Aug 03 2017

Chunking

brainpuzzleIf I gave you a string of digits to remember, how many do you think you could handle? For example, try to remember the number – 8945557302. That’s 10 digits. Most people can handle only 7, and there is a specific neurological reason for this. Our working memory is wired for about 7 bits of information (give or take 1-2 bits). Now, try to remember the number as 894-555-7302. That is recognizable as a phone number, and despite the fact that the individual digits exceed our bit capacity, most people can remember such numbers.

Grouping bits of information into recognizable patterns in order to make them easier to remember is a phenomenon called chunking, first described by George Miller in his 1956 book, The Magical Number Seven, Plus or Minus Two: Some Limits on our Capacity for Processing Information.

Chunking is best established as a mnemonic device. Miller and others conducted experiments to see how much chunking as a strategy could extend the limits of human memory. For example, the typical number of binary bits, such as Morse code, people can remember is 9. However, someone who understands morse code will chunk the individual bits into groupings of three, each one representing a letter. They will then group letters into words and words into sentences.  This type of chunking extended memory from 9 to 40 binary bits.

Another study involved a runner tasked to remember strings of digits, again starting with a typical digit span of 7. However, he was encouraged to chunk the digits into race times – a meaningful pattern with which he was very familiar. With a little practice he increased his digit span to 80 numbers.

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Aug 01 2017

Snake Oil 1970s Style

laetrileOn a recent post I repeated my long challenge to name any alternative medicine treatment that has been rejected by CAM proponents because of evidence of lack of efficacy. I am not aware of any. It doesn’t seem to ever happen – because alternative medicine is disconnected from evidence and reality.

As if to make my point, I came across this article on Buzzfeed about laetrile – yeah, laetrile. For those of you old enough to remember, laetrile is a fake cancer cure that was already being made fun of on Saturday Night Live in the 1970s (the original cast). I haven’t heard of this one for a while, but apparently it is making a comeback.

The story of laetrile, in addition to demonstrating yet again that snake oil peddlers are con artists, also showcases how the world has changed in the last forty years when it comes to health fraud (hint – not for the better). Continue Reading »

Comments: 9

Jul 31 2017

The Goldwater Rule Revisited

goldwaterIn 1964 Fact Magazine published an article titled: “1,189 Psychiatrists say Goldwater is Psychologically Unfit to be President!”  They were later sued successfully for defamation. This incident led the The Goldwater rule – Section 7 in the American Psychiatric Association’s (APA) Principles of Medical Ethics, which states it is unethical for psychiatrists to give a professional opinion about public figures they have not examined in person, and from whom they have not obtained consent to discuss their mental health in public statements.

This rule has held sway for the last 50 years. However, recently the American Psychoanalytic Association (APsaA) e-mailed its members to inform them that they are not constrained by the Goldwater rule. So which stance is correct?

There are two competing ethical principles at stake. The first is the ethical responsibility of professionals not to cause harm to someone else by making public statements they have no business making. This is especially true when it comes to psychiatric diagnoses, because they carry a heavy and (in my opinion) unjustified stigma. The mere fact of being a public figure does not mean that medical professionals are free to bypass confidentiality and consent to make public speculations about your mental health.

Further, psychiatric diagnoses are especially complex and subjective. In order to make a accurate diagnosis you need a lot of background information about a person, and you need some professional interaction. This should ideally be a personal examination, however watching a video of another professional conducting an examination could suffice. But even then, the purpose of psychiatric diagnoses is to guide therapy. They are still fuzzy and subjective entities. It seems profoundly unethical to turn them against an individual, and use a formal diagnosis to medicalize their personality and behavior for non-therapeutic purposes.

When dealing with politicians, it is further very difficult for professionals to filter out their own ideology or personal feelings. It becomes too easy to use the tools of medicine for political fighting.

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Comments: 184

Jul 28 2017

Should You Complete That Course of Antibiotics?

antibiotic-resistanceAs with most things, the answer is more complicated than it may at first seem.

Up to now the official answer was simple – always finish prescribed courses of antibiotics. Stopping early, it was argued, could increase the risk of antibiotic resistance. The idea is that bacteria which are a little resistant to the antibiotic will survive longer, and if they are not wiped out by completing the course, the partially resistant bugs will then reproduce, with random mutations leading to greater resistance. The antibiotics are essentially a selective pressure leading to resistance.

This makes sense, and is almost certainly true with certain chronic infections, such as tuberculosis.

A new review, however, suggests that we cannot apply this rule simplistically to all infections. It depends on the type of bacteria involved.

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Jul 27 2017

Computer-Assisted Diagnosis

It is very disheartening for me to listen to the political discussions surrounding health care. I can’t help thinking that the proposed changes amount to rearranging the furniture on the deck of the Titanic.

This is not to say that there aren’t important policy decisions at stake. It is important that everyone has health coverage, as a matter of efficiency and just compassion. However, the health care debate is often framed as an attempt to reduce health care costs. This is where the rearranging the deck furniture metaphor is apt.

There are some minor efficiencies to be gained in how we pay for health care, but that is not going to touch the real driver of rising health care costs – technology. Of course there are multiple factors, but the main one is the fact that we have the technology to deliver more care and more expensive care, and to keep people alive longer. This is combined with a culture that demands expensive care. We want MRI scans for every ailment, and the most aggressive procedures to keep our loved ones going for as long as possible.

More care and higher tech care costs more money.

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Jul 25 2017

The Speed of Commercial Jets

nasa_supersonic_conceptWhen I was about 10 my family flew to California to visit my uncle. The flight from New York to LA took about 6 hours. Forty years later a flight from New York to LA still takes about 6 hours (exact flight times vary by airline, but 6 hours is typical).

The pace of technological advance in the last century has been so fast that we generally expect everything to get faster, better, cheaper as a matter of course. So the flat commercial travel times seems to be a weird exception.

Airline travel has improved over this time. Jets have become safer and more fuel efficient. Average costs of flights have decreased by about 50%, although apparently this had more to do with deregulation than technology. It may also have something to do with the shrinking legroom in economy class. But still, why does it take me 6 hours to fly across the country?

There are a number of reasons for the flat commercial flight speeds, which make it seem that there is unlikely to be a change anytime soon.

Supersonic Flight

The first factor that most people likely consider is that we are pushing up against the sound barrier. This is partly true, but not the whole story. The Concorde, which was the only commercial supersonic jet, was retired in 2003. This was mainly because flights were too expensive and it wasn’t commercially viable. There have been no plans to bring it back or replace it.

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Comments: 24

Jul 21 2017

Homeopathy Takes a Hit in the UK and Australia

dilutionI have long considered homeopathy to be the softest of targets for skeptics, especially in the area of alternative medicine. Homeopathy is 100% pure nonsense. It is a pre-scientific magical form of medicine that has no legitimate place in the modern world.

Further, homeopathy is particularly vulnerable because most people do not know how silly it is. They think it is natural or herbal medicine, but it’s not. Homeopathy involves taking fanciful treatments and then diluting them out of existence, based on the notion that the essence of the substance will be left behind and magically cure whatever ails you.

This means that simply educating the public about what homeopathy actually is can be an effective way to reduce its popularity. Knowledge is not sufficient, however, because there is no limit to what people are capable of believing. Nonsense is rarely eradicated entirely, but we can certainly restrict it to the fringe where it belongs.

Homeopathy in Australia

In 2015 the Australian National Health and Medical Research Council (NHMRC) concluding that homeopathic treatments were worthless, and that the scientific evidence has not shown that they work for any single indication.

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Comments: 13

Jul 20 2017

Bismuth and Solar Cells

bismuth ocyodideThere is something appealing about the fact that while there was so much controversy and public debate about global warming and energy production, solar cell technology incrementally improved in the background, largely unnoticed, until it became an actual cost-effective option for energy production. There were no breakthroughs or big announcements, just a slow increase in efficiency and decrease in cost.

Slow incremental changes add up, like a conservative but reliable investment. In 1941 the first silicon-based solar cells were developed with <1% energy conversion efficiency. In 2009 we broke 25% efficiency. The current record efficiency for mass-produced solar cells is 26.6%.

While more efficiency is always welcome, this is now more than enough for most practical uses of solar cells. The solar panels on the roof of my house (which doesn’t even cover my entire available roof space) produces 100% of the energy (averaged over the year) that my house consumes. Obviously, your mileage may vary, depending on roof orientation, shading, and geographic location. I live in CT, which is hardly a sunny state, so anywhere in the US should be viable for solar energy. If you life somewhere like Arizona, it’s a no-brainer.

With many technologies there is one feature that is considered a limiting factor, or at least the most important factor, at least by the public, and tends to dominate discussion. For computers it used to be processor speed, for cameras it was megapixels. Once, however, we get to the point where these parameters are generous enough to no longer be the dominant limiting factor, we start to pay attention to other factors. Make no mistake, these other factors were important all along, they were just often neglected by the public who focused on one number.

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Comments: 17

Jul 18 2017

More on Junk DNA

Junk-VennJunk DNA, put simply, is those parts of the genome (human or otherwise) that have no known function. The human genome has about 19,000 genes. A gene is essentially a sequence of base pairs that code for a protein – there are four difference bases with each triplet being a “word” that either codes for an amino acid or tells the process of transcribing the protein to stop.

Even within genes there are noncoding regions, called introns, which have to be removed from the RNA so that the coding regions can be joined together. Between the genes there are also vast non-coding regions. Some of this non-coding DNA is regulatory and structural – it helps regulate when and how much specific genes are transcribed into proteins.

The burning question is, how much of the non-coding regions between the genes serves any function and how much is completely unnecessary, or “junk”? This is an important question for understanding genetics, but also has implication for creationists. Creationists don’t like the concept of junk DNA because it strongly implies an evolutionary history. Why would a designer sloppily insert so much unneeded junk into our pristine genome? Why are genes clogged with non-coding regions that need to be removed? So they claim that all DNA has function, we just don’t know what it is.

ID proponent Stephen Meyer, for example, said:

“For example, we predicted very early on that the junk DNA was not junk. We did that on the basis of an ID perspective. “

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Comments: 63

Jul 17 2017

The Return of Dr. Gunter

goop screen-shot-2017-07-14-at-10-31-34-amIn my last post I discussed how Paltrow and her people over at goop launched a personal attack against Dr. Jen Gunter, an OB/GYN blogger who has taken the time to point out a lot of the nonsense that goop sells. Goop has been criticized by many science bloggers and mainstream outlets for fearmongering to women in order to sell dubious products.

For some reason “team goop” did not go after Science-Based Medicine, or Tim Caulfield, or Steven Colbert – they went after one humble medical science blogger. This is particularly ironic because Gunter’s blogging career is all about empowering women with science-based information, about advocating for women’s health and autonomy. I can only suppose that goop went after her because they felt particularly stung by her on-target criticism, or perhaps they thought she was an easy target for bullying.

The irony is thickened by including a response from Dr. Steven Gundry, who takes a particularly condescending tone and actually earns the often overused description of “mansplaining.”

The result was the typical litany of alternative medicine tropes, bad logic, and bad science, wrapped in a personal attack against Gunter. But they did leave themselves wide open for poking some additional fun at them, in order to point out how intellectually vacuous and dishonest they are. Dr. Gunter just drove a Mack truck through that opening.

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