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Apr 29
Blink
Image by ballookey via Flickr

Not that this has anything to do with anything, but the average human blinks close to ten million times a year, roughly 800 hour’s worth of shut-eye whilst remaining awake. If as a triathlete you were to train this much each year, you would likely perform better on race day. The moral of the story? Open your eyes and get training.

This quote is form Chuckie V. blog. He is a triathlon coach, and former pro triathlete.

Are we blinking our life away ?

His joking quote got me thinking, 800 hours a year that is a lot of blinking. What would you do if you were given 800 free hours each year to do anything you want?

(first I wanted to do a quick check on his calculations. Blink rate: range of 2-30 per minute with the average often quoted as 10. The average blink takes 300-400 milliseconds - so for fun say 350ms average. Therefore, per minute are eyes are closed in blink 10 x 350ms = 3,500ms. Since 1,000ms = 1 second on average are eyes are closed 3.5 seconds out of each minute. Assuming being awake 16 hours a day and sleeping 8 hours I calculate 56 minutes each day is lost to blinking, and hence 340 hours each year - but this is for a 10 per minute blinker. Maybe Chuckie blinks at slightly more than 20 per minute, which would put him in the range of 800 hours each year :)

Being an easily distracted neuroscientist I had actually read a few articles about some neuroscience behind blinking. While we might all know that the function of blinking is to lubricate the eye, there is at least another level to the story.

Blinking rate correlated with cognitive flexibility:

One theory suggest that people who have a high blinking rate have better cognitive flexibility, but decreased cognitive stability (easily distracted) when compared to those with a lower blinking rate (Dreisbach et al., 2005). Levels of prefrontal cortex dopamine is thought to be involved in blinking rate (though like any interesting science there is some controversy). The general thought from previous papers is the higher the level of dopamine the higher the rate of spontaneous eye blink.

But beyond just blinking of the eyes, is there a brain blink (I know sounds a bit crazy), and are the two blinks related?

Attentional blink:

If two things are presented at a fast rate (sounds like our modern digital world) there might be a reduced ability to detect the second thing presented if the time between them is too short (between 200 - 500 ms). Meaning that most of us have no problem if the time between presented objects is longer than 500ms. So even if your eyes don’t blink your mind blinks and you may miss rapidly presented information. Dopamine is also thought to be involved in the attentional blink - interesting (Colzato et al., 2008). Previous work had found that a shorter attentional blink (AB) is correlated with better working memory (Arnell et al., 2008, Colzato et al., 2007). Think of a shorter AB meaning you can detect two objects very close in time - meaning your attentional blink was not screwing up your recognition of the two objects.

Even more interesting is that Colzato et al., (2008) found that eye blink rate predicted the mind’s attentional blink. Subjects with highest blink rate had a smaller attentional blink (in this case a smaller attentional blink is a good thing). As an aside, there was a fair bit of variability in spontaneous eye blink rate - in this study ranging from around 2.4 to 31.8 blinks per minute (see above eye blink calculations).

The authors argue that higher prefrontal cortex levels of dopamine is related to higher blink rates, shorter attentional blink times, and better working memory.

Take home:

But Chuckie would of course tell you this all comes at a cost - you are ’sleeping’ away your life with all that blinking. And at least Dreisbach et al., 2005 might tell us there is a cost to the high dopamine, high eye blinking rate and this is maybe these people might be prone to be easily distracted (though there are many variables including the amount and type of dopamine receptors and the exact task being tested - so hard to draw any firm conclusions. Fascinating field of research but not straighforward).

Maybe Chuckie is on to something, if you want to be a focused athelete a high blink rate with its easy distractibility and all those lost hours each year would be deterimental to your training, and hence performance. Maybe a slower cow like blink rate and a dedicated focus on putting in the hours of training is the likely key to success. You have to put the hours of work in.

But of couse this was mainly a light hearted post. But don’t waste your life - either by ’sleeping’ it away, or by being too easily distracted.

Open your eyes and get out there and do something with your life.

Apr 28
Photo of Terry Fox, Canadian cancer fund-raise...
Image via Wikipedia

I tell this story to bring up the idea of hope, even if unfounded, may have potential value.

Terry Fox is a true Canadian hero. However, I am not sure how many people from outside Canada have heard of him. In the summer of 1980 he set out to run across Canada to raise funds for cancer research. Terry lost one leg to cancer at the age of 18, but had beat cancer and he wanted to give something back.

Three years later on April 12th 1980 he started his ‘Marathon of Hope‘ at the opposite end of the country from where he lived by dipping his leg in the Atlantic ocean in St. John’s Newfoundland. His plan was to run a marathon a day as he crossed Canada (8,000+ km, 5,000+ miles) in the direction toward home in Vancouver and try to raise at least 1 million dollars. His final physical goal was to dip his leg in the Pacific ocean in Victoria, B.C..

My summer of 1980:

I had somewhat a unique perspective on Terry Fox’s run. Two months after the start of Terry’s run, in June of 1980 I was diagnosed with cancer at the age of 18. My testicular cancer had spread into several regions of my body, including a football size tumor in my abdomen, along with a grapefruit and two smaller orange sized tumors in my chest cavity. I am a fairly slim person so with a football in my abdomen there wasn’t a lot of room for the rest of the organs. The only reason I even went to a doctor was I couldn’t really stand much more than 30 minutes at a time without what felt like my kidneys hurting so much I had to sit down.

My first afternoon at the Vancouver cancer clinic they told me I had cancer (after doing a small biopsy of one of my tumors in my neck region (lymph gland) and started chemotherapy within two hours of stepping into the clinic. Wow, that seemed awful fast at the time. They informed me I had stage 4 cancer and that I had a less than 5% chance of surviving.

p < 0.05

The funny thing is when the doctor told about less than a 5 % chance of living I never ‘heard’ this statement. Even though my parents stood behind me when the doctors layed out the reality they heard them perfectly fine. It wasn’t until some 10 months later after I was out of the woods and the doctors retold me how serious things had been (and later my parents recounted to me the story of the doctors clearly stating I had less than  a 5 % chance) that this information registered in me at a conscious level. Obviously, I blocked out the reality of what the doctors were telling me. And maybe this was the best thing for me. I was 18, closing in on 19 shortly, I didn’t even think it was possible for me to die. You know how many young people are - they don’t think they are ever going to die.

Less than 5% probability of surviving, and this was the projected estimate despite the fact that on average doctors overestimate (overly optimistic) about their patients chances (Christakis and Lamont, 2000: “Overall, doctors overestimated survival by a factor of 5.3″ (but this was not just cancer patients), Glare et al., 2003). I find it a little ironic many years later that 5% is of special significance for me as a scientist, with all scientists chasing the almighty p < 0.05. I ignored the 5% probability at the time and now, like every other scientist, my career largely depends on finding that p < 0.05 (however meaningful these numbers are is a subject of another debate).

Terry’s run:

Terry Fox made progress in his run across Canada, but initially he did not get much media coverage nor did he raise much money. In Vancouver he was covered on the news since we was from the Vancouver region. But despite all this he continued running a marathon each day, on his one good leg and his prosthesis.

But coverage and donations started picking up when Terry hit Ontario. On July 11th he had covered 3,523 km and reached Toronto and was greeted by a huge number of supporters. The country was rallying behind the young brave man.

Terry had this to say:

“…everybody seems to have given up hope of trying. I haven’t. It isn’t easy and it isn’t supposed to be, but I’m accomplishing something. How many people give up a lot to do something good. I’m sure we would have found a cure for cancer 20 years ago if we had really tried.”

Watching Terry:

Each night that I was well enough I would watch the news update of Terry Fox’s progress. I was not having as much success as Terry. My tumors had not shrunk despite the heavy doses of chemotherapy - they hadn’t shrunk one iota. I still had a football size tumor in my abdomen and a grapefruit and a couple small oranges in the chest cavity, intertwined with my heart and its blood supply.

The chemotherapy was pretty harsh. It started with 4-5 days of constant vomiting and steadily got worse with each treatment (2 days of IV chemotherapy treatment separated by 3 weeks of no treatment). By the 4th dose of chemotherapy the nausea and vomiting lasted for the entire 3 weeks. I couldn’t keep anything down for more than 10 minutes. Even straight water I would vomit up within 10 minutes. Twice I was brought into the hospital to get an IV just for the fluids. Basically, I don’t think I digested any calories for the entire 3 weeks. When I finally returned to the cancer clinic I told them I didn’t think I could handle another dose. They agreed (though I am not sure if they didn’t have other reasons to agree with me), and started me on a different ‘lighter’, less effective chemotherapy. My tumors still had not shrunk at all. Maybe at this point the doctors had given up hope and figured no use making me suffer any more.

With the ‘lighter’ chemotherapy I was able to eat again. One week later feeling much better I was in town and had to cross a street. A car came speeding forward so I figured I better break into a jog. As I took my first step I thought I was going to collapse to the pavement my legs felt so weak, but I made it across the street and avoided slowing the car down. I weighed myself that day, after a week of regular eating, and weighed in at 108 pounds, so my wild guess is that I had to be pretty close to 100 pounds at my lowest. Before starting my chemotherapy I weighed 137 pounds. I was literally a bag of bones - that is what will happen if you don’t eat for 3-4 weeks (and you start out pretty slim).

September 1, 1980:

While I was not fairing well things became far worse for Terry.

Terry Fox was forced to stop his run for his original bone cancer had metastasized to his lungs. I still vividly remember Terry announcing the news to all of us from a stretcher behind an ambulance as he got ready to fly back home to Vancouver. He had run 5,373 km (3,339 miles - which would have been enough to cross USA) averaging 23.3 miles per day - all on one leg.  A huge telethon occurred 8 days after Terry was forced to stop his run and the entire country rallied behind his cause. 10.5 million dollars was raised in a single day (by February 1981 $ 24.17 million had been donated to the Marathon of Hope).

Terry underwent interferon treatment (the latest magic bullet for cancer at the time), and chemotherapy to try to treat his cancer. However, the overall consensus was that Terry did not have a good chance to survive. It was almost a forgone conclusion that he would not survive.

My September:

My friends and family worried about how the news of Terry would affect me. Terry was a young man and it sounded like he wasn’t going to make it so why would I be any different? Of course I had still not taken in the 5% chance of survival from the doctors nor how Terry’s situation reflected on the general reality of dying. And in reality things had gotten worse since then, since I hadn’t responded to the best course of strong chemotherapy. No shrinkage of the tumors and the surgeons could not operate on that size of tumor - there was no use in even trying. Additionally, a few complications had cropped up. My one lung was only working at 20% of the normal level. They had to do a small surgery to do a biopsy of lung tissue. They first thought it was due to the chemotherapy, but later concluded it was likely due to croup disease, which I had several times as a very young child (even with one lung working at 20% later in my life I did manage to run a marathon and complete an ironman event).

At the time there was nothing positive to grab hold of for hope - but I still did. Now I will leave out a bit of the story since I have only told 3-4 friends in my entire life this part, so it is not something too easy to talk about.

Long story short, to the surprise of the doctors suddenly the tumors started to shrink. A few months later I had the major abdominal surgery in which they cut me from one side of my abdomen to the other (and part of the my side). It left a nice upside down happy face scar on my abdomen (and the lost of Rectus abdominis muscles on the right hand side below the lesion). Despite telling me that I might not be able to ejaculate after the surgery (which proved to be incorrect), and ignoring even if I could ejaculate that I would unlikely be able to father a child, they never even raised the possibility of storing sperm for this purpose in the future (which you might have read happened with Lance Armstrong, and I presume most others in our ‘modern’ times - depending on medical coverage).

26 years later: (not a ‘relaxed’ photo)

I beat the p < 0.05 odds:

Against the odds by the very early spring of 1981 it looked like I had beat cancer, if you ever can really say that. The doctors with big smiles told (retold) me how at the beginning they thought I only had  a 5% chance of surviving, and this time I heard them, but that I had beat the odds. Sure, in the subsequent years I had to go back for a couple more major surgeries to remove growing benign tumors. The surgeries nicely added to my war scars tracing my body, that decorate’ my torso.

Terry:

On June 28th 1981 Terry Fox died. Each and every year in September there is a Terry Fox run to raise money for cancer research. Worldwide over $ 400 million dollars have been raised in Terry Fox’s name. Beyond the millions of dollars raised for cancer research Terry has been an inspiration for untold millions of people with cancer. It would be hard to find a bigger everyday hero in the fight for cancer.

Conclusion:

Terry Fox is a hero in the truest sense of the word. He was an inspiration to me and millions more. I got to see some of his Marathon of Hope from the hospital bed of a cancer ward in the summer of 1980. Was it fair that I survived and he didn’t - no. Sadly cancer is not fair.

I surmise a large part of my survival came from rejecting the possibility that I was going to die. Even though the doctors clearly stated to me the reality of the situation, that I had very little chance of survival, I totally ignored them and assumed I was going to live. I grabbed hope, optimism, even when none was offered.

But I am sure the same could be said about Terry and many others. Most grab and hold tight to any hope there is. Terry was full of hope and that inspired him to try to make a difference. But hope is not always enough and that is why we have to continue the fight to find newer and more effective treatments for cancer.

But I do wonder how much hope plays a role? Now it is a very delicate and ethically troubling question of how much hope one should offer to patients. It is a fine line between between not telling the full truth and offering false, unrealistic, hope, and not offering enough hope. And all of this can largely depend on the patient and how they ask the questions. And no matter what the doctor and other health care personnel say the patient might not really ‘listen’. I will talk more about the delicate issue of hope and patient care in a soon to be posted piece.

In memory of Terry Fox.

See also:

The neuroscience of hope

Cancer over the last 50 years

Lance Armstrong comeback to raise funding and awareness for cancer research

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Apr 23

Is redder, more oxygenated, skin judged as healthier, more desirable? Does the ability to detect a healthy cardiovascular system influence our choices of potential mates? Was our retinal system under evolutionary pressure to detect the oxygenation level of skin? Is the evolutionary importance of the signals presented by healthy oxygenated skin one of the foundations of the cosmetic industry?

Good skin blood flow and oxygenation is dependent on the underlying health of the cardiovascular, hormonal, and circulatory system. The detection of good blood flow in the skin is particularly noticeable in the face, and prominent in the cheeks. Hence, the general healthy look of rosy red cheeks we have all observed, and heard about. Evolution, being what it is, could it be that rosy red cheeks are used as a predictor in primates for a health, and hence a good mate choice?

Stephen et al., 2009 examined this exact issue. In their introduction the point out the various research that indicates the link between skin redness color and underlying ‘vascular’ health:

In humans too, skin redness caused by skin vasodilation and
vascularisation has connections to physiological status including
health. Additionally, blood oxygenation state is related to health
status and affects skin colour. In women, increased sex hormone levels
are associated with increased skin vascularisation [9] and vasodilatory
response [10], which arterializes the blood in the skin [11]. The
cutaneous vasodilator system becomes more responsive with physical
training [12], but is impaired in type 2 diabetes [13] and hypertension
[14]. Increased blood oxygenation is associated with increased
aerobic fitness [15] whereas increased blood deoxygenation is
associated with hypoxia and can lead to cyanosis (blue tinted skin),
which is indicative of coronary and respiratory illness [16].

Hence, it appears there is some validity to the idea of a healthy glow. Now in general the color red, not only in skin color but in any object, is associated with being vibrant and lively. But more particularly do humans pick up and judge people with redder skin as healthier, and more desirable?

The researchers hypothesis was that increased blood color in the face will be judged as healthier and oxygenated blood color would be considered healthier than deoxygenated blood color.

(side note: human oxygenated blood is 98-99% saturated with oxygen, deoxygenated blood is around 75% oxygen saturated)

First the scientist wanted to test if oxygenated skin blood color is judged as healthier than deoxygenated blood color. Subjects were presented with faces with varying degrees of oxygenated or deoxygenated color. These Caucasian faces (or later different ethnic faces), which were presented, had been transformed to match ‘redness’ of empirically collected data from oxygenated vs non-oxygenated faces. The subjects then were asked to alter the images (via photoshop like manipulation) along two axis - they could add ‘oxygenated’ color, or ‘deoxygenated’ color and their instructions were to ‘make the face as healthy as possible’.

The subjects were not told that these two manipulations were oxygenated and deoxygenated color.

Results:

The paler the faces the greater the increase in redness (both oxygenated and deoxygenated) was added by the subjects to make the faces look healthy. If the faces were already quite red (oxygenated) then less redness was added by the subjects. Hence, the faces which appear to have the least skin blood perfusion (pale) the greatest degree of redness was added to optimize the appearance of health.

While face pictures of both sexes were altered to increase redness,  more oxygenated color was added to female faces and more deoxygeneated color added to male faces (in comparison). The authors suggest that females faces are more ’sensitive’ to blood oxygenation color - but I am not sure what they really mean.

Overall, oxygenated blood color adding was judged as improving the look of healthiness compared to added deoxygenated blood color adding. This was consistent with the researchers hypothesis - but also makes sense in the general concept of a healthier look is judged by degree and amount of oxygenated blood is reaching the face (sign of a healthy cardiovascular system).

In an additional component of the study, the researchers found that participant ethnicity, or face ethnicity, did not result in any differences in the amount of color changes added by participants to optimize a healthy appearance. However, there was an interaction effect, with African participants adding more redness to African faces than the other faces. The authors did not offer much of an explanation for this finding.

The researchers conclude from their study:

The healthy appearance of faces is enhanced by increased blood
colouration in this study, suggesting that participants interpret skin
blood colouration as a cue to underlying health. This is consistent
with the established relationship between skin blood perfusion and
physiological status. Increased vasodilation and vascularisation of
the skin leads to increases in skin blood colour. These processes are
enhanced by increased levels of sex hormones in women [35], and
by physical training [36]. Skin blood flow is reduced in patients
with hypertension [37], type 2 diabetes [38], senescence [39] and
in smokers [40].

Beyond the idea that us humans use skin color to detect the underyling health of our fellow humans, the authors suggest their might be various levels of evolution going on:

Indeed, it has been suggested that the maximum sensitivities of the medium and long wavelength cones in the retinas of routinely trichromatic primates (a group which includes humans) are ideally suited for identifying small changes in blood perfusion and oxygenation in the skin of conspecifics [43]. The results of the current study suggest that the ability to perceive health cues provided by skin blood perfusion and oxygenation may be an additional advantage of trichromatic colour vision in primates.

(43: Changizi MA, Zhang Q, Shimojo S (2006) Bare skin, blood and the evolution of primate colour vision. Biol Lett 2: 217–221.)

This part seems like a stretch for me, that our retinas specifically evolved to detect healthy mates. Though I appreciate beauty as much as everybody else it seems to me there were many other important evolutionary pressures in retinal evolution (to find and catch prey, and avoid being prey as just a few important examples) other than to detect beautiful-health. But if further research indicates that skin color detection was so important that it fundamentally affected the evolution of our retinal system - well then praise beauty.

Out of curiosity I took a look at the abstract they cited (Changizi MA, Zhang Q, Shimojo S (2006)):

We investigate the hypothesis that colour vision in primates was selected for discriminating the
spectral modulations on the skin of conspecifics, presumably for the purpose of discriminating
emotional states, socio-sexual signals and threat displays. Here we show that, consistent with this hypothesis, there are two dimensions of skin spectral modulations, and trichromats but not
dichromats are sensitive to each. Furthermore, the M and L cone maximum sensitivities for routine trichromats are optimized for discriminating variations in blood oxygen saturation, one of the two blood-related dimensions determining skin reflectance. We also show that, consistent with the hypothesis, trichromat primates tend to be bare faced.

Okay, they have examined it at a reasonable level - though I am sure others in the field could come up with alternative points of discussion. I will be dig deeper - all in the name of evolution and beauty.

(strange thought: maybe you could see if individual differences in the ability to detect degrees of face coloration is related to specific ‘coloration’ gene polymorphisms. If true it would scare me a bit).

Stephen et al., give their summary paragraph at the end of the paper:

In the current study, we show that colour associated with skin blood
perfusion and oxygenation affects the healthy appearance of
human faces. Attractiveness, thought to signal underlying health
[60,61], and strongly related to perceived health [60] is a major
factor in human mate choice, particularly by men [62]. It is likely,
therefore, that the enhanced health appearance associated with
increased skin blood colour and oxygenation colour has consequences
for attractiveness and mate choice.

Take home message:

All of this really comes down to humans may use skin color/tone - rosy red cheeks - as a measurement of blood flow/oxygenation which is an indicator of general health. We would judge the rosy red cheeked faces as more desirable. Then this evolutionary desirability of health gets transformed in our higher language as beautiful / handsome, and a host of other similar words. But most biological signals are subject to manipulation. For how long have humans pinched their cheeks to bring about a rosy complexion? Moving onward to various natural substances that could be rubbed lightly on the cheeks. And from this a whole industry of ‘blush’ makeup was founded, and still flourish probably to the tune of multiple millions of dollars every year. Well instead of spending all that money on blush one could do things to increase your vascular health such as exercise. Instead of just signaling you are healthy, you could actually be healthy.

Is a healthy oxygenated skin color obtained via a healthy lifestyle not only a health hack but also a date hack :)

Apr 22
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Image via Wikipedia

Today, April 22nd, is earth day, which is meant to ‘inspire awareness and appreciation for the Earth’s environment’. Here is an earth day network link. They are asking you to take action and suggest 4 options. Go search the net for an event in your area to join others, but also make your own personal initiative.

Yesterday, I posted an article in prelude of earth day. The post was about about how an increase in the overweight and obesity level are negatively impacting the environment, and how you can take action by keeping a healthy weight, or reducing down to a healthy weight, which would benefit the individual but also the earth’s environment.

Take action (earth day network), take a step today - figuratively and literally.

Have a happy earth day.

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