 Additionally, there is some dispute about whether the claimed sex differences in behavior are real. As examples, Grossi and Fine challenge the claim that mental spatial rotation skills are superior for males. Recent evidence suggests that when girls and women practice spatial rotation, say through video games, the differences in performance rapidly disappear (Feng, Spence, and Pratt 2007). Similar arguments can also be made about empathizers. Sex differences in language proficiency tend to disappear as children grow older. There are also reasons to doubt the accuracy of the tests used to produce evidence of cognitive sex difference given that not all methods of testing produce the same results (Grossi and Fine 2012: 78). Finally, when there does seem to be evidence of sex differences in behavior these differences are highly sensitive to the social context. Girls whose performance is poorer on math tests when they are reminded of their gender, do better when gender is made less salient (see the discussion of stereotype threat in  section 1.1).