Hören lernen - die Bedeutung der ersten Lebensjahre

Zusammenfassung

Bei Geburt ist das menschliche Gehirn weitgehend unreif. Reifungsprozesse umfassen das Auswachsen von Axonen, die Bildung von Markscheiden und die Bildung synaptischer Verknüpfungen. Obwohl das Innenohr des Menschen schon intrauterin ausreift, gilt dies für die zentralen Bahnen nur bis zum Hirnstamm. Die weiteren afferenten Verbindungen bilden sich erst später, die meisten bis zum fünften Lebensmonat. Funktionell ist das zentrale Hörsystem erst zur Pubertät voll ausgereift. In der Entwicklungsphase sind die ersten beiden Lebensjahre besonders wichtig, da in dieser Zeit die Neubildung von Synapsen maximal ist. Dies ist für hörgeschädigte Kinder von besonderer Bedeutung, da dieser Umstand zu frühen therapeutischen Bemühungen zwingt. Genetischer Hintergrund für die Entwicklung von Lautsprache ist offenbar das Gen FOXP2.

Abstract

At birth the human brain is immature. Maturation requires the sprouting of axons, myelinization and the formation and stabilization of synapses. Although the inner ear is functional already between the 26th and 29th week of fetal life, during this period afferent central connections only reach up to the brain stem. The further afferent pathways reaching finally the auditory cortex are formed later up to the 5th month of life. Nevertheless, they are not fully functional then. Final functional maturation takes up to the age of puberty. The first two years of life, however, are most important for central maturation, as most new synapses are formed during this period. It is thus mandatory to start treatment of hearing impaired children early during this period. Genetic background for development of speech and language is apparently the gene FOXP2.

Schlüsselwörter

Hirnreifung - sensible Perioden - Sprachanalyse

Key words

cerebral maturation - sensitive periods - speech and language

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