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Parasites wreck the brain?
July 1, 2010 2:14 PM   Subscribe

Parasites may affect brain function: Toxoplasmosis is a famous example. Now researchers have proposed that country-by-country differences in IQ can be explained, in part, by parasite burden.
posted by jjray (44 comments total) 12 users marked this as a favorite

 
AI WUB KITTIES.
posted by Artw at 2:15 PM on July 1, 2010 [11 favorites]


BTW, I can see some ways in which this article might be a little controversial.
posted by Artw at 2:16 PM on July 1, 2010 [2 favorites]


That's just the parasites talking.
posted by Bromius at 2:17 PM on July 1, 2010 [4 favorites]


Metafilter and 4chan are a paraistes that wrecked my brian i tell u whut
posted by everichon at 2:19 PM on July 1, 2010 [6 favorites]


The thing with this is...I mean, what I'm getting from this is...uh...hang on, got to go feed the cats.
posted by infinitywaltz at 2:21 PM on July 1, 2010


boing boing on this. Risk taking, etc.
posted by fixedgear at 2:23 PM on July 1, 2010


Funny how IQ always seems to track with socio-economic conditions. It's like the two are related.
posted by Panjandrum at 2:23 PM on July 1, 2010 [25 favorites]


Pfft. Nonsense. As you can see, this researcher has the low, sloping brow of a congenital moron. And that's moron in the clinical sense.
posted by electroboy at 2:24 PM on July 1, 2010


What isn't explained is that the IQ differences can also be explained, in part, by the availability of Crunch Berries.
posted by rhizome at 2:25 PM on July 1, 2010 [7 favorites]


Apparently these two guys have tried to explain nearly everything with parasites. See the bottom paragraph on Discover's blog post on the topic.
posted by GuyZero at 2:29 PM on July 1, 2010 [3 favorites]


The real problem here is that the researchers were all born while Mercury was in conjunction with Saturn.
posted by shakespeherian at 2:30 PM on July 1, 2010 [2 favorites]


And on the flipside, very low parasite load in Western countries is thought to be correlated with high prevalence of all sorts of autoimmune diseases.

My favorite specific example of this is the theory that GI autoimmune diseases like Crohn's and ulcerative colitis develop because kids aren't walking around with the enormous intestinal "worm burdens" that were present over the vast majority of human evolutionary history.
posted by killdevil at 2:30 PM on July 1, 2010 [1 favorite]


Thing is that disease load explains economic underdevelopment and bad government through exogenous mechanisms. See this very famous paper, which is excellent and you're bad if you don't like it. And those factors will tend to depress measured IQ.
posted by grobstein at 2:31 PM on July 1, 2010 [1 favorite]


Indeed, what better and more reliable indicator to use than IQ. Also, I thought IQ 100 was supposed to be the average value in a population. Or median. Or whatever. I'm not from China, I wouldn't know.
posted by Laotic at 2:32 PM on July 1, 2010


Newsflash: lack of sewers and clean water supply makes life really shitty in lots of ways.
posted by Rhomboid at 2:32 PM on July 1, 2010 [4 favorites]


See the bottom paragraph on Discover's blog post on the topic.

Excellent analysis. Correlation ≠ Causation.
posted by zarq at 2:35 PM on July 1, 2010


"I was born here! I raised a cloud of children here! My ancestors came here on the sandwich!"
posted by bicyclefish at 2:36 PM on July 1, 2010 [2 favorites]


Funny how IQ always seems to track with socio-economic conditions. It's like the two are related.

The argument is of course why they are related. Add this to list of theories.
posted by longsleeves at 2:37 PM on July 1, 2010 [1 favorite]


Oh, where to begin about my love of how some parasites alter behavior of their hosts by altering brain function. I'll have to post a few examples on here later. One thing to point out is that while Toxoplasmosis certainly alters behavior in rats, the proof showing it alters human behavior is pretty thin. It can certainly make some people sick in some situations, and it is possible that the mental illness/behavior modification theories are correct, but the jury is far from out on that subject.

In the meantime, no parasite post is complete without a mention of Carl Zimmer's Parasite Blog. He's the author of the highly accessible and quite engrossing Parasite Rex.

As a side hobby, Carl also posts photos that science geeks send to him of their tattoos for his Science Tattoo Emporium (warning: potential thread derail warning due to sheer awesomeness of these tattoos).
posted by SeanOfTheHillPeople at 2:38 PM on July 1, 2010 [2 favorites]


Oh yeah, about China, here's where the data in that map comes from (according to wikipedia):

For People's Republic of China, the authors used a figure of 109.4 for Shanghai and adjusted it down by an arbitrary 6 points because they believed the average across China's rural areas was probably less than that in Shanghai. Another figure from a study done in Beijing was not adjusted downwards. Those two studies formed the resultant score for China (PRC). For the figure of Macau, the average IQ is 104 which is obtained from the score of the Programme for International Student Assessment (PISA) and in such a way transformed into an IQ score.

Caution! Rigorous methodology at work!
posted by Panjandrum at 2:39 PM on July 1, 2010 [7 favorites]


Apparently these two guys have tried to explain nearly everything with parasites.

That's hilarious. The questionable use of the method for measuring IQ (especially "...estimated IQ for another 104 countries by averaging the IQs of nearby nations") is suspect as well.
posted by jjray at 2:39 PM on July 1, 2010


Follow up to the Science Tattoo Emporium... There's a better way of browsing the emporium here.
posted by SeanOfTheHillPeople at 2:40 PM on July 1, 2010


Plague Time by Paul Ewald is also a fun read on this topic.
posted by adamdschneider at 2:50 PM on July 1, 2010


It seems that the relevance of the IQ as a measure of general human capacity is far from certain, so what's the point of scholarship predicated on its centrality as a metric?
posted by clockzero at 2:50 PM on July 1, 2010


So for those too lazy to click, here are the other things the two authors have tried to explain using parasites:
posted by GuyZero at 2:52 PM on July 1, 2010


Whoops. Last two sentences shouldn't have been part of the last bullet there.
posted by GuyZero at 2:53 PM on July 1, 2010


Do Parasites Make You Dumber?

Heck, just one might be all it takes.
posted by hal9k at 2:59 PM on July 1, 2010


Obligatory link to Radiolab episode "Parasites."

I'm kind of surprised we even still use IQ as a measurement of anything useful, considering how unreliable it is. What would Stephen Jay Gould say?
posted by ErikaB at 3:05 PM on July 1, 2010


So these guys are using parasites as their MacGuffin so that they themselves can become parasites on the research and publishing scene. Pick a topic, shop it around. I don't doubt that people can float around like this forever, never getting blackballed. I'm sure useless research can be done rigorously.
posted by rhizome at 3:06 PM on July 1, 2010


If it's going to be a choice between Toxo and Kittens...well, the parasites have already made the decision for me. Sorry folks.
posted by The Lurkers Support Me in Email at 3:19 PM on July 1, 2010


ErikaB: "I'm kind of surprised we even still use IQ as a measurement of anything useful, considering how unreliable it is. What would Stephen Jay Gould say?"

He would probably say we should measure cranial capacity with wheat or something like that.
posted by Barry B. Palindromer at 3:32 PM on July 1, 2010


Recent study shows that researchers use correlation between two variables to trick public into thinking one of them is real when it's not.
posted by r_nebblesworthII at 4:32 PM on July 1, 2010


On that note, mefi's own TLP has done a series of posts recently addressing studies just like this.
posted by r_nebblesworthII at 4:33 PM on July 1, 2010 [1 favorite]


Funny how IQ always seems to track with socio-economic conditions. It's like the two are related.

Sure, no one's disagreeing with that. But as pointed out above, the question is the direction of correlation.
Is it, as proposed here,
parasite burden > IQ > socio-economic success?
or is it
(factor x) > socio-economic success > IQ?
If so, what is factor x?
posted by mdn at 4:40 PM on July 1, 2010


It's parasite burden > socioeconomic success. "IQ" is a mirage, it's just a descriptive bin, inside of it are the various attributes (sanitation, healthy food, medicine, random luck of being born in a prosperous country, education, etc. etc.) that go along with being born in a relatively modern, first-world country.

If so, what is factor x?

Dumb luck, most likely.
posted by r_nebblesworthII at 4:48 PM on July 1, 2010


99% of it is Multiple Man.
posted by Artw at 4:50 PM on July 1, 2010


My favorite specific example of this is the theory that GI autoimmune diseases like Crohn's and ulcerative colitis develop because kids aren't walking around with the enormous intestinal "worm burdens" that were present over the vast majority of human evolutionary history.

Yup. I would not be surprised if the cheapest, easiest, safest, and most effective treatment for a number of autoimmune disorders would turn out to be intentional infection with hookworm. I've heard of a few researchers who actually tried it (in one case because he himself was suffering from an autoimmune disease) with fairly positive results. But I wouldn't want to be the guy asking for money to intentionally infect sick kids with intestinal parasites.
posted by Justinian at 4:53 PM on July 1, 2010


So, these researchers are being controlled by some of the most narcissistic parasites known to humankind? I bet all the other parasites wish they'd shut the hell up already.
posted by orme at 5:15 PM on July 1, 2010


"I was born here! I raised a cloud of children here! My ancestors came here on the sandwich!"

I would totally eat that sandwich.
posted by Pope Guilty at 5:45 PM on July 1, 2010


These guys almost certainly have their causation reversed. It's not a case of parasite burden affecting socio-economic success, but rather socio-economic status determining one's parasite burden.
posted by happyroach at 10:41 PM on July 1, 2010


These guys almost certainly have their causation reversed. It's not a case of parasite burden affecting socio-economic success, but rather socio-economic status determining one's parasite burden.

Joking right? While there are effects in both directions, these distributions mostly match historical as well as contemporary disease burdens, back a couple centuries anyway.
posted by grobstein at 11:29 PM on July 1, 2010


Yes, Republicans have a lot to answer for, but we can't blame everything on them.
posted by Jimmy Havok at 2:31 AM on July 2, 2010


WORMS IN MY BRAIN GET THEM OUT
posted by Joe Chip at 2:41 AM on July 2, 2010


I would totally eat that sandwich.

Your lead pipe wouldn't hurt anymore.
posted by griphus at 7:26 AM on July 2, 2010


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