Interest in intelligence has been longstanding, but it was not until the early 1900’s that intelligence was first quantified with testing. Intelligence testing was first used as a means to identify students who might need educational assistance. Most current intelligence or IQ (intelligence quotient) testing is based on the assumption that intelligence involves multiple different mental abilities. There are several tests commonly used today that tap different mental abilities (e.g. verbal reasoning, nonverbal fluid reasoning, visual-spatial reasoning, working memory, processing speed, etc.) and then yield an overall or Full Scale IQ. An individual’s performance in these different areas of cognitive ability is assessed compared to other individuals of his or her same age.
In general, the higher the IQ score, the faster one’s rate of learning, or the greater one’s learning potential. An IQ score in the range of 90-110 on the Wechsler Intelligence Scale for Children, Fifth Edition, a commonly used IQ test, is considered average. IQ scores in the top 2.5% of those tested, which would be at least two standard deviations above the mean, are considered to be in the intellectually gifted range. Individuals who have IQ scores at or above 130 fall into this category. Although different school districts use different cutoffs to determine who is eligible for gifted/talented education programs, IQ scores actually represent a continuum of ability rather than hard and fast cutoff lines. Indeed, intelligence tests have a standard error of measurement which describes the range inside which an individual’s future scores are expected to fall based on the current score. Consequently, scores may vary slightly when IQ tests are repeated over time.
Does a high IQ translate into academic success? Not necessarily. Although individuals with higher IQ scores typically learn easily, academic success involves many factors including opportunity and motivation. Also, like most people across the intelligence spectrum, individuals who test in the gifted range have personal strengths and weaknesses. Some individuals also have specific learning disabilities that are barriers to learning. Thus, it is important to keep in mind that while an IQ score can provide valuable information about an individual’s cognitive ability, the score by itself does not represent the person.