INTELLIGENCE
Still more evidence that
there really is such a thing as
intelligence comes from the
fact that people’s performance
on tests of their mental skill
and reaction times remains
consistent over time, is partly
inherited from their parents,
and successfully predicts
outcomes such as school
achievements, career success
and even longevity.
Recent research has started
to explore the neural corre-
lates of intelligence. A 2009
study used a brain-scanning
technique, known as diffu-
sion tensor imaging, to
illuminate the efficiency of
neural pathways in the brains
of 92 identical and non-iden-
tical twins. Participants who
scored higher on an intelli-
gence test also tended to have
quicker, more efficient neural
pathways. At the time the results were released, the project leader Paul
Thompson at the University of California put it this way: “When you
say someone is quick-thinking, it’s generally true – the impulses are
going faster and they’re just much more efficient at processing infor-
mation and then making a decision based on it.”
Thompson’s study focused on white-matter tracts in the brain, which
are insulated with fatty material to speed nerve conductance. Other
research shows that intelligence is also linked to quantities of grey matter
(the cell bodies) in different brain regions. In 2007 Rex Jung and Richard
Haier analysed the results from 37 brain-imaging studies and came to
the conclusion that intelligence is associated with grey-matter volume
in fourteen key areas spread throughout the frontal and parietal cortices.
Jung and Haier called this the P-FIT network (as in “parieto-frontal inte-
gration theory”) and they speculated that one day, by focusing on these
areas, brain scans will be able to identify a person’s intelligence profile.
As if formulating the Theory of Relativity
wasn’t enough, Albert Einstein was also a
gifted amateur violinist.