Multichannel Speech Acquisition and Analysis for Computer-Aided Sigmatism Diagnosis in Children

A novel concept for acoustic data acquisition for computer-aided diagnosis of a common speech disorder (sigmatism) is presented in this paper. We designed and built a data acquisition device enabling repeatable speech signal acquisition in up to fifteen spatially-organized acoustic channels. The system is safe, non-invasive, comfortable, visually attractive to the user, and does not affect the articulation process. It is easy and convenient to use and transport and does not require a specialized measuring room. We collected a large speech corpus containing speech samples from 107 children aged five or six. The data were acquired according to a dedicated protocol. They consisted of multichannel acoustic recordings of selected words containing sibilants and diagnostic descriptions of articulatory features prepared by speech therapy experts. The data acquisition device was examined for responses and repeatability of individual microphones in the presence of various synthetic and human-generated acoustic stimuli. Then, it was verified for its ability to indicate distinctive patterns in spatial energy distribution in different realizations of two sibilants: /s/, /∫/ in three pronunciation categories each, based on collected speech-articulation corpus. The results confirm that a multichannel speech signal can be successfully employed for the analysis of the spatial distribution of airflow during normative or pathological realization of sibilant sounds in children. The method is promising for comprehensive analysis of articulatory features, which follows new trends in the description of speech disorders; such an approach was not employed in speech diagnosis or therapy so far.