Cancer is Depressing

I don’t think the observation that cancer contributes to depression would win any awards for profundity, it’s likely such news would put a crimp in anyone’s day. Indeed, the very fact that the news of cancer itself can influence our emotions  makes it difficult to examine the contributing factors toward depression in those suffering from cancer. Our ability to foresee our own possible demise and react emotionally to it confounds attempts to tease out the strands of cause and effect. Approximately 10% of cancer sufferers are diagnosed with clinical depression and up-to two thirds experience some sort of mood disorder.

In order to separate out the effect of conscious knowledge of the disease from the psychological symptoms researchers have to turn to rats. How do you tell if a rat is depressed? To find out the scientists monitored the rat’s Twitter and Facebook pages for negative statements, no actually the rats are subjected to a swimming test, the longer the rats floated in the water without trying to escape the more depressed the animal is. The researchers found that rats with cancer showed signs of depression but not other behaviours normally associated with sickness, implying the rats were not simply feeling unwell.

Analysis of the rats tumours, blood and brain showed an increase in specific cytokines that have been linked to behavioural changes. In other words the presence of the tumour triggers changes in the brain that influence behaviour. This means that depression could be considered another symptom of cancer and not merely a by-product of knowledge of the cancer. This could have implications for how we treat depression in cancer patients and help them deal with the side-effects, simply knowing that being depressed is not something under their own control might itself be helpful.

Fringe Science on TV

Tomorrow (Wednesday 1/07/09) is the NZ premiere of Fringe on TV2 8.30pm. As a keen science fiction fan I have already seen the entire first season and highly recommend it, with one caveat, and I can not stress this enough, Do Not Think about the SCIENCE on this show. Seriously, it took me quite a few episodes to take this advice myself, there are concepts and statements in the show that just make you want to stick your head in the microwave a la “The Happening” if you don’t just let it flow over you, like a refreshing breeze of nonsense. One particularly egregious pronouncement from Walter, the main “Scientist” on the show was something like “Applying Occam’s razor, the simplest explanation is that the boy is telepathic”, these simple words had me trying to claw my way out of my own brain to escape the stupid

Those familiar with arguments in pseudoscience, including but not limited to: UFOs, Cryptozoology, faith healing and evolution denial, recognize that one of the most misapplied principles of critical thinking is “Occam’s Razor”. The trouble is that it seems so reasonable to those putting the argument forward that they carry along with them the otherwise reasonable people that hear it. If someone claims to be hearing voices and subsequently seems to know things that under normal circumstances they couldn’t know, the simplest explanation is not telepathy. Unfortunately inserting a fantastic and unsupported claim into a problem does not “simplify” things.

The simplest explanation of lights in the sky is not alien spacecraft, it is much more likely that the observer has failed to identify a mundane phenomena than it is that aliens have crossed the unimaginable distances between the stars using exotic physics that allow them faster than light speeds and are wandering around the countryside in our lower atmosphere cruising for a good time. It certainly takes less thought to arrive at aliens than it does to exhaust every other possible source for the lights but this in and of itself does not make it simpler

All that being said, if you can withstand the intellect destroying abuse of science as portrayed in Fringe then do by all means watch it. The interaction between Walter Bishop, brilliant scientist and one time psychiatric patient, and his son Peter is alone a large part of the enjoyment to be had from the show and well worth the many gaffs made by the writers in an attempt to string together a plot. I won’t attempt to dissect the show and point out the many inconsistencies with reality and how the world really works, this exercise has been done in much more depth than I would be able to muster for the project. I’ll simply point you there instead.

Episode:1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20

Project Implicit

Are you sexist? Have a tendency to think that women should stay out of science? Do you prefer the company of straight people over that of gays? Like whites more than blacks? In these enlightened politically correct times it is socially unacceptable in most circles to answer yes to many or all of these questions (depending on where you live). Some will deny that they would answer yes to any of these questions but privately do so, while others will deny even privately that they would. That is to say I might publicly decry the attitudes portrayed in the above questions and even consider myself to be tolerant and unbiased while still holding the views subconsciously.

This is where Project Implicit comes in. Project implicit attempts to uncover the unconscious attitudes of those that take the test and in the process learn something about human nature. The tests are devised in such a way that categories under study have both positive and negative words associated with them in turn. Thus you end up with four alternatives: Gay/Good, Gay/Bad, Straight/Bad, Straight/Good. Once these associations are stipulated the subject is timed in their ability to adhere to these groupings when the positive or negative words are flashed on a screen. When a positive word flashes when the Gay/Good:Straight/Bad pairings are active the subject must hit a key to assign it to the Gay/Good category and conversely when a negative word is flashed assign it to the Straight/Bad category. Each participant must complete testing rounds covering all four possible pairings, after which the amount of time it took to assign each word is tallied and the implicit bias determined.

The underlying assumption of the tests is that people with a preference for one set of pairings, say Gay/Bad:Straight/Good will respond faster than with the reverse pairings. This is meant to indicate the extra processing time required to artificially group the categories. In other words, using less politically charged groups, a combination of Natural/Food and Artificial/Buildings will seem more natural and be easier to assign the words apple, grass, rocks, airplane, computer, garage. In which case participants will do this task faster than the more unwieldy categories of Natural/Buildings and Artificial/Food (ok perhaps in this age Artificial/Food isn’t so unusual but you get the idea).

Can human attitudes be “tricked” into showing themselves in this way? The researchers think so and a mounting pile of scientific papers seems to back them up. I certainly recommend at least taking a few of the “Demo” tests, the results may surprise you. Approximately 30% of respondents register strong preference for whites over blacks or straights over gays so there is a good chance of falling into those categories despite your own expectations. The website even has a warning before the tests are administered: “In reporting to you results of any IAT test that you take, we will mention possible interpretations ……. If you are unprepared to encounter interpretations that you might find objectionable, please do not proceed further.” For some reason the words of Yoda and Luke are brought to my mind:

Luke: There’s something not right here… I feel cold. Death.
Yoda: That place… is strong with the dark side of the Force. A domain of evil it is. In you must go.
Luke: What’s in there?
Yoda: Only what you take with you.

New BlogRoll Links

Just got around to updating my Blogroll with new links to New Zealand blogs and a couple others of interest, so check them out at the bottom of the page…

Fast Thoughts are Happy Thoughts

Ever noticed that when you are excited or happy your thoughts seem to zip hither, thither and yon at a dizzying pace? Perhaps at the same time you also had feelings of increased energy, creativity and self esteem. These are all symptoms of the psychiatric condition of mania, but you’re probably fine. The persistent linking of mania with rapid thoughts has lead some researchers to suspect that the speed of thought itself, and not necessarily the content of those thoughts, has a direct effect on a person’s mood. Thus merely thinking at a faster pace can create a more positive mood, along with those other symptoms, I mean normal feelings, of creativity, energy, etc.

With this approach as their starting point psychological scientists Emily Pronin and Daniel Wegner, of Princeton and Harvard University respectively, conducted an experiment to elucidate the exact effect of thought speed on mood, independent of the contents of those thoughts. To this end they recruited a number of students to read statements aloud at different speeds, the statements were either fast and positive (eg ‘‘Wow! I feel great!’’) or fast and negative (eg ‘‘I want to go to sleep and never wake up’’) and were contrasted with the reverse combinations, slow/positive, slow/negative. The results showed that the speed of a person’s thinking does indeed have an impact on their mood independent of what they are thinking. Those who read depressing statements fast had a more positive outlook than those who read the depressing statements more slowly.

This work has implications for the treatment of both mania and depression, having manic patients work to slow down their thought processes or those suffering depression increase the speed of theirs might be a more sustainable and empowering (for the patient) method of treating the conditions. Not to mention how this might affect business brainstorming sessions, want to boost your team’s creative output? Just get them doing quick mental exercises to get their brains in the mood. Have some bad news to give? Say it really fast.

Evolution Survey

Just a quick post to spread the word about a survey covering the public acceptance of evolution in New Zealand and the effect (if any) of religious/spiritual beliefs on the the extent to which evolution is accepted in the wider community. The survey can be found Here, and the results will be presented around November 2009.

The survey is being conducted by Drs Marc Wilson and Peter Ritchie of Victoria University in Wellington. I hope to secure an interview with the two Drs closer to the release of the data to get their views on the implication of the findings. In the mean time go participate in the survey, it will only take a few minutes and will be time well spent.

Man Flu, the Disappointing Reality

Man Flu, scourge of modern Manly life. Struck down by this dreaded disease men are reduced to a shadow of their former glory, unable to maintain the meager level of household responsibility they usually get away with or even care for their own well being. Reduced to mewling invalids, men afflicted with Man Flu have little recourse beyond bed rest and watching daytime television while a significant other tends to their every need. After being ridiculed by wives and girlfriends for decades science has come to the rescue and vindicated us, the Man Flu exists!*
*The preceding is a work of fiction and any resemblance to real people or events is coincidental.
Despite what the media would have us believe recent advances in scientific research has not in fact established that Man Flu is a real phenomena beyond simply showing our inability to deal with sickness effectively. The real science behind the hype, as usual, is much more modest in it’s scope and consequences.

So what was actually studied? The research was carried out by McGill University in Canada and looked at the effects of a certain protein, caspase-12. The study involved investigating how the activity of this protein affects immune response against Listeria monocytogenes bacteria, a microbe that can cause serious food poisoning, in mice. Part of the study also investigated the effect of gender on the activity of the protien and whether any difference was mediated by the hormone oestrogen. To do this researchers infected mice with the bacteria and looked at spleen and liver bacteria levels in male and female mice with and without the gene for the protein and male mice with the gene and being treated with estrogen. 

The interesting thing is that this gene did have a different effect on how sick the mice got depending on the presence or absence of estrogen. Those male mice with the gene were more susceptible to the infection than females or males recieving hormone treatment, but the gene is inactive in most humans. Only about 20% of native Africans have a working version of the gene, so this research has virtually no applicability to general differences in flu severity between men and women. I guess Man Flu remains a myth, for now.

Folic Acid Fortification, a extra tidbit

It seems topical to discuss folic acid fortification as it has recently been in the news and by the end of the year it will be a legal requirement that breads contain approximately 135µg of folate per 100g. I will actually not wade into the debate directly, fortuitously a study was published mid last month on one of the potential benefits of folate supplementation. The study looked at the effect of supplementation on the number of very preterm births and found that it had a protective effect.

First a little background might be in order, Folic acid is one of the B vitamins and is important in cellular metabolism. As a vitamin it is a nutrient that we must obtain through our diet. Food stuffs such as leafy vegetables and liver (mmm, liver) are good sources of folate however it is still a part of our diet that tends to be lacking. Because of this many western countries now mandate fortification of grain products with the vitamin. This is because of the important role it also plays in pregnancy and in particular the prevention of Neural Tube Defects, notably Spina bifida.

The study looking at folate supplementation and preterm births found that the important factor seemed to be duration of supplementation prior to pregnancy rather than the dosage of supplementation. In particular durations of greater than 12 months seemed to be most beneficial. However as the study was undertaken in the US the supplementation was taking place in conjunction with an existing fortification of bread products, this implies that the fortification alone was not sufficient to prevent all preterm births and that women that are planning pregnancies should continue to supplement with folate even after fortification is introduced.

In addition the folate supplementation was self reported by the women in the study at enrolment and after pregnancy had begun rather than being proscribed prior to attempts to conceive. This seems to mean that we must rely on the memory of the women to be accurate regarding the duration of supplementation. Despite this limitation there still seems to be a good correlation between supplementation and reduction in preterm births. Bottom line appears to be that supplementation in addition to fortification is a good idea for the childbearing among us.

Bird Dance

What do you, parrots and the ability to copy sounds you hear have in common? Well, apparently dance. A cockatoo named Snowball has been helping to shed light on rhythmic movements in animals and it’s connection to the capacity for vocal learning. The idea here is that our predilection for boogie has it’s roots in the tools we use to learn to speak. Vocal mimicry is a basic prerequisite for learning speech as you need to be able to co-ordinate your own muscle movements with sounds you hear in order to produce them yourself. This means that animals that have the capacity to mimic sounds are good at synchronizing movements to external stimuli, or keeping the beat.

As parrots tend to be known for their ability to reproduce a wide range of different noises including human speech it is reasonable to expect that they too might be moved by the rhythm. It turns out that this does indeed seem to be the case, Snowball apparently has a favourite song, “Everybody” by the Backstreet boys, to which he bobs his head and lifts his feet and sways side-to-side. To test whether Snowball was actually dancing to the beat or simply moving without any relation to the music this song was manipulated to change the number of beats per minute and played back to Snowball to see if he could match his movements to the new tempo.

While Snowball’s performance wouldn’t win any dance competitions there were enough periods where his movements synchronize with the music to show that he wasn’t just dancing by accident. While this sort of research might help us understand the development of music and dance in humans it may also have more practical applications in treatment of degenerative disorders such as Parkinson’s Disease which may be helped by giving patients an external stimulus to synchronize their movements to. What do you know, dance is good for something.

Here you can watch Snowball rock on,

Further reading:

http://vesicle.nsi.edu/users/patel/Patel_Iversen_Bregman_Schulz_NYAS_in_press.pdf

http://www.foxnews.com/story/0,2933,518494,00.html

How Soon is Now?

Do you experience “Now” at the same time as I do? It follows, as a direct consequence of having bodies that perceive and interact with the world using chemical nerve signals, that we don’t experience the world directly. Whenever we see, touch, hear or otherwise sense our environment we are experiencing the world as it was a split second ago, the time required for signals to move around the body and then get processed in the brain to generate our sensation of living in the world is small but real. This also means that our brain has to work to synchronize all of the disparate signals into a coherent whole, this means there is a delay built into the system to allow for all of the signals to arrive before allowing the perception to filter into our conscious awareness.

One of the additional consequences of this process is that your perception of “now” may depend on how tall you are. After a little thought this becomes obvious as the signals from the end of a tall person’s leg will arrive at their brain after a longer period that that of a shorter person. This delay is actually further exacerbated by the fact that as nerve cells get longer they also tend to get thinner, and thinner nerves carry signals slower than thicker ones. Studies have shown that a signal will travel 0.27m/s (metres/second) slower for every extra centimetre.

Putting this all together means that the in-built delay that allows us to experience a synchronized picture of our surroundings must be longer for tall people than for everyone else. Or in other words, their “now” is later than my “now”, and mine might be later than yours. So if your larger companion seems a little slow on the uptake, don’t be too hard on them, it’s just the way they are wired.

Change of blog layout

Those of you who tend to see the main page of this blog might notice a minor change to the layout. I’ve started using the “More…” function for the posts so this page doesn’t run on forever. Might also give me a better idea of how many actually interested visitors I get.

If anyone prefers the other format just leave a comment.

Voting with a Look

At their most influential levels elections can have the power to change the world, witness the sweeping changes that the new American president has ushered in. As a result those candidates that we elect are chosen based on careful consideration of all the issues, reflection on their policies and an understanding of the impact that will come about based on those choices. Or are they? We all like to think that we make these decisions as rational thinking adults but recent research may call that certainty into question. A study published in February this year and conducted by John Antonakis and Olaf Dalgas at the University of Lausanne in Switzerland looked at election results by using children. Specifically they showed children pictures of election candidates in the French parliamentary elections as part of a game. At the end of the game the children were asked which person they would prefer to captain their boat. The children’s choices accurately matched the outcomes of the actual elections.

Friend or Fantasy?

We all seem to enjoy immersing ourself in fictional worlds, whether your preference is for the technophile’s utopia of Star Trek or a trashy romance novel, there are few among us who don’t enjoy at least a brief sojourn away from reality. We take it for granted that we can separate the two experiences, reality vs fantasy, but how do we really tell the difference? According to an fMRI study published in PLoSone, the key might be in how we judge things to be relevant to ourselves. In real life we interact with people and acquire a large multifaceted body of information about them from where they live to their favourite colour and how they like to have their coffee. In comparison the fiction characters we are likely to encounter we may generally only experience in a very narrow way, in the context of the story.

VAERS Data: A Comparison

My two regular readers are probably sick to death from hearing about a certain HPV vaccine by now but I thought I’d put up a quick comparison of VAERS data for those that are interested.

The raw VAERS data is quite popular among those who wish to cast aspersions on the safety of the vaccine so I thought I would query the database myself to see what the results would be and compare the Gardasil figures against less controversial vaccines. I decided to compare the data for all reported adverse events between the time 2006-2009 for not only the HPV quadrivalent vaccine but also the flu vaccine and the MMR vaccine. If Gardasil is so dangerous the figures should be significantly higher for this vaccine than the others shouldn’t they?

Gardasil Follow-up: The Evil Toxins

My last post on Gardasil has garnered quite a bit of interest so I thought I would follow it up with a look at some of the other claims about this vaccine that are also geared towards warning women away from it. The focus of this entry is, as the title implies, the ingredients of the vaccine and their alleged toxicity. Now I would first like to make clear that I am not trying to argue that these compounds are not at all toxic, that would be an untenable position almost anything is toxic at the right (or wrong) dose. This brings up the heart of the issue though, the dose is key here, the claims by detractors of the vaccine imply that the amounts of the chemicals in the vaccine are above the toxic threshold. I, along with the medical community so I feel I’m in good company, consider this to be an incorrect conclusion.