Preverbal communication; Prespeech; Fötus (Sprachverständnis) ; Präverbale Kommunikation; Protolanguage (language acquisition) ; Prelexical period (language acquisition) ; Spracherwerb und neurologische Entwicklung; Language acquisition and neurological development; Sprache und Denken (Ontogenese) ; Language and thought (ontogenesis) ; Cognitive development; Language acquisition and cognitive development ; Hören (phonet.) ; Hearing (phonet.) ; Auditory phonetics