Dynamics of the Duration and Frequency Characteristics of Vowels during the First Seven Years of Life in Children

Abstract

One direction in studies of the ontogeny of speech con-sists of investigations of the establishment of the acousticcharacteristics of speech in children [13, 15, 23, 24, 34]. Moststudies using material from different languages haveaddressed analysis of the early vocalizations of babies [3, 14,22]. There are only occasional reports on the acoustic char-acteristics of the speech of children of preschool age [13, 15]and virtually none using Russian-speaking children [21]. Thehistorically established language specifics of articulatorypositioning do not allow data obtained using other languagesto be transferred directly to Russian.Our series of studies has addressed the establishment ofthe acoustic aspect of speech using material in Russian andcovers the period from the appearance of vowel-like sounds[3, 4] to clearly pronounced words and phrasal speech inchildren of preschool age [27, 28, 29]. However, each ofthese studies involved analysis of the acoustic characteristicsof vowels at a specified age.The selection of vowels as study material was based ontheir importance for understanding the acoustic propertiesof speech. Vowels from first in the sound repertoire of chil-dren, in adult speech. The formant frequencies of vowelsconstitute the acoustic keys for the perception of vowels andconsonants. Voice pitch and the prosodic characteristics ofspeech are also due mainly to the properties of vowels.Our previous studies involved not only analysis of theacoustic characteristics of vowels, but also aimed to describethe sound repertoire of children, the specific features of therecognition of children’s words and phrases by adults, andthe formation of phrasal stress.The aim of the present work was to follow changes inthe acoustic characteristics of vowel-like sounds from thevocalizations of babies and vowels from the words of chil-dren in the first seven years of life.