IQ (Intelligence quotient) is a measure of intelligence calculated by means of intelligence tests. The person's perceived mental age is divided by their real age and multiplied by 100 to give their IQ. Over 80% of people have an IQ of between 80 and 120. Only the top 2% have an IQ of over 130.
IQ tests were originally intended to identify and assess children with special needs. Nowadays the most recognised use for IQ tests is for entry into high IQ societies such as Mensa.
It is often argued that you are born with a certain IQ which is genetically predetermined and there is very little you can do to increase your IQ by any significant amount.
The University of Edinburgh carried out a recent study on over 5,000 into whether or not a mother's breast milk has any influence on a child's intelligence. Perhaps unsurprisingly, a mother's breast milk was found to little or no influence on a child's IQ.
However, other studies in the past have proven that genetics is not the only influencing factor on intelligence.
A study referred to as The Milwaukee Project was carried out in the late 1960s by the University of Wisconsin . The subjects were 40 newborn babies in a deprived area of Milwaukee and all of the subjects' mothers had an IQ of less than 80. Half of the babies received a special education and “home based enrichment” for the first 6 years of their lives while the other half who were the control group received no such advantages.
At the age of 6 the average IQ of the children in the experiment was 120.7 while the average IQ of the children in the control group was just 87.2.
Another experiment carried out in the US was at Glenwood State School . The experiment involved 25 children in a deprived and overcrowded orphanage. Thirteen children were taken away to Glenwood State School to be placed with substitute mothers who cared for them and gave them intellectual stimulation. These children had an average IQ of just 64. For the purposes of the study, the other twelve children were the control group and had an average IQ of 87.
Four years later, 11 out of the 13 children at Glenwood had been adopted and now had an average IQ of 101 which is slightly above average while the children who had been left behind in the orphanage had experienced a dramatic decrease in their IQ to an average of just 66 which is in the bottom 2% of the population.
The general consensus is that IQ is 50% heritable and 50% dependent on environment and as proven by the Glenwood State School experiment the quality of a children's environment can make the difference between being in the bottom 2% and the top 50%.
