
Human Intelligence Has Declined Since Victorian Era, Research Suggests - monort
http://www.huffingtonpost.com/2013/05/22/people-getting-dumber-human-intelligence-victoria-era_n_3293846.html
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lutusp
This isn't science, it's sociology and psychology in equal measure. Reaction
time is an innately crude measure, and extrapolating from reaction time to
intelligence is dubious at best. To see my point, imagine using it to measure
Stephen Hawking's intelligence.

I'm a pretty bright person, but I'm almost 70 years old and I just don't have
the reaction times of a young person -- or that I did when I was younger and a
great deal dumber :).

If readers watched me typing at my keyboard, some would likely find it
frustrating and might wonder how anything useful could possibly issue from all
that slow pecking. But the end result is a crude approximation of intelligence
-- created slowly, and in a way that would flunk the kind of examination on
which the linked study relies.

At the very least, the study relies on a superficial correlation between
reaction time and intelligence in young people, while ignoring the fact that
as the years pass one's intelligence might increase, while one's reaction
times decrease.

When I was about 20 I took an IQ test at NYU, one that relied more than
anything else on speed of response. The outcome was that I got the "very
superior" designation I expected and was accustomed to in those days. But on
reflection I realized I had taken so many of those kinds of tests that I was
simply nailing the test, not the property it was meant to measure. If I took
the same test today I would probably not do very well, but I'm certainly
functioning at a higher level than I did then.

Closing remark. When Alfred Binet was asked what IQ was, he replied, "It's
what my test measures."

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IvyMike
> Reaction time reflects a person's mental processing speed, and so is
> considered an indication of general intelligence.

I reject this premise.

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dragonwriter
The premise you (rightly) reject is misreported -- the actual reason reaction
time is being used as a proxy for IQ is that it has been established to have a
correlation with IQ, not for the stupid reason reported in the HuffPo article.
(Its like whoever wrote that article didn't even read the abstract of the
paper its about.)

OTOH, I'm not convinced there is enough of an understanding of that
correlation (particularly an understanding of what other factors contribute to
reaction time variations and how they have varied over the time in question)
to simply assume that it can be treated as invariant in conditions other than
those in which the correlation has been studied.

~~~
lutusp
An argument against the significance of the correlation is that old people's
reaction times decline, while their intelligence may continue to increase.
Consequently a test that measured abilities other than reaction time would
favor that age group over a test series based on reaction time.

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skywhopper
About 10 years ago I was diagnosed with ADHD, and as part of the testing I was
given an IQ test. I don't recall now which test it was, but the scores were
given in four categories, and while in three of the categories my scores were
very closely comparable with each other, the "visual intelligence" score--
which included a computerized reaction time test--was significantly lower.

As I understood their explanation at the time, this sort of discrepancy
between category scores was common among ADHD sufferers, though they could
only speculate as to why.

(My own explanation of this that feels right for me based on my own experience
with ADHD is that some parts of my brain are operating at different speeds
than others, but total appropriate coordination of action requires all the
elements to be in sync. And when these elements are out of sync, they result
in the symptoms that together are recognized as ADHD.)

Point being that I'd be curious to see if the drop-off in reaction times
correlates in any useful way to the rise in ADHD. Perhaps there's a connection
there (even if the reaction time test is pointless and ADHD is just a mass-
delusional means to excuse epidemic amphetamine abuse).

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Palomides
punchline of what they actually studied: "As for Dr. te Nijenhuis and
colleagues, they analyzed the results of 14 intelligence studies conducted
between 1884 to 2004, including one by Sir Francis Galton, an English
anthropologist and a cousin of Charles Darwin. Each study gauged participants'
so-called visual reaction times -- how long it took them to press a button in
response to seeing a stimulus. Reaction time reflects a person's mental
processing speed, and so is considered an indication of general intelligence."

it seems like a big jump from reaction time to intelligence in any more
general sense.

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EGreg
I call bull$5*7 on this article.

Explanation: they measured visual response speed and only briefly mentioned
the Flynn effect with a "maybe" explanation? Not scientific.

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clutterjoe
Idiocracy was still a bad movie.

