05/02/2022
When babies are born, their vocal tract is short and their larynx (voice box) sits high up in their throat. Their soft palate and epiglottis (both structure that prevent food from entering the airway during swallowing) are very close together. As they develop their larynx lowers (about 9-10 cm from infant to adult). This change allows for the child to produce sounds that are increasingly similar to adult speech.
Initially, babies make sounds that are reflexive (not consciously controlled) - crying, cooing, laughing.
These are generally vowel sounds (ooh, ahh) that are easier to produce.
As they develop, the changes in their vocal tract and their increasing ability to actively control their lips, tongues and vocal chords allow them to start playing with different sounds. P, b, t, d, k, g and m are typically the first consonant sounds produced.
They learn to master these sounds by repeating them (reduplicated babbling), stinging them together (variegated babbling), adding in new sounds and making long sentences of babble (often referred to as jargon).
Around 11 or 12 months you may start to hear them imitating words that you have said and then using these words on their own.
Babbling will start to reduce as the child learns more and more real words.