It is important to realize that newborns are alert and can discriminate sounds.
By one month, infants differentiate speech sounds (phonemes) such as /p/ and /b/ (Trehub & Rabinovitch, 1972). By 6 months of age, infants discriminate two syllable words such as /bada/ and /baga/ and recognize a familiar syllable inside a string of syllables (MacWhinney, 2011).
Infants also discriminate speech sounds of familiar and unfamiliar languages. However, this ability diminishes considerably for unfamiliar consonant contrasts by one year of age (Dietrich, Swingley, & Werker, 2007). Examples of contrasting consonants are pack-back; pie-buy; and rope-robe.
In one experiment, Werker, Maurer, and Yoshida (2010) showed that by 6 to 8 months, infants discriminated most foreign consonant pairs and some foreign vowel pairs. However, by 10 to 12 months, infants barely heard any of the foreign pairs. Examples of vowel pairs are boat and fruit where usually the second vowel is silent. Examples of consonant pairs are /p-b/ and /t-d/ where one letter is voiced using the vibrations of the vocal cords and the other letter isn’t.
The tone in which the language is conveyed also makes a difference. Fernald (1993) found that 5-month-old infants will respond with a smile to a positive tone and not to a negative tone even when the language was unfamiliar.
Last but not least, infants can respond to their own names by 5 months old (Newman 2005).
The above findings highlight the importance of speech interactions with the child and the role of both the environment and experience on speech perception. Widening children’s listening experiences is a window for them to learn many languages and to engage in successful communication styles. Ultimately, high quality listening experiences ensure success in a global world.
Reference:
Boyd, D., & Bee, H. (2012). The developing child (13th ed.). Upper Saddle River, NJ: Pearson.
Future Global Children 