At what age can people differentiate sounds based on phonetic category even when such distinctions are not present in their native language? At what age does speech perception become modified?
Werker and Tees conduct experiments to determine at what age people stop differentiating sounds of different phonetic categories without the influence of their native languages. Different researchers have shown that infants can differentiate a set of phonetic sounds (Werker and Tees 49). Their ability to do this is said to reduce when they are exposed to certain linguistic experiences. It is different for adults; they perceive only the sounds that ...