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Electric brain stimulation decreases IQ scores and racial prejudice

kurzweilai.net

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Re: Electric brain stimulation decreases IQ scores and racial prejudice

#11

Post by omginternets »

blueflow wrote: post #7
omginternets wrote: post #6

Earlier quoted context omitted.

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…

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.

Why are we even talking about correlation?

The study performed statistical hypothesis testing to determine that the means of the two groups are probably different.

Edit: and more to your point, correlation of the sample implies correlation of the population if the sample is representative. Is this the case for this particular paper? I don't know and neither does anyone else; that's why replication is the gold standard of scientific validity.

Re: Electric brain stimulation decreases IQ scores and racial prejudice

#12

Post by omginternets »

blueflow wrote: post #10
matt4077 wrote: post #8

Earlier quoted context omitted.

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.

Exactly, "... if the effect is large enough"

Are you saying the effect isn't large enough? If so, why?

Re: Electric brain stimulation decreases IQ scores and racial prejudice

#13

Post by Klockan »

matt4077 wrote: post #8
blueflow wrote: post #3

>... 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.

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.

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

Re: Electric brain stimulation decreases IQ scores and racial prejudice

#14

Post by coldtea »

blueflow wrote: post #3

>... 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.

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.

Re: Electric brain stimulation decreases IQ scores and racial prejudice

#15

Post by zamalek »

blueflow wrote: post #7
omginternets wrote: post #6

Earlier quoted context omitted.

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…

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.

> A correlation in your sample (especially at that size) does not imply a correlation in the population

At least quote the article correctly.

> That is, correlation in the data you happen to have (even if it happens to be “statistically significant”) does not necessarily imply correlation in the population of interest.

(Emphasis mine)

Otherwise you might as well throw out centuries of mathematical, statistical and scientific progress. That laptop of yours? Throw it in the trash as it is the culmination of thousands of sham tests and correlations and is therefore clearly impossible.

Re: Electric brain stimulation decreases IQ scores and racial prejudice

#16

Post by ams6110 »

madaxe_again wrote: post #4

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 p…

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.

Re: Electric brain stimulation decreases IQ scores and racial prejudice

#18

Post by [deleted] »

madaxe_again wrote: post #4

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 p…

[deleted]

Re: Electric brain stimulation decreases IQ scores and racial prejudice

#19

Post by zxcvcxz »

madaxe_again wrote: post #4

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 p…

> 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.

Re: Electric brain stimulation decreases IQ scores and racial prejudice

#20

Post by copsarebastards »

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.

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