Although the WAIS is the most widely used intelligence test, its perspective, that an overall IQ score is a meaningful description of a person’s intelligence, has been challenged. Critics argue that giving people an overall IQ score conveys the impression that there is only one kind of intelligence. The fact that brain damage may diminish one ability but not others suggests that at least some mental abilities may exist independently (not related to general intelligence).

Further evidence for this idea comes from savant syndrome, a condition in which a person of very limited overall intelligence has a single ability that is truly exceptional, such as an amazing memory for music, numbers, or spatial relationships. A single IQ score would not capture the savant’s unusual profile of abilities.