title: Language experienced in utero affects vowel perception after birth: a two-country study.
abstract: OBJECTIVE
  To test the hypothesis that exposure to ambient language in the womb alters phonetic perception shortly after birth. This two-country study aimed to see whether neonates demonstrated prenatal learning by how they responded to vowels in a category from their native language and another non-native language, regardless of how much postnatal experience the infants had.
  
  
  METHODS
  A counterbalanced experiment was conducted in Sweden (n = 40) and the USA (n = 40) using Swedish and English vowel sounds. The neonates (mean postnatal age = 33 h) controlled audio presentation of either native or non-native vowels by sucking on a pacifier, with the number of times they sucked their pacifier being used to demonstrate what vowel sounds attracted their attention. The vowels were either the English/i/or Swedish/y/in the form of a prototype plus 16 variants of the prototype.
  
  
  RESULTS
  The infants in the native and non-native groups responded differently. As predicted, the infants responded to the unfamiliar non-native language with higher mean sucks. They also sucked more to the non-native prototype. Time since birth (range: 7-75 h) did not affect the outcome.
  
  
  CONCLUSIONS
  The ambient language to which foetuses are exposed in the womb starts to affect their perception of their native language at a phonetic level. This can be measured shortly after birth by differences in responding to familiar vs. unfamiliar vowels.
authors.affiliation: Pacific Lutheran University, Tacoma, WA 98447, USA. mooncm@plu.edu
authors.forename: Christine
authors.initials: C
authors.lastname: Moon
authors.forename: Hugo
authors.initials: H
authors.lastname: Lagercrantz
authors.forename: Patricia K
authors.initials: PK
authors.lastname: Kuhl
mesh_terms: D005260:Female; D047109:Fetal Development; D006801:Humans; D018730:Infant Behavior; D007231:Infant, Newborn; D007804:Language Development; D010700:Phonetics; D011247:Pregnancy; D013067:Speech Perception; D013548:Sweden; D014481:United States