Deaf education; Bicultural education (Deaf education) ; Bilingual education (Deaf education) ; Spracherwerb (Schriftsprache) ; Language acquisition (written language) ; Kindersprache (Schriftsprache) ; Child language (written language) ; Schrifterwerb (psycholing.) ; Written language acquisition (psycholing.) ; Writing (neuroling.) ; Spracherwerb und neurologische Entwicklung; Language acquisition and neurological development; Sprache und Denken (Ontogenese) ; Language and thought (ontogenesis) ; Cognitive development; Language acquisition and cognitive development