Intelligence is the ability to learn from experience, solve problems, and adapt to new situations. Psychologists agree that people have specific abilities, such as verbal and mathematical aptitudes. However, they debate whether a general intelligence (g) factor runs through them all. Factor analysis and studies of special conditions, such as the savant syndrome- a condition in which a person otherwise limited in mental ability has an exceptional specific skill, such as in computation or drawing-have identified clusters of mental aptitudes.
Several studies report a very slight correlation between head size (adjusted for body size) and intelligence test score, and a slightly greater (though still modest) correlation between brain size and intelligence test scores.…