It takes brains to understand an IQ's value

Published on Saturday 19 August 2006 00:53

WHAT is intelligence? Is it a mind-boggling capacity for general knowledge, or the ability to solve novel problems? Perhaps it is original thought, the ability to formulate witty remarks or learn multiple languages.

Although all these criteria can be used to describe intelligence to some degree, it is a quality that is impossible to summarise in one sentence, let alone put a number on. So is it appropriate to rank individuals on a numerical sliding scale which tells them their "intelligence quotient", or IQ?

Historically, teachers have used IQ tests to measure a child's ability and potential. In 1905, the French psychologist Alfred Binet developed the Binet-Simon test to identify underachieving schoolchildren.

The concept of "mental age", as distinguished from "chronological age", was introduced in 1911.

The Binet-Simon test was revised into the Stanford-Binet, which now forms the basis of present IQ tests used by teachers and employers.

According to one study, the average Scot's IQ score of 97 is well below the England and Wales average of 100.5, particularly London and the south-east of England which tops the UK with an average score of 102. This picture was blamed on the constant brain drain of intelligent Scots moving south or overseas.

But should we be worried? For many leading scientists, IQ is not actually the smartest way to assess intelligence.

"If you are interested in how creative someone is, or how they can link together unusual ideas, then IQ tests are not so useful," says Baroness Susan Greenfield, a professor of pharmacology at Oxford University and a director of the Royal Institution of Great Britain.

And Professor Colin Blakemore, the chief executive of the Medical Research Council and a leading neuroscientist, says: "Conventional IQ tests are not full measures of the brightness of an individual."

Even a spokesperson from Mensa, the society whose requirement for membership is that an individual's IQ falls within the top 2 per cent of the population, admits: "IQ tests can only measure a narrow field of intelligence ... that which they are designed to measure."

The problem with defining intelligence is that it is inextricably linked to culture and educational background.

"Every IQ test is immediately loaded against some people, and therefore psychologists are generally wary of the idea," warns Dr Colin Gill, of the British Psychological Society.

Someone with a good educational background will always have a significant advantage in IQ tests over someone who has never attended school, even if they are more intelligent.

Similarly, different cultures value specific types of intelligence. The number-crunching prowess of a high-flying City banker could not be further from the ability of a tribesman to hunt successfully and feed his family. However, both these individuals use different abilities that are considered 'intelligent' in their own cultures.

So can we still hail University Challenge and other quiz-show champions with the title of Brain of Britain?

In Dr Gill's view: "Anyone can learn things, but intelligence is how you apply it." A five-year-old who can recite Shakespeare is not necessarily super-intelligent, as they may not understand the prose."

Environmental factors, from parental input to environmental toxins, can have long-lasting effects on the brain, including intelligence.

In the last decade, learning a musical instrument and listening to classical music have been linked to enhanced IQ.

Keeping the mind active by constant challenges, such as doing crosswords or sudoku, is said to prevent or delay the onset of mental decline and illnesses such as Alzheimer's.

It is thought that all of these activities strengthen the connections between different parts of the brain to enable it to work efficiently. However, the precise way in which nurture affects brain-power remains a mystery.

So what is our current understanding? It is clear that both nature and nurture contribute to intelligence and that IQ tests have their limitations and should be interpreted cautiously in the context of culture and educational background. There are also many different types of intelligences and each of us "shines" in particular ways.

"The mind is like a Swiss Army penknife and although you might not have specific strengths in one area, you could have fantastic strengths in another," says Dr Gill.

And finally, there is a glimmer of hope for those of us who worry that we are not the brightest kids on the block.

Psychological evidence strongly indicates that motivation plays a key role in developing expertise in any field, from chess-playing to music.

Experts are made, not born.

Mensa mini quiz

• 1. Rearrange the letters of the name SOCRATES to give two other words. All eight letters must be used in both words. What are they?

• 2. What number should appear next in this sequence: 2 6 14 30 62 126 ?

• 3. What four-letter word can be attached to the end of the words BUSY and EVERY and to the beginning of the words WORK and GUARD to create four new longer words?

• 4. A pet shop has 8 hamsters, 18 rabbits and 7 guinea pigs. How many dogs does it have?

• 5. Rearrange each of the following words to form a name. What are the four names? MAIDEN AURAL SAIL LONE

• 6. I am a large animal. Change one letter and I am a dwelling. Change another letter and I am a very small animal. Remove one letter and I am a river. Finally change one letter and I am an electrical device. What was I and what did I become?

Answers:

1. Coarsest and coasters.

2. 254. (Add 1, then multiply by 2 to get next number).

3. Body (busybody, everybody, bodywork, bodyguard).

4. Four: The alphabetical position of the initial letter gives the amount.

5. Damien, Laura, Lisa and Noel (or Leon)

6. Horse, house, mouse, Ouse and fuse