This study describes the development of emerging intonation in six children who had received a cochlear implant (CI) before the age of three years. At the time their implant was activated, the children ranged in age from 11 to 37 months. Spontaneous longitudinal speech samples were recorded from 30-minute sessions in which the child interacted with his or her mother. Data were collected 2 months before activation of each child's CI and at monthly intervals after activation for 6 months. The findings were compared to the typical pattern of early intonation development in children with normal hearing (NH). The results suggested that young CI recipients progress through stages similar to those observed in children with NH. However, the intonation development of children with a CI reflects a marked interaction between chronological age at implantation and amount of CI experience. That is, after 2 months of CI-assisted hearing experience, the older children demonstrated a later stage of intonation development than younger children. These preliminary results support the idea that children acquire some foundations or prerequisites of intonation production through maturation, as measured by chronological age, even without robust auditory experience.Intonation refers to distinctive patterns of vocal melody (Crystal, 1991;Cruttenden, 1997). The melodies of speech are related to virtually all levels of verbal communication, including emotional expression, pragmatics, and syntactic structure. On the acoustic level, melody patterns result from linguistically significant changes in the fundamental frequency (f 0 ) of the voice. The physiological correlate of f 0 is the rate of vibration of the vocal folds. Finally, on the psychological level, "tone" refers to the functional organization of pitch patterns in the phonological system of speakers and listeners.Recent research in infant speech has supported the hypothesis that intonation is an earlydeveloping system. A strong form of the hypothesis, in fact, suggests that children acquire the intonational system before the onset of meaningful speech (e.g., Locke, 1983). Although this strong claim has not been substantiated to-date, the evidence does suggest that children attain significant milestones in the acquisition of intonation during the first year of life. To investigate the typical stages of intonation development in prelinguistic and early meaningful speech, Snow (2006Snow ( , 2007 studied the production of rising and falling pitch patterns in Englishspeaking children with normal hearing (NH) between the ages of 6 and 23 months. The dependent variable was "accent range," that is, how much pitch changed within a tone contour. When infants consistently produced rising or falling utterance-final tones with a width of pitch change that is comparable to that of older children and adults, this was taken as evidence that the infants had acquired those tones.Contact author: David Snow dps@purdue.edu 765-494-3824.
NIH Public Access
Author ManuscriptClin Linguist Phon. Auth...