Oct
15
2007
On February 9, 1971 Edgar Mitchell (along with Alan Shepard) as part of the Apollo 14 mission walked on the moon. Astronauts are the rock stars of space exploration. The Apollo missions were genuinely hazardous and required a tremendous amount of physical prowess, skill, and training. So Mitchell deserves respect as a true and brave hero.
Unfortunately, this also means that whenever Mitchell utters anything controversial, no matter how absurd, the press will be there to report on what this astronaut says – primarily because they can then run a headline that reads “Astronaut Says.”
Here is a recent example, “Astronaut: We’ve Had Visitors.” Now, reading this headline you might be tempted to think that this astronaut (Mitchell) is revealing some first hand knowledge of NASA’s involvement with aliens – and you would be wrong. You might also assume, recklessly, that the astronaut has some new evidence to back up these claims, and again you would be disappointed.
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Oct
11
2007
Take a look at the spinning girl below. Do you see it spinning clockwise or counter-clockwise? I see it spinning counter-clockwise, and I had a hard time getting it to switch direction. Give it a try.
These kinds of optical illusions are always fun. What they reveal is how our brain processes visual information in order to create a visual model of the world. The visual system evolved to make certain assumptions that are almost always right (like, if something is smaller is it likely farther away). But these assumptions can be exploited to created a false visual construction, or an optical illusion.
The spinning girl is a form of the more general spinning silhouette illusion. The image is not objectively “spinning” in one direction or the other. It is a two-dimensional image that is simply shifting back and forth. But our brains did not evolve to interpret two-dimensional representations of the world but the actual three-dimensional world. So our visual processing assumes we are looking at a 3-D image and is uses clues to interpret it as such. Or, without adequate clues it may just arbitrarily decide a best fit – spinning clockwise or counterclockwise. And once this fit is chosen, the illusion is complete – we see a 3-D spinning image.
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Oct
10
2007
Gee, I really hope not. That would be tragic. Brain tumors are no fun and the idea that something as useful and commonplace as cellphones is increasing the risk of brain tumors is very disturbing. But my personal preferences aside (even if they are likely to be representative) this is one of those important questions that can and should be answered by a dispassionate, careful, and systematic look at all the evidence.
So far the answer appears to be – probably not, but we’re not sure. More study is needed.
But science is not easy, and a seemingly simple question such as – “do cell phones cause cancer?” turns out to be very complex. Exploring this complexity (much of which is common to any such question) is a good place to start, and also can provide a guide to thinking about such questions in the future – and such questions are likely to be endless in our increasingly technological society.
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Oct
09
2007
Occasionally scientific medicine takes a leap forward by discovering a new technology to address an entire category of disease. The development of antibiotics to treat and vaccines to prevent infectious diseases is probably the most stunning historical example. Prior to antibiotics the treatment for infectious diseases was supportive, or simply ineffective. Now they can still be very serious, but most are treatable and even curable.
One category of disease for which there is still no cure is genetic diseases. Most genetic diseases can be treated only with supportive care. Some can be significantly mitigated – for example phenylketonuria is a genetic disease resulting in the inability to metabolize phenylalanine, resulting in the buildup of toxins that damage the brain. Brain damage can be avoided, however, by screening at birth and then a very low phenylalanine diet for those affected. The progress of some genetic diseases can be slowed by treatment, and for many others only symptomatic treatment is available. There is no treatment, for example, that significantly alters the course of any muscular dystrophy.
Genetic counseling is available, once a history of genetic disease is known, and this may allow the prevention of passing on genes for severe genetic illnesses. Essentially you can choose not to have children to avoid passing on a bad gene.
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Oct
08
2007
A member of the SGU forum asked the following question:
I have a daughter that I love so much. But since I can not afford 20 more children and probably will only have one more, I would like to have a boy baby (Specialy my mom) hehe … many books on internet / and even doctors claim that they can help couples choose a certain gender. Is that a scam or can we really choose our next baby’s gender?
The short answer is that it is a scam (unless we are talking about artificial insemination, which I will discuss below).
First, some basic biology. Human DNA is divided into 23 different chromosomes, with each cell having a pair of each. One of those chromosome pairs are the sex chromosomes – which come in two flavors, X (female) and Y (male). Females have two X chromosomes, and males have one X and one Y. Eggs from the mother and sperm from the father each contribute one copy of the 23 chromosomes. Eggs can therefore only contribute an X, while 50% of sperm with be X and 50% Y. Therefore the sperm dictates the sex of the child.
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Oct
05
2007
There has been a recent debate among science popularizers about the issue of “framing,” which refers to the strategy of explaining science in the context of the real world and what it might mean for the target audience. The belief that scientists need to pay more attention to such things comes partly out of the recognition (and frustration) that the “other side,” those who have an agenda that is not purely scientific, are very good at framing their message. In fact in many cases “framing” becomes a polite word for propaganda.
Those who promote the dubious and vague concept of so-called “alternative medicine” have been very successful at framing the debate and media coverage to their extreme advantage, as is evidenced by a recent CNN Health article, 5 Alternative Medicine Treatments that Work.
The very name “alternative medicine” (and also “complementary” or “integrative” medicine – which I will refer to by the abbreviation CAM) is a good example of framing for the purpose of propaganda. These names suggest that such treatments are an acceptable alternative to scientific medicine. The notion of CAM also, and quite deliberately, creates the context for a double-standard. Promoters of CAM have diligently worked to create this double-standard, one for scientific medicine, and another for CAM.
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Oct
05
2007
The Skeptics Guide to the Universe now has an official blog – The Rogues Gallery. There are seven authors, myself included, and we will post a new entry every day at 8:00am Eastern. Give it a look.
I posted today’s blog entry over at the Gallery, answering a listener’s question about intelligent design.
Oct
04
2007
I am a practicing neurologist in CT, which is practically at the epicenter of Lyme disease in the US (in fact, the disease is named after Lyme CT where it was first described). So I have seen my fair share of Lyme disease and a form a late Lyme disease known as chronic neurolyme. It is without a doubt a real and serious disease. However, it is also the basis for what I consider to be a fake disease, chronic Lyme. I was therefore very happy to see an excellent article in the New England Journal of Medicine critically analyze this troublesome fake syndrome.
Throughout history there has always been a number of popular fake diseases or syndromes – although the specifics have changed over time. Sometimes the disease is completely fictional, like electromagnetic hypersensitivity. Sometimes the diagnosis is really just a name being applied to a laundry list of non-specific symptoms, like “asthenia,” (a diagnosis popular a century ago). And often the fake diagnosis is based upon a real disease but overextends the diagnosis to incorporate those without the specific symptoms of the disease but who have nonspecific or vague symptoms. In this latter category I would place chronic fatigue syndrome, fibromyalgia, and chronic Lyme.
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Oct
03
2007
As further evidence that the internet is a double-edged sword, the following comment was left on a previous post:
Dr. Novella,
Thanks for this information. I’m writing because one, I’d like to commend the NESS and your podcast for the work its been doing in bringing a rigorous debate on science, pseudo-science, and outright quackery to the public and two, being in the healthcare field such as yourself, I’m simply amazed at the nonsense the media shovels out to the laypeople because I’m seeing the results of the hysteria and paranoia first hand in the ER where I work.
I just received this email from my father this am and he was absolutely convinced that this procedure to help “rescue” a person suffering a stroke would work.
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Oct
02
2007
Northern Nigeria has seen more than its fair share of polio in recent years, a disaster completely of its own doing. It has made itself into a poignant object lesson in the risks of anti-science and conspiracy theories. Even worse, the world is paying for Nigeria’s irrationality.
Trouble started in 2003 when rumors began to spread in northern Nigeria that the polio vaccine was deliberately tainted to cause AIDS, cancer, and infertility. The local government conspired with religious leaders to spread these rumors and shut down the vaccine program.
Up until that time the Global Polio Eradication Initiative was very successful in distributing vaccines to poor parts of the world and achieving a high compliance. So successful was the program that experts began to predict that total eradication of polio was just around the corner.
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