International Brain of Mystery - Adventures in Linguistics

The name’s Bond…Baby Bond. Your incredible brain can distinguish the speech sounds of seven thousand world languages. Whoops – I meant you had this international, globetrotting skill but it ended when you were six months old!

Up until six months of age, infants with normal hearing can differentiate all the units of sound, called phonemes, that humans can make. There are 3,183 phonetically distinct speech sounds in just thirty percent of the world’s languages.

Typically, languages usually have around 40 phonemes:

!Xóo: 158 phonemes (the most) – spoken by people between Botswana and Namibia
Hindi: Around 44 phonemes
English: Around 44 phonemes
Russian: About 42 phonemes
Swahili: Around 36 phonemes
Mandarin Chinese: Around 26 phonemes plus tones
Spanish: Around 24 phonemes
Rotokas: 11 phonemes (the least) – spoken in Papua New Guinea

Around six months, babies start to “tune out” speech sounds from any language they do not hear regularly and hear from an actual person (e.g. TV and recorded audio don’t work). This reduction is called perceptual narrowing and it is a critical step in early language acquisition. Infants have to learn to identify which 40 or so phonemes matter for their native language. They do this by statistically analyzing the distributions of sounds that they hear. No wonder they need naps!

Once a baby knows which speech sounds matter, they make dedicated neural networks that “code the patterns of native-language speech” so it’s easier and faster for them to recognize which speech sounds match existing patterns. This is called native language neural commitment (NLNC).

FYI – Here are the 44 phonemes in English and their International Phonetic Association symbol:

Consonants

/b/ – as in bat
/d/ – as in dog
/f/ – as in fish
/g/ – as in goat
/h/ – as in hat
/j/ – as in jam
/k/ – as in kite
/l/ – as in lamp
/m/ – as in man
/n/ – as in net
/ŋ/ – as in ring
/p/ – as in pig
/r/ – as in rat
/s/ – as in sun
/ʃ/ – as in shoe
/t/ – as in top
/tʃ/ – as in chop
/θ/ – as in think
/ð/ – as in this
/v/ – as in van
/w/ – as in wet
/j/ – as in yes
/z/ – as in zoo
/ʒ/ – as in treasure
/dʒ/ – as in judge

Vowels

/æ/ – as in cat
/e/ – as in bed
/ɪ/ – as in sit
/ɒ/ – as in hot
/ʌ/ – as in cup
/ʊ/ – as in put
/iː/ – as in see
/ɑː/ – as in car
/ɔː/ – as in saw
/uː/ – as in blue
/ɜː/ – as in bird
/eɪ/ – as in say
/aɪ/ – as in my
/ɔɪ/ – as in boy
/aʊ/ – as in now
/əʊ/ – as in go
/ɪə/ – as in ear
/eə/ – as in air
/ʊə/ – as in tour
/ə/ – as in sofa (schwa sound)

ˈbaɪ ˈbaɪ ˈbeɪbi! = bye bye baby!

Read More:

Quadir, Shamim. February 21, 2020. Speech sounds in the world’s languages. City University of London. https://www.city.ac.uk/news-and-events/news/2020/02/speech-sounds-in-the-worlds-languages.

www.phoible.org

Gawne, L. & McCulloch, G. (Hosts). (2017, September 21): Sounds you can’t hear – Babies, accents, and phonemes (No. 12) [Audio podcast episode]. In Lingthusiasm. Lingthusiasm – Lingthusiasm Episode 12: Sounds you can’t hear.

Kuhl, P. Early language acquisition: cracking the speech code. Nat Rev Neurosci 5, 831–843 (2004). https://doi.org/10.1038/nrn1533.

IPA i-charts (2024)