Saturday, September 15, 2007

Twists and twirls of an individual mind

15 Sep 2007, ST

By David Brooks

A NICE phenomenon of the past few years is the diminishing influence of IQ. For a time, IQ was the most reliable method we had to capture mental aptitude.

People had the impression that we are all born with these clever little information-processing engines in our heads, and that smart people have a lot more horsepower than dumb people.

And in fact, there is something to that. There is such a thing as general intelligence; people who are good at one mental skill tend to be good at others. This intelligence is partly hereditary.

An analysis by Mr Bernie Devlin of the University of Pittsburgh finds that genes account for about 48 per cent of the differences in IQ scores. And there is evidence that people with bigger brains tend to have higher intelligence.

But there has always been something opaque about IQ. There is no consensus about what intelligence is. Some people think it is the ability to adapt to an environment, others that capacity to think abstractly, and so on.

Then there are weird patterns. For example, over the past century, average IQ scores have risen at a rate of about three to six points per decade. This phenomenon, known as the Flynn Effect, has been measured in many countries and across all age groups. Nobody seems to understand why this happens, or why it seems to be petering out in some places, like Scandinavia.

IQ can be powerfully affected by the environment. As Mr Eric Turkheimer of the University of Virginia and others have shown, growing up in poverty can affect your intelligence for the worse.

Growing up in an emotionally strangled household also affects IQ. One of the classic findings of this was made by H.M. Skeels in the 1930s. He studied mentally-retarded orphans who were put in foster homes. After four years, their IQs diverged by an amazing 50 points from orphans who were not moved.

And the remarkable thing is, the mothers who adopted the orphans were also mentally retarded and living in different institutions. It was not tutoring that produced the IQ spike; it was love.

Then, finally, there are the various theories of multiple intelligence. We do not just have one thing called intelligence. We have a lot of distinct mental capacities. These theories thrive, despite resistance from the statisticians, because they explain everyday experience. I am decent at processing words, but when it comes to calculating the caroms on a pool table, I have the aptitude of a sea slug.

IQ, in other words, is a black box. It measures something, but it is not clear what it is, or whether it is good at predicting how people will do in life. Over the past few years, scientists have opened the black box to investigate the brain itself, not a statistical artefact.

There are now books on mental capacities where IQ and intelligence barely crop up. They are concerned instead with, say, the parallel processes that compete for attention in the brain, and how they integrate. The authors are finding that neural connections are shaped by emotion.

The University of Southern California had a patient rendered emotionless by damage to his frontal lobes. When asked what day he could come back for an appointment, he stood there for nearly half an hour describing the pros and cons of different dates, but was incapable of making a decision. This is not the Spock-like brain engine suggested by the IQ.

Today, the research that dominates public conversation is not about raw brain power but about the strengths and consequences of specific processes.

The cultural consequence is that judging intelligence is less like measuring horsepower in an engine and more like watching ballet. Speed and strength are part of intelligence, and these things can be measured numerically, but the essence of the activity is found in the rhythm and grace and personality - traits that are the products of an idiosyncratic blend of emotions, experiences, motivations and inheritances.

Recent brain research, rather than reducing everything to electrical impulses and quantifiable pulses, actually enhances our appreciation of human complexity and richness.

While psychometrics offered the false allure of objective fact, the new science brings us back into contact with literature, history, the humanities and, ultimately, to the uniqueness of the individual.


No comments: