Dar, M.
University of York
The present study tested infants from English-speaking homes to examine effects of development on cross-language speech perception. Werker (1981, 1984) showed that 6-8-month-old infants are able to discriminate non-native speech sounds that adults cannot discriminate, but by 10-12 months the infants were no longer able to make the discrimination. According to Kuhl (2004, 2008), this decline in discrimination is due to infants? increase in native-language exposure, which leads to ?neural commitment? to the native language at this age. Many studies have shown a decline in discriminatory abilities of infants for non-native contrasts between 6 - 12 months of age but no study to date has tested a contrast in affricates in a cross-language perception test. Also, very little attempt has been made to show whether the experimental order of presentation of stimuli affects infants? performance. An aspirated - unaspirated contrast of Urdu /t?/ - /t?h/ was selected based on a pilot study with 20 English-speaking adults who were tested on a number of Urdu contrasts not found in English to identify the most difficult. Twenty-four 7- and 11-month olds were tested in a habituation procedure. Half of the infants were habituated to the voiceless aspirated affricate and tested on the contrasting voiceless unaspirated affricate while the remaining infants experienced the reverse pattern. Discrimination was assessed by comparing mean looking time during the last two habituation trials to mean looking time during the first two trials of the test phase. In agreement with the literature, the results indicated that 6-8-month-olds could discriminate the affricate pair but 11-month-olds could not. Infants presented with the non-prototypical consonant (the aspirated affricate, which does not occur in English) in the habituation phase showed better discrimination in the test phase than the infants presented with the prototypical consonant in the habituation phase.