WORD-INITIAL VOICING IN THE PRODUCTIONS OF STOPS IN NORMAL AND PRETERM ITALIAN INFANTS

It has been traditionally held that developmental anomalies in languag e acquisition are more frequent in neonatologically at-risk subjects, There is some suggestion that proficiency in phonology is correlated w ith motor control development. The purpose of this paper was to compar e the patterns of acquisition of the control of the acoustic-phonetic cues for voicing in the speech of premature infants and controls, The measure studied was initial stop consonant voice onset time (VOT), whi ch is known to be the most reliable acoustic cue for the distinction b etween voiced and voiceless stops. The total population of the study c onsisted of 7 infants born at less than 37 weeks gestation and a contr ol group of 7 infants born full-term at normal weight; 7 adults, aged 24-26 years, also participated. Each child was recorded under standard recording conditions saying words contrasting labial, dental and vela r voiced and voiceless initial stops, Elicited word productions were c ollected monthly from infants, at different age levels, ranging from 1 8 to 21 months. The results show that the subjects are more advanced i n the acquisition of the appropriate VOT values for the voiceless than for the voiced consonants, This difficulty may be related to the incr eased neuromuscular control and more complex muscle activity necessary for maintaining voicing during the closure, especially for velar stop s, It is important to recognize the possibility that increased variabi lity in preterm children may be related to some neuromuscular immaturi ty.