ASA 124th Meeting New Orleans 1992 October

3pPP1. Newborn discrimination of speech-like sounds.

Angela G. Shoup-Pecenka

Gail E. Walton

N. J. A. Bower

T. G. R. Bower

Callier Ctr. for Commun. Disord., Dept. of Human Dev., Univ. of Texas---Dallas, 1966 Inwood Rd., Dallas, TX 75235-7298

Knowledge of the development of auditory sensation and perception is of unquestionable theoretical and practical importance. A procedure for behaviorally assessing auditory perception in newborns, based on sucking, has been developed. Neonatal thresholds to tonal stimuli, obtained with this measure, have been reported [A. G. Shoup-Pecenka et al., J. Acoust. Soc. Am. 90, 2297 (A) (1991)]. For the present study, speech discrimination thresholds were assessed in the well-baby nursery of a county hospital. The stimuli used were a forward English /u/ and the same sound played backward, at various intensities (0, 5, 10, 15, and 20 dB re:normal adult threshold). These stimuli were chosen because newborns have been reported to discriminate between them at a suprathreshold level [A. Weintraub, 8th International Conference on Infant Studies (1992)]. Using a procedure similar to the one for obtaining tonal thresholds, the level at which the neonate could determine the difference between two speech sounds was determined and compared to the infant's 1--3 kHz threshold. Results suggest that speech discrimination thresholds for newborns are comparable to those for adults.