Newport and Supalla studied ASL acquisition in deaf children differing in age of exposure ; few were exposed to ASL from birth , most of them first learned it at school .
Studies of deaf children learning American Sign Language ( ASL ) have fewer methodological weaknesses .
Newport and Supalla studied ASL acquisition in deaf children differing in age of exposure ; few were exposed to ASL from birth , most of children first learned American Sign Language at school .
Studies of deaf children learning American Sign Language ( ASL ) have fewer methodological weaknesses .