Temporal Change by Measurement of Swallowing Sound

In Japan, a country with an unparalleled super-aged society, the seventh leading cause of death is aspiration pneumonia at 2.7%, with the overall death rate due to pneumonia being 9.9%. The probability of aspiration of food related to the degree of swallowing function is unknown. In this study, multichannel analysis was used to measure the time gap between signals from multiple microphones when recording the sound of swallowing. In addition, the change in timing of sounds I, II, and III was confirmed depending on the amount and viscosity of swallowed food. In the multichannel analysis, a slight deviation of the signal occurs for each microphone, suggesting that the index can be extracted from the multichannel analysis. It was determined that when the amount of material to be swallowed and the viscosity change, the time of the entire set of sounds and that of each section changes accordingly.