Electric brain stimulation decreases IQ scores and racial prejudice

http://www.kurzweilai.net/electric-brain-stimulation-decreases-iq-scores-and-racial-prejudice

by Expeditus419 • 11 years ago

28 28 11 years ago

blueflow3• 11 years ago

... Participants (n=60) were randomly...

Beside from that, the title suggests something like a causal connection when they just found it correlating on a sample of 60 persons? Seriously?

This study is utter bullshit.

joeyo• 11 years ago

Perhaps the sample size isn't as large as you'd prefer, but the use of causal language is appropriate here. Indeed, the authors applied a causal intervention (tDCS or a sham treatment) to randomly assigned subjects. This type of study design is pretty much the classical way to infer a causal relationship.

omginternets5• 11 years ago

Did you read the paper? I don't see how you could walk away with the impression that this is "just correlation", let alone bullshit. Moreover, your quip about n=60 strikes me as the kind of comment made by people who don't know how research and statistics work.

n=60 is actually pretty big for this kind of study (most cognitive studies involving fMRI, for instance, hover around n=20). Either way, simply looking at the sample size is deceiving, as statistical power is what matters in the end. If sufficient power can be achieved with 60 persons, then yours is not a valid criticism.

Concerning the design, this is a straight-up experimental manipulation and not just a correlative study. There were two groups, one which received real tDCS and the other which received a sham tDCS. Subjects were assigned to each group in a double-blind fashion, and the measure of interest here is the improvement between the first test (pre manipulation) and the second test (post manipulation). The use of a sham rules out any placebo/nocebo effects.

This is exactly the kind of study that one would design in order to test causality. We have both temporal precedence and covariance; together, these strongly suggest that tDCS is responsible for the observed effects.

blueflow3• 11 years ago

http://andrewgelman.com/2014/08/04/correlation-even-imply-co...

A correlation in your sample (especially at that size) does not imply a correlation in the population, even if you validate it with additional sham tests.

matt4077• 11 years ago

It's getting really annoying how many self-annoited gods of statistics keep creeping up online.

60 is plenty if the effect is large enough. Hey, even n=4 can make for a good study. Give two of them cyanide and two of them a placebo, let all the trial-size-too-small-correlation-isnt-causation-people watch and then ask them to back up their criticism with a nice helping of the tested substance.

blueflow3• 11 years ago

Exactly,

"... if the effect is large enough"

Klockan• 11 years ago

The same people has no problems accepting n=1 as long as it is an anecdote which purports their world view though.

coldtea• 11 years ago

Who said you need more persons for a study like this?

If the sample is representative (and they don't even claim ot attempt to study something that would only affect a particular group) then 60 are fine, in fact they could do with even less.

Besides, what correlation? This is direct observation, there's no other parameter in play in the test setup.

madaxe_again3• 11 years ago

Wonderful. You just know that some wag will jump on this and twist this into "It is intelligent to be racist!".

Personally, I find the idea of wiring my brain, my self, up to something which zaps it with little to no understanding of the underlying science or function scares the bejesus out of me, and strikes me as a strange at best and stupid at worst thing to do.

Ah, let me just pop a leech on this, it'll get my phlegmatic humour rebalanced.

ams6110• 11 years ago

I agree with the sentiment: electrically tinkering with my brain is not something I would think a good idea, but is it really much different from ingesting various chemicals/pharmaceuticals for essentially the same purpose?

I'm actually not so surprised by the racial prejudice effect. Many low-IQ people I've encountered are execeptionally friendly, accepting, and non-judgemental. Not to say that is evidence of anything, just my experience.

zxcvcxz• 11 years ago

You just know that some wag will jump on this and twist this into "It is intelligent to be racist!".

Not before some wag jumps on it and makes sure anyone who tries to discuss the topic rationally and thoughtfully is already seen as racist and stupid.

I dream of a community where everything is up for discussion, even if I disagree with it.

seivan• 11 years ago

Thank you! I was going to say the same thing.

"Hurry! Before anyone has a simple thought in their head, brand them as racist and misogynist!"

madaxe_again3• 11 years ago

Actually, the first response was from a hellbanned account espousing exactly that point of view.

I'm also not sure where you got that I'm trying to censor discussion - you commented, did you not?

"michas 3 hours ago [dead]

It has nothing to do with intelligence, it is just all about being realist. Existence of different races comes from the fact that there are genetic differences between people. It would be stupid to assume that those genetic differences have no other effect than skin color."

DonHopkins• 11 years ago

I'm sure Eric S Raymond will try to twist this into supporting his racist preconceptions and agenda.

"In the U.S., blacks are 12% of the population but commit 50% of violent crimes; can anyone honestly think this is unconnected to the fact that they average 15 points of IQ lower than the general population? That stupid people are more violent is a fact independent of skin color." -Eric S Raymond

http://esr.ibiblio.org/index.php?p=129

dang• 11 years ago

"Please avoid introducing classic flamewar topics unless you have something genuinely new to say about them."

https://news.ycombinator.com/newsguidelines.html

marcolinux• 11 years ago

Oh the quotes! Same link [1],the next paragraph:

"A black man with an IQ of 85 and a white man with an IQ of 85 are about equally likely to have the character traits of poor impulse control and violent behavior associated with criminality — and both are far more likely to have them than a white or black man with an IQ of 110" -Eric S Raymond

1-http://esr.ibiblio.org/index.php?p=129

golemotron• 11 years ago

I feel a Harrison Bergeron moment coming on.

http://en.wikipedia.org/wiki/Harrison_Bergeron

copsarebastards• 11 years ago

This makes perfect sense based on how tDCS is hypothesized to work.

tDCS is believed to enhance learning by providing more force behind the encoding of memories: it's like pressing harder when writing with a pencil, making it harder to erase. Normally it takes many iterations of practice to encode a complex skill properly, but with more electricity behind the "write" operation it takes fewer iterations.

However, with perceptual reasoning, encoding memories quickly would be counterproductive, because it would cause your first ideas to be firmly encoded, leading you to consider fewer ideas. This would prevent the broader considerations necessary in problem-solving.

I'm not a neuroscientist, so take what I'm saying with a grain of salt. I've just read a lot about tDCS, and have no formal training.

jqm• 11 years ago

If the electrical current were turned up high enough all racial prejudice would disappear and IQ would approach 0.

Electric brain stimulation decreases IQ scores and racial prejudice

Related Stories