There is no denying it: Boys think differently from girls. Even though recent brain research evidence is controversial(争议的), that conclusion seems inescapable. One clue to brain differences between the sexes came from observation of infants. One study found that from shortly after birth, females are more sensitive to certain types of sounds, particularly to a mother's voice. Female babies are also more easily awoken by loud noises. Tests show girls have increased skin sensitivity, particularly in the fingertips, and are better at fine motor performance. Female infants speak sooner, have larger vocabularies and rarely show speech mistakes. (Stuttering, for instance, occurs almost only among boys.) Girls exceed boys in language abilities, and this early linguistic bias(倾向) often continues throughout life. Girls read sooner, learn foreign languages more easily and, as a result, are mole likely to enter to occupations involving language mastery. Boys, in contrast, show an early visual superiority. They are also clumsier, performing poorly at something like arranging a row of beads, but excel at other activities calling on total body coordination. A study of preschool children by psychologist Diane McGuinness of Standford University found boys more curious, especially in regard to exploring his environment. Her studies also confirmed that males are better at manipulating three-dimensional space. There is evidence that some of these differences in performance are differences in brain organization between boys and girls. Overall, verbal and spatial abilities in boys tend to be 'packaged' into different hemisphere: the right hemisphere for nonverbal tasks, the left for verbal tasks. But in girls nonverbal skills are likely to be found on both sides of the brain. The hemispheres of women's brains may be less specialized for these functions. This passage is mainly about that ______.