Mental age

Mental age is a concept related to intelligence. It looks at how a specific child, at a specific age—usually today, now—performs intellectually, compared to average intellectual performance for that physical age, measured in years. The physical age of the child is compared to the intellectual performance of the child, based on performance in tests and live assessments by a psychologist. Scores achieved by the child in question are compared to scores in the middle of a bell curve for children of the same age

However, mental age varies according to what kind of intelligence is measured. A child's intellectual age can be average for his physical age but the same child's emotional intelligence can be immature for his physical age. In this psychologists often remark girls are more emotionally mature than boys in the tween years. Also a six-year-old child intellectually gifted in Piaget terms, can remain a three-year-old child in terms of emotional maturity. Mental age was once considered a controversial concept.

During much of the nineteenth century, theories of intelligence focused on measuring the size of human skulls. Anthropologist well known for their attempts in correlating cranial size and capacity with intellectual potential are Samuel Morton and Paul Broca.

The modern theories of intelligence began to emerge along with experimental psychology. This is when much of psychology was moving from philosophical to more biology and medical science basis. In 1890, James Cattell published what some consider the first "mental test". Cattell was more focused on heredity rather than environment. This spurs much of the debate about the nature of intelligence.

Mental age was first defined by the French psychologist Alfred Binet, who introduced the intelligence test in 1905, with the assistance of Theodore Simon. Binet's experiments on French schoolchildren laid the framework for future experiments into the mind throughout the Twentieth Century. He created an experiment that was designed as a test to be completed quickly and was taken by various ages of children. As was expected, the older children performed better on these tests. However, the younger children who had exceeded the average of their peers were said to have a higher "mental age" and those who performed below average were deemed to have a lower mental age. Binet's theories suggested that while mental age was a useful indicator, it was by no means permanently affixed and individual growth or decline could be attributed to changes in teaching methods and experiences.

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