IQ stands for Intelligence Quotient (N 5). The name, IQ, derives from the history of IQ testing.
Originally, IQ tests were developed for school children and were designed to determine a child's mental age. His mental age was then divided by his chronological age, which gave a quotient, his "intelligence" quotient.
As in percentages, this IQ quotient was then multiplied by 100 to avoid having to deal with decimal points. Thus, if a ten year old tested at a mental age of 10, his IQ was 100, at a mental age of 12, his IQ was 120, at 8, his IQ was 80, and so on.
IQ is no longer a quotient. Instead, it's just a score. (B 34) IQ tests are developed on the basis of the assumption that whatever they're measuring is normally distributed and are…show more content… Anything above or below the normal range is considered abnormal, either abnormally gifted or abnormally deficient. (N 5)
An interesting aspect of keeping mean IQ at an arbitrary value of 100 is that, as the years pass, it's necessary to make IQ tests more and more difficult (N 44). The almost inevitable conclusion is that IQ testing is measuring something that can be learned.
As far as what we call intelligence itself is concerned, there seems to be two types.
One type is called fluid intelligence. It has to do with solving novel, abstract problems, ones to which your accumulation of real-world information has little to contribute. A simple example would be, given a series of numbers, determine what the next number in the series is.
Fluid intelligence involves the use of what are called the "executive functions" of the prefrontal cortex, which include (N 7):
1. Working memory: Solving abstract problems usually involves taking a series of steps, and working memory is the ability to maintain in your mind information developed in previous steps while you concentrate on the next step in developing other information relevant to the solution to the