Archive for the Science! Category

Tantalizing Criticism

Posted in Reviews, Science!, Things You Should Read with tags , , on November, 2010 by melendwyr

Some of you may remember my writing of a frustrating and outraging book I’d recently read that I said I would blog about. Well, I never quite got around to it – I wrote drafts and drafts, rethinking and rewriting, but I never quite expressed everything that I found wrong with the book. Yes, there were that many things wrong.

So I’ll just say it:

The Naked Ape, by Desmond Morris, was absolutely horrifying. It started off relatively well, pointing out that the most distinctive and definitive traits of humanity were from a naturalist’s perspective not at all the things we’d most likely think of (hence the title of the book). And it does a reasonably good job of reviewing the nature of human sexuality from an ‘alien’ point of view.

But it’s also full of pseudoFreudian psychobabble, grotesque misrepresentations of associative processes, just-so stories, inaccuracies, arguments asserted without proper logical or evidentiary support, and mindless repetition of the dogmas of the times in which it was written.

I may eventually point out a few of the specific problems I had with the book, because without providing the justifications this ‘review’ is really just a slander. But that will be a subject for another day.

Familial Genetic Profiling: Get Over It

Posted in Politics and Society, Science! on June, 2010 by melendwyr

razib khan, over at his new Discover blog site, briefly discusses an article in Slate which mentions familial genetic profiling, and this guy has the following response:

The article goes to list all the law-related reasons why using this partial-match system is problematic. The bottom line is that this new expansion of CODIS searches is infringing on some rights and privacy statutes. So some laws will have to be re-written if this is all going to become legal and above-board.

The bigger message is that the government’s always going to be doing these types of law enforcement expansions in total stealth mode, and it’s up to the public and their constitutional defenders to drag such changes out into the daylight and force them to be regulated.

All I can say is: How ridiculous! If law enforcement officials have a genetic profile of a criminal, and they note that a sample taken from a crime scene is almost but not quite a match to the known profile, why in the world would we expect them not to take a closer look at family members of that criminal? We know that siblings are more likely to resemble each other than randomly-chosen strangers – should we prohibit taking photographs of criminals to protect the ‘privacy’ of their relatives who may look somewhat similar?

What exactly are we expected to expect? Laws banning cops from taking note of partial profile matches? How precisely would that protect the privacy of the innocent, especially when no information about their own DNA is stored in the computer? The similarities between siblings are only statistical, after all. Possessing knowledge about one person’s DNA does provide statistical knowledge about the DNA sequences of their biological relatives, but I cannot see how that is an invasion of their privacy, nor how using partial matches to determine avenues of investigation constitutes a violation of relatives’ rights.

If a crime victim gave a description that is vaguely like that of a known criminal with an alibi, but he had a sibling who strongly resembled him, would it be a violation of that sibling’s rights if police took note of this? We’re quite willing to accept that. Why is this different?

Is it merely that genetic profiling is new and unfamiliar?

Dresden Codak: Dark Science

Posted in Reviews, Science!, Things You Should Read with tags on June, 2010 by melendwyr

Ooh, a new DC comic!

Not as wacky or as inspired as Codak’s work usually is, but I’m grateful for anything given how much time passes between updates. Plus this is the beginning of a new series, so the use of an old and shopworn joke isn’t as objectionable as it might have otherwise been; I’m confident that high levels of surreality will again be attained. The art style, as usual, is pleasing to the eye.

Also, the particular titled parodied are quite clever. I wonder what other books could be so amusingly ‘adapted’.

Problems with Schizophrenia Comic

Posted in Medicine, Politics and Society, Science! on September, 2009 by melendwyr

See this comic.

What’s the problem? The claim that the schizophrenic aren’t more dangerous. Actually, people with delusions are significantly more likely than those without to engage in physical assault – and the problem is that it’s very difficult to predict when they’ll do so.

Obviously, given ‘sane’ individuals can be very violent too, and if a given schizophrenic has no history of violent reactions there’s really no reason to think they’ll suddenly start. But all else being equal, they’re a greater danger to others than they’d otherwise be.

I’m not even going to touch the discussion of what the causes of schizophrenia are – that topic requires more work than is suitable for this post.

Something to Keep in Mind

Posted in Science! with tags on September, 2009 by melendwyr

Remember: talking to yourself isn’t a sign of madness. Most of human “thought” is just self-referential monologue. The difference is that normal people repress the expression and don’t actually verbalize, while schizophrenics have something wrong with the internal censor that prevents the interior self-discussion from being spoken.

That scene in “Austin Powers: International Man of Mystery” where Austin’s interior monologue is spoken aloud as a consequence of cryogenic trauma? It was meant as an absurdity, but it’s more accurate than either the writers or the audience likely realized.

Thoughts on Charles Bonnet Syndrome

Posted in GIGO, Medicine, Science! on September, 2009 by melendwyr

Possibly the most important lesson that should be taken from the story of Charles Bonnet Syndrome (CBS) is that correlation implies nothing about causation and even less about etiology.

Patients with general dementia, Alzheimer’s, or strokes were far more likely to communicate seeing things that weren’t there. So if you merely look at reported population statistics, visual hallucinations would seem to be associated very strongly with brain damage.

But the real problem was that such patients were much more likely to be uninhibited in talking about their hallucinations. Older people with loss of sight but properly-working minds feared the consequences of mentioning what they saw to anyone – at least partially because of the existing association in physicians’ minds between visual hallucinations and senility – and so said nothing. And so there was no awareness of the true rate of the phenomenon.

If you look at the actual statistics – the ones collected once the stigma of CBS was reduced, physician awareness increased, and elders gently but insistently questioned – then there’s no particular association between senility or brain disease and the hallucinations.

Remember – it took hundreds of years for the condition to even be mentioned in the English language, despite all of the people who must have experienced vision loss and CBS in that time. Despite all of the physicians who must have aged or had eye damage and suddenly experienced it themselves.

Morons on Neuroscience

Posted in Politics and Society, Science! on September, 2009 by melendwyr

See this comment over at Scalzi’s site.

This is why I love having a degree in Cognitive Psychology with an emphasis in neurology, because it lets me be fully justified when I point out the stupidity of statements like

There are judgements adults can make that children and even adolescents simply do not have the brain structures to make.

That’s utterly hilarious. The final stages of brain development, initiated at puberty, involve the destruction of connections and the massive pruning of redundancy. Adults have less potential and fewer brain structures than children and early adolescents, which is why they cannot pick up languages easily through casual experience, cannot learn to identify phonemes not present in their native languages, and have a very difficult time adopting or abolishing their existing accents and pronunciations.

There’s a tradeoff involved: greater speed and efficiency for impaired flexibility and potential. If you haven’t developed the capacity to do things once the pruning takes place, generally you never will. The late neural pruning exhibited by human beings is a major factor in our increased intelligence and flexibility compared to the majority of animals – the period in which they can learn and adapt is extremely limited, far more so than our own.

In adolescence, the brain changes from the child form to the adult form essentially from the back forwards: the old brain first, the new brain last. (Call that an example of ontogeny recapitulating phylogeny if you want.) Teenagers develop the ability to do crazy skateboard tricks YEARS before they develop the sense NOT to do them. The part of the brain that successfully predicts the consequences of actions develops only very late in adolescence, in fact one might say that the completion of that development IS the completion of adolescence.

Those ‘final stages of development’ involve the loss of the ability to develop functional systems, not their development. A person who hasn’t developed functional frontal structures by the time the pruning occurs will never do so. It in no way follows that the functional structures have not developed before the pruning – in fact, the existence of adults with effective frontal lobes is the definitive demonstration that such development occurs.

In terms of the legal definitions of child and adult, the distinction is arbitrary, having nothing to do with individual competence. There are lots and lots of adults that lack the competence it’s assumed they have because of their age, and lots and lots of legal minors who are far more competent than the adult average.

Hell, most adults never progress beyond concrete reasoning, even in advanced countries. It’s even worse in more primitive societies.

Cheryl Morgan on Gender

Posted in Politics and Society, Science!, Things You Should Read with tags , , , , , on September, 2009 by melendwyr

See her post on her website, Cheryl’s Mewsings, here.

It’s excellent except for this part:

However, there is a fair amount of evidence that some forms of gendered behavior have a biological component, and that treatment with hormones and similar chemicals, or even neuro-surgery, can cause animals to change their gendered behavior. Presumably the same is possible for humans.

The best available evidence is that it’s not. At least, not in any non-trivial sense – sufficiently advanced neurosurgery could change any behavior, and sufficiently primitive neurosurgery can eliminate any behavior. But that’s not what’s being discussed.

Identity and sexual orientation resist every mode of therapy and attempt to change known. It is possible to destroy cognitive function to the point where unusual concepts of identity and disapproved sexual orientations no longer manifest, certainly. But changing from one to the other? Can’t be done.

The article is definitely worth reading, and clarifies issues many people are confused about to a high degree. With such contentious issues of definition, I’m sure not everyone will agree completely with her usages, but they’re a good starting point for discussion.

[Edit: Clarification] The best available evidence is that orientation and gender identity cannot be changed in humans. I wasn’t trying to suggest that the evidence is against biological components to both those things – quite the opposite.

Principled Stands

Posted in Politics and Society, Science! with tags , , , on September, 2009 by melendwyr

Carl Zimmer has said that he will not participate in any further Blogginghead.tv discussions. So has Sean Carroll.

Good for them.

I should get around to adding them to my list of science-y blogs. I prefer to stay away from Discover, though, given my opinions on how they’ve changed over the past decade or so.

First, Do No Harm (Part 2)

Posted in Doom, GIGO, Medicine, Science! with tags , , , , , on August, 2009 by melendwyr

What does Dr. Vertosick suggest is the cause of such snafus as the EC-IC bypass?

As the EC-IC bypass affair illustrates, experimental operations can jump into the medical mainstream long before anyone establishes their efficacy – or even their safety. Although ego and greed help keep unproved procedures in the operating room, it’s bad scientific judgment that puts them there in the first place.

Before new drugs can be marketed, they undergo three levels of testing. First, volunteers are given the drug to see how toxic it is and how well it’s absorbed and tolerated by the body. (This leads to specifically unexpected yet globally inevitable tragedies every once in a while, most particularly when one of the test subjects happens to be in a minority that has serious reactions to a drug that hadn’t been previously observed.) Then, once the obvious risks of the drug are known, it’s given to ill patients to see if they do better on it than previous, retrospective patients. Finally randomized trials are conducted to compare treated and untreated patients directly. Only when this last stage has been successfully completed is a drug considered for approval.

There is no such regulation on surgical procedures; although the FDA regulates surgical devices, it has no jurisdiction over surgeries. There is no legal obligation for surgeons to test therapies with the third stage of randomized trials. And since they can charge for any surgery, surgeons have no financial reason to put their therapies through expensive and difficult examination.

It is not unusual for surgical procedures to be widely implemented without rigorous testing – it is in fact quite standard. Vertosick offers the example of spinal fusion to treat back pain caused by degenerating disks. The disks can be removed “in a simple, two-hour operation”, or surgeons can remove the disk and implant a steel plate, which in theory helps to stabilize the spine, a procedure which is more involved and incidentally costs two to three times more. As Vertosick points out, “there’s no evidence that it’s any more effective than the simpler procedure”.

The reasons why so little testing is done are legion. It takes lots of money and effort to conduct randomized trials, patients don’t want to be assigned to “nonsurgical” groups – they want to be ‘treated’ when they go to surgeons, and that usually means undergoing surgery – and they go elsewhere for the surgery if they can’t get it in the study. Many doctors are not qualified to evaluate the statistical results produced, and often don’t believe the results when they arrive. Some of the critics of the NINCDS study initially complained that the best candidates for the surgery left and had the surgery elsewhere when they had been assigned to nontreatment, for example. But doctors often simply ignore studies, even when there aren’t potential confounding issues like that one, simply because they want to stick with what they “know” works.

What is known now is that the retrospective studies used by Yasargil did not accurately reflect the rates of stroke at that time. Too little was understood about how people’s health had changed between the time those studies were done and the time EC-IC was first being tested, and our assumptions that the two were comparable turned out to be wrong. As a result, Yasargil reached the wrong conclusion.

He didn’t even do something wrong – or at least, wronger than usual in medicine. He was in fact more careful than most such innovators, and certain more so than those who adopted his ideas without subjecting them to any testing at all. He was merely tragically wrong.

Other, equally tragic mistakes happen not through bad luck, but through incompetence, willful ignorance, and arrogance.