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Goodbye, IQ Tests: Brain Imaging Predicts Intelligence Levels
An anonymous reader writes "Research from Washington University in St. Louis has identified variations in brain scans that they believe identify portions of the brain that are responsible for intelligence (abstract). As suspected (and as explained by cartoons) brain size does play a small role; they said that brain size accounts for 6.7 percent of variance in intelligence. Recent research has placed the brain's prefrontal cortex, a region just behind the forehead, as providing for 5 percent of the variation in intelligence between people. The research from Washington University targets the left prefrontal cortex, and the strength of neural connections that it has to the rest of the brain. They think these differences account for 10 percent of differences in intelligence among people. The study is the first to connect those differences to intelligence in people."
The question is, do the excess connections cause intelligence, or does working the brain cause the excess connections?
But what about your Wisdom?
Seems a better measure than how fast you can perform math, patern recognition, etc.
Thanks to AD&D I learned about the importance of balance Int with Wis
A feeling of having made the same mistake before: Deja Foobar
yeah, but now we could quantify how much intelligence a person is wasting.
Seems like a pretty big gap... they're saying they've identified 3 factors that together make up (if they can be believed) about 21.7% of the "variation in intelligence". So where's the other 78.3%?
I'm not criticizing their results. Maybe they are correct. But it still isn't saying a hell of a lot.
The answer to your question is: it depends.
"Intelligence" has two separate and distinct meanings in colloquial English. It can mean the ease and speed of comprehension, or it can mean the total amount of knowledge a person has.
Working the brain will cause it to make more connections, and some of these connections translate in an abstract way to other topics. Thus, a Chemistry major might be able to pick up cooking more easily, or a farmer's son might make a better cartographer.
In some sense, the brain learns "patterns", and there are only so many patterns in the world. For example: once you get a deep understanting of exponential functions, you start to see them in the real world. Compound interest is an exponential function, for example.
Hence, gaining more connections can translate into an increase in faster understanding and comprehension of other things - they are "similar" to other things you've seen.
The other side of the question has to do with learning original patterns. This is based on fundamental processes in the brain and is all balled up with information and complexity theory, as well as motivation and perceived value.
There are at least 2 genes known to confer a general increase in intelligence, so it seems likely that the fundamental processes are more or less efficient depending on the genetic makeup.
There is also abundant evidence that the environment plays an overwhelming role in the brain's development at the current time, and in the current culture. The 2 genes mentioned are predictors of success and intelligence, but there are better predictors based on parental choices (how the child was raised) and random luck (being in the right place at the right time).
So even if you don't happen to have those 2 genes, you can become highly intelligent by working harder.
So back to your question: working the brain causes more connections, and by one mechanism these connections will be perceived as an increase in intelligence. Without exposure to information or variation in environment, there will be fewer connections.
OTOH, there is a genetic component which will cause more connections and a higher intelligence from the same data, all else being equal.
When I went to university, I thought I might find people mostly with similar opinions (politics etc) to myself, being of the same IQ group. Up until then I had always thought most people around me had plainly idiotic opinions and I had put it down to their being a bit low on brainpower. In fact I found the others at uni (who we can assume were all of significantly higher IQ than average) had the same range of idiotic opinions (IMHO) as people generally.
Surveys have shown that the distribution of political, ethical and religious opinions tends to be the same whatever the IQ group. I find this strange.
Take the infamous Mrs Thatcher. I can recognise that she was a very intelligent woman but at the same time stupid in many things. Like she thought that by privatising industries and selling the shares to the public (cheap), the British people would become shareholders in large numbers - a "shareholding democracy" - and we would all then clamour for more efficiency in those industries as shareholders. What happened is that we bought those shares and then promptly sold them again (mostly to foreign enterprises as it turned out - a large part of UK rail freight is now owned by the *nationalised* German Railways!). The point is that most people with any sense could have told her that would happen - why could someone so intelligent not see it herself? Just one example of my point.
People have been trying to measure intelligence for well over a hundred years now, but I have yet to see anybody precisely and fully define exactly what it is they are measuring.
And don't say IQ - the only thing IQ tests measure is the ability to do IQ tests. Read up on their history. There is nothing scientific about their origin.
Never trust a man in a blue trench coat, Never drive a car when you're dead