Characterization of Masticatory and Swallowing Sounds Using Wavelet Analysis

Abstract

The evaluation of swallowing via swallowing sounds for preventing aspiration pneumonia has been reported previously; however, the distinction between masticatory and swallowing sounds has not been studied. Therefore, this study aimed at distinguishing mastication and swallowing based on the sounds produced during eating. Daubechies wavelet analysis of the sounds generated when eating samples of almonds and white rice of different hardness and viscosity values was performed. Different features were found to be present in the masticatory and swallowing sounds. During chewing sounds, the frequency changes to a higher frequency. This feature was found in 78% of the masticatory sounds obtained in the experiments. Swallowing sounds, on the other hand, change to a lower frequency. This feature was found in all swallowing sounds obtained in the experiment. Based on this feature, distinguishing between masticatory and swallowing sounds may be possible.