Normative of Motor Speech Profile in Typical Kannada Speaking Adolescents

Abstract

This study investigated articulatory motor performance in Kannada-speaking adolescents using the advanced Motor Speech Profile (MSP) module of the Computerized Speech Laboratory. The main purpose of this study is to establish normative data on 80 (N =80) adolescent Kannada native speakers on Motor Speech Profile in the age range of 10-18 years with two subgroups namely 10-13 (n = 40) and 14-18 years (n = 40) with 20 males and 20 females across the groups. The MSP module assessed five protocols: diadochokinetic rate, second formant transition, voice and tremor parameters, intonation stimulability, and standard syllabic rate. Results showed that DDK rate increased with age across specific syllables, with significant differences between adolescent and adult males. Females stabilized earlier and had lower variability. In F2 transition, females showed higher F2magn and F2aver values, and males showing higher F2reg and F2rate. As expected, fundamental frequency (F0) was higher in females. Males showed decreased F0, with marginally higher variability, in young adolescent males. Tremor related parameters were higher in males compared to females. Intonation stimulability mirrored voice and tremor trends. Females exhibited higher pitch range and variability, indicating greater pitch control. Males showed higher standard syllabic rate with age suggesting age related changes in speaking rate. Several parameters measured across protocols were higher in adolescents than adults indicating continuous improvement across phonatory and articulatory motor control. The normative developed from this study could be used to judge the speech motor variations across phonatory and articulatory dimensions, thereby aiding in diagnosing and treating speech motor disorders.