Acoustic and Perceptual Characteristics of Emotional Speech in Adolescents Aged 12–14 with Intellectual Disabilities and Typical Development: Comparative Analysis

The aim of this study is to investigate the manifestation of emotional states in the speech of typically developing (TD) adolescents and adolescents with intellectual disabilities (ID). Emotional speech from 25 adolescents was analyzed during the reading of nonsense texts in the emotional states of “joy — neutral — sadness — anger — fear”. Spectrographic analysis of children's speech was conducted using the software “Cool Edit Pro 2.0”. The following parameters were measured: duration; pitch values (F0); minimum (F0min) and maximum (F0max) pitch values; pitch range values (F0max–F0min); intensity values for the phrase, stressed word, and stressed vowel. A perceptual experiment involving 10 adult listeners was conducted. Differences in acoustic characteristics of emotional speech were identified between TD and ID adolescents: word and vowel duration; minimum pitch values for words and vowels. According to the results of the perceptual experiment, TD adolescents demonstrated a better ability to express sadness and anger in their voice compared to adolescents with ID.