ASA 127th Meeting M.I.T. 1994 June 6-10

5pSP47. The asymmetric structure of the infant's perceptual vowel space.

Francisco Lacerda

Inst. of Linguist., Stockholm Univ., S-106 91 Stockholm, Sweden

This paper reports a study of the infant's perceptual sensitivity to F[sub 1] and F[sub 2] changes occurring in the central region of an adult male's vowel space. The data were collected from a group of 16 Swedish infants whose ages varied from 6 to 12 months. The infants were tested with the headturn procedure in their ability to discriminate variants of a reference schwa vowel. Four variants were generated by introducing a fixed increment or decrement (in Bark) along either F[sub 1] or F[sub 2]. The results are compatible with previously reported data obtained for vowel contrasts in the low/back region of the vowel space [F. Lacerda, J. Acoust. Soc. Am. 93, 2372(A) (1993)]. Thus the general notion that there is a perceptual asymmetry favoring F[sub 1] differences during the early stages of vowel perception is supported by the present results. The paper attempts to argue that the early structure of the infant's vowel space might be influenced by the combined effects of both the perceptual dominance of F[sub 1] contrasts and the infant's larger articulatory precision along the open/close than along the front/back dimension. [Research supported by The Bank of Sweden Tercentenary Foundation, Grant 90-0150.]