As a result of the experiment on English-speaking children, Musolino (1998) finds that in child language, unlike in adult language, the scope relation between quantifiers and Neg is in isomorphic relation to their overt c-command relation or their linear order. Musolino (1998) explains this isomorphism observed in child language by elaborating the inventory of syntactic categories in UG and assuming that children obey the Subset Prindple.
Based on the results of the experiment which investigates how Japanese-speaking children interpret negative sentences containing quantifiers in the object position, this presentation has pointed out that children compute the scope relation between quantifiers and Neg not on the basis of their overt c-command relation but of their linear order. This presentation has also pointed out the problem of Musolino's (1998) explanation for isomorphism, and has proposed that isomorphism in child language can be attributed to the Isomorphism Principle (cf. Hyams (1986), van Kampen (1996)).