Speech

Human speech has become a system of communication requiring coordination of voice, articulation and language skills. Voice is produced by the movement of air which vibrates through the vocal cords.

Vocal chords are made of elastic connective tissue covered by folds of membrane. The pitch of your voice is controlled by the modification of the muscles that shorten the cords pulling them tight for high pitch and slack for low pitch.

Articulation is the modification of airflow. Speech is articulated by the movements of the tongue, lips, lower jaw and soft palate. Vowels come from voiced excitation of the voice tract. Articulators are kept static and all sound radiates from the mouth. Nasals are generated when the tongue is raised and the soft palate is lowered which reduces the oral passage. Plosives are generated when the vocal tract is closed by the thr tongue or lips and then the pressure built up is suddenly released. Fricatives are formed by partially restricting the vocal tract by the tongue or lips.