident – but your conclusion depends on your beliefs.

2) 2) Health

This is an open argument. Some research has suggested that vegetarianism is healthier than most of the alternatives, but many other would disagree. Some data (here) suggest that there is a health advantage, but the other side I am sure would provide many papers that failed to find differences and suggest that in many cases it is unhealthy (lack of complete protein, Vit B12, etc) but also point out to the difficulties in following vegetarianism to optimize health (get complete protein, etc). And all this is not to mention other versions of vegetarianism such as vegan.

But I would think that any diet that encourages more consumption of fruits and vegetables would be better that they typical food eating pattern followed in developed nations.

One diet that seems to show consistent health benefits is the Mediterranean diet (Based on “food patterns typical of Crete, much of the rest of Greece, and southern Italy in the early 1960s”, this diet, in addition to “regular physical activity,” emphasizes “abundant plant foods, fresh fruit as the typical daily dessert, olive oil as the principal source of fat, dairy products (principally cheese and yogurt), and fish and poultry consumed in low to moderate amounts, zero to four eggs consumed weekly, red meat consumed in low amounts, and wine consumed in low to moderate amounts…The principal aspects of this diet include high olive oil consumption, high consumption of legumes, high consumption of unrefined cereals, high consumption of fruits, high consumption of vegetables, moderate consumption of dairy products (mostly as cheese and yogurt), moderate to high consumption of fish, low consumption of meat and meat products, and moderate wine consumption”). This freely available meta-analysis paper is the most recent paper I could find showing overall health benefits of this diet (reduction in overall mortality, reduction in mortality from cancer and cardiovascular disease, and reduced incidences of Alzheimer’s and Parkinson’s diseases). One thing in common between the Mediterranean diet and vegetarianism is the high consumption of fruits and vegetables.

3) Environment

Simple fact that has been widely pushed to the public since the 60′s that an acre of land can grow X amount of meat or 8-21X times more plant based food. So if you are worried about people starving (though in reality the poverty/starving problem is not about the inability to grow enough food – but rather a distribution of wealth), and/or the environment there is sound fundamental biological (and physics) reasoning why eating more plant based food uses up less land and energy. Each jump up the food chain there is a huge loss of efficiency (e.g. 21 lbs of plant based protein has to be fed to cattle to produce 1 lb of meat protein, other animals typically consumed are more efficient than beef and settle around 8 to 1 ratio). Can we in the modern world of a serious energy problem afford this 10:1 loss.

Another source breaks down the total energy input compared to the energy output (consumable calories).

Ratio of Energy Input to Food-Energy Output
Lamb 57:1
Beef cattle 40:1
Eggs 39:1
Swine 14:1
Dairy (milk) 14:1
Turkey 10:1
Chicken 4:1

Corn 1:4

I think you get the picture, and have heard this general physics/biology very large loss of energy any time you convert idea before.

Does this mean you have to become a vegetarian to play your role in reducing energy waste? I don’t things are necessarily that simple. Similar, to the decision to ride or walk to work (which I have discussed here and here) it doesn’t mean you have to do this 5-7 days a week, or never drive. You would still be contributing if you bike to work 3 or 4 days a week. You have to be practical. Say on Friday you are meeting your friends coming in from out of town further north than your work place. It might make overall sense to drive to work that day and then head out to meet your friends, instead of backtracking home (south) then re-drive back north in the direction you just came from (as one made up example). There are of course thousands of reasons to choose driving, all I am arguing is while being practical try to reduce your driving when you can.

Well the same can be said about vegetarianism, it doesn’t have to be all or none (unless you are choosing vegetarianism based on moral/ethical reasons – then it is more difficult). You can choose not to eat meat the majority of time. Say for example you are over at new friends, or maybe some similar situation, and they have prepared a meat based dinner – then go ahead and sit down to a friendly dinner. Actually it could be argued this might be the best health option. With the occasionally meat consumption (one a week or every 2nd week, whenever) might make the vegetarianism protein/nutrient balancing problem easier to deal with. You get those nutrients that are hard to come by on the vegetarianism diet by your occasional meat consumption. This would also be closer to the Mediterranean diet (since there is meat consumption on this diet). And when you do choose ‘meat’ try to pick the healthier options (fish, lean turkey, chicken over the beef choice).

I encourage you all to either read or listen to David Foster Wallace ‘Consider the lobster’ essay.

Additionally, here is a link to Mr. Wallace’s 2005 Kenyon commencement speech – something to ponder.

Take home message:

Reduce meat consumption to improve your personal energy debt (footprint), it doesn’t have to be an all or nothing choice: bike more than drive, eat plants more than meat.

Sep 19
$100 eLibrary

$ 100 e-library

Image by camera_obscura via Flickr

Novelty is good for the brain and fueled by new information. New information can be in the form of a new environment, new experiences, but for many of us modern human it comes in the form of the written word (and spoken and visuals via audio/video).

In the relatively recent past the access to new information was limited.

Most of us they have gone through the internet revolution are amazed at the change. ‘X’ years ago the assessable information was limited to your local and school libraries, and the relatively few books and magazines you and your friends owned. Now with the internet the amount of information available is almost unlimited. Sure every book ever published is not available but as an example, for scientist (with university access) an incredible number of journals are at your finger tips (depending on what subscriptions your university are paying for combined with the newer open access journals). It is hard to believe how scientist functioned as little as ten years ago when the articles were not available at the click of a mouse (you actually had to go to the library, find the journal, then photocopy it). In reality they functioned perfectly fine – but I think we have new opportunities by linking ideas from the now readily accessible papers and coming up with new ideas that would have been difficult in the recent past.

The access to information is not evenly distributed in the world

This huge growth of information availability is still largely limited to developed nations. The information is still restricted to those that can afford computers and have the ability to connect to the internet.

Brewster Kahle below gives a talk about UNIVERSAL access to all the world information in the video below (check it out). This would be an important advance in our society. Who knows what will come out of this idea. Everybody can be educated to whatever level they desire (assuming their basic life needs are met – which is a whole other problem that constantly needs to be addressed).

[youtube]https://www.youtube.com/watch?v=pXoHC2D15hM[/youtube]

To universal access to the world’s information – an idea whose time has come.

Now with the internet, and in the near future with universal access to all the world’s information we have no excuse not to exercise our brain and improve our brain health.

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