On egregious nonsense

So. Of all the pseudoscientific nonsense out there (and there’s a LOT), homeopathy bothers me more than any other I can think of offhand. I’m not entirely sure why, but I think it’s because homeopathy lacks even the prima facie sort of plausibility possessed by modalities like acupuncture or chiropractic.

The background for homeopathy has been covered much more expertly elsewhere, so I’ll just give a quick summary. Back in the 1800s, a doctor named Samuel Hahnemann took a bit of quinine (used as treatment for malaria). It’s also poisonous, and when he took it he felt it induced symptoms similar to those of malaria. He decided that things which cure someone who is sick will create the symptoms of that illness in a healthy individual. This is the ‘like cures like’ concept of homeopathy, that by giving substances to healthy persons and noting how they feel, you can use those substances to cure those symptoms in a sick individual.

Note that this isn’t like vaccination – you aren’t acclimatizing their system or provoking an immune response so your body will recognize a virus later. It’s literally supposed to be curative.

There’s another principle. Hahnemann noticed that when he gave substances to his patients (like arsenic, for example) they ended up healthier when the substance was more dilute. This makes some sense – after all, you’ll be much healthier if you consume almost pure water or a sugar pill than if you consume arsenic or quinine (unless in the latter case you have malaria). Thus the second principle – dilution. Homeopathic ‘medicines’ are typically diluted to 20-30C, each C standing for a 1-in-10 dilution. So take 1mL of a 10mL solution, mix it with 9mL of pure water, and repeat 19-29 more times.

Now, a dilution of 10-23 or so will have about one molecule of the original substance in one mole of the solution (so 1 molecule per 16 grams) of water. It gets much less likely that you’ll find a single molecule of the original substance for every ‘to the minus’ that you go. So at 10-30 you’d have to drink oceans and oceans of a homeopathic solution to actually consume a single molecule of whatever substance was originally there.

Thus. We have a medical principle (like cures like) that’s not actually true, and a technical principle (of increasing potency with increasing dilution) that doesn’t actually make sense.

The key part I’ve left out? Succussion. Hahnemann said it would only work if you shook/tapped the substance between dilutions. He recommended a certain number of taps on the cover of a bible, to ‘potentize’ the substance. It won’t work otherwise, you see.

Homeopathy isn’t naturopathy (which I have my own problems with). It isn’t herbalism. It’s nonsensical magic that ought to be transparently useless at first glance.

I’ll leave you with the video below, and if you want more information I suggest the ‘Homeopathy’ category at Science-Based Medicine.

Neuropsychology and racism

This could be an interesting discussion about the huge debate among scientists over questions of IQ, environment, race (in the sense of the social construct rather than any sort of precise ethnic identity), and idiocies like The Bell Curve. There are some very good criticisms to be made regarding IQ as a construct, as well as the idea of an underlying -g- factor for general cognitive performance. If pressed I’ll admit a great deal of sympathy for Neurodiversity though I do take some issue with parts.

With that in mind, I’d like to describe a study in the most recent issue of Current Biology 20(7). In it, Dr. Santos and her colleagues compared attitudes towards race and gender between normal children and children with Williams Syndrome. Normal here, as per usual in the scientific literature, should be taken to mean devoid of any confounding clinical condition, rather than a value judgment.

Anyways. They had 20 normal children matched to 20 WS children, each group having 10 males and 10 females. They found that WS children, who genetically lack social fear of strangers, had similar rates of gender stereotyping, but lacked the negative racial stereotyping found in the normal group. This was done by showing a picture accompanied by a short story which used one of six positive or negative qualifiers. The images were of two figures – either a white and a black girl, white and black boy, a black man and black woman, or a white man and white woman. The children were asked to point to which figure in the image-pair the qualifier applied to – responses were compared to 50%, where the qualifier would be applied to either figure at chance rates.

This suggests that social fear of strangers as engendered by some of the missing genes of WS plays a strong role in developing negative racial attitudes, but that negative gender attitudes develop through some other mechanism. The authors suggest social imitative learning and overgeneralization as potential roots (given previous studies they’ve conducted).

There is a neural basis for all of this. In humans the amygdala is known to be involved in fear/emotional responses and learning. Children with WS have abnormal regulation of the amygdala by the prefrontal cortex (involved in executive functions like behavioural initiation and inhibition) and decreased interaction between the amygdala and fusiform face area. This suggest two factors at work, in which children with WS do not recognize out-group faces as out-group, and there is no fear response evoked in the amygdala.

Now, we shouldn’t immediately go out and delete a chunk of our chromosome 7. People with WS have a host of problems that accompany any chromosomal disorder. Still, studies like this are useful for teasing out some of the biological bases of social attitudes, as well as making monistic naturalists like me pretty happy. They also show how people with natural differences can be helpful in research not strictly connected to their difference. Rather than lesioning a bunch of people along the amygdala and FFA we can find a group of people with very well-defined differences in neural development of structure who have a particular phenotype. Comparing them to ‘normal’, otherwise matched individuals can lead to very fruitful results we could not otherwise discover. Obviously, such research needs to be carried out in participation with the individuals involved, rather than studying them as freaks or weird abnormalities. But if you can do that then you can find out some pretty nifty things.

Santos A, Meyer-Lindenberg A, Deruelle C. Absence of racial, but not gender, stereotyping in Williams syndrome children. Current Biology 20(7):R307-R308.

Science and romance

This song is great; it does a good job of pointing out the foolishness that is the whole “one twoo wuv” thing while not downplaying how important our relationships with SOs can be. This is a good example of positive atheism. While there are some pokes taken at annoying tropes and the style of the song is clearly a parody of insipid pop songs proclaiming undying singular love, the song still comes across as deeply romantic.

Admittedly, I do think ‘You’re not special – I mean, you’re special but you fall within a bell curve’ to be a great line, so I might be falling into one tail of an entirely different bell curve.

TMS and Moral Judgements

As it’s been pointed out that I’m not exactly Orac I suppose I can post some shorter things. I’ve been neglecting this blog for the past month or so – apparently this graduate school thing is pretty hard.

So, on to the nifty stuff. A recent article in PNAS describes a study which used transcranial magnetic stimulation (TMS) to bias people’s moral choices during a theory of mind scenario, which is pretty cool.

TMS is a technique that sounds a bit sketchy at first but is becoming well established. Magnetic stuff is pretty prone to quackery but in this case there is solid science to back up using magnetic coils to stimulate or flatten neural activity directly below the coil. This is pretty awesome because cognitive and other neuroscientific studies of the brain tend to be very correlational, and do not usually establish causation. With TMS, you can directly affect firing in the brain without any sort of invasive technique, almost (but not quite) as though you can create temporary lesions. This direct manipulation allows you to establish more robustly causal effects.

Essentially, the study was interested to see if TMS suppression of the right temporoparietal junction (RTJ), a brain region involved in Theory of Mind, would change participants’ attitudes to a moral situation. Theory of Mind involves how we attribute mental states and beliefs to others – how we escape solipsism, essentially. Participants were asked to rate how morally blameworthy Grace was in the situations below – a total of 48 such scenarios were examined.

Now, while I take strong issue with some of their statistics (remember my bit about multiple comparisons? They made that mistake) their results are intriguing. What they found was that in situations where the subject had intended harm but failed to cause it (ie lower-left), TMS-induced depression of the RTJ caused participants to view this action as less morally blameworthy than when they received no TMS or TMS to a slightly different region.

What does this mean? Essentially, it shows a section of the brain influences how we judge the actions of others based on their motives and the outcomes of their actions. Perhaps if the region is excited, people would perceive certain belief/outcome combinations as more morally blameworthy, or perhaps the RTJ influence only the negative/neutral belief/outcome pair, and other regions are involved in processing different situations.

Either way it demonstrates a neural basis for human moral judgements, something I’m quite pleased to see. And if anyone’s interested, I can send them some more info on the study.