Speech

A system of sounds by which humans communicate. Children learn speech through listening to and imitating the speech of others. Speech production originates in 2 regions of the cerebral cortex on each side of the brain. These regions are linked to the centre for language expression (Broca’s area) in the dominant hemisphere. They send signals down nerve pathways to muscles controlling the larynx, tongue, and other parts involved in speech. The cerebellum plays a part in coordinating movements of these parts. Air from the lungs is vibrated through the vocal cords in the larynx. This produces a noise, which is amplified in the cavities of the throat, nose, and sinuses. The sound of the vibrated air is modified by movements of the tongue, mouth, and lips to produce speech sounds.