Automated Detection and Evaluation of Swallowing Using a Combined EMG/Bioimpedance Measurement System

Figure 3

Biosignal curve. The signal trace above shows typical EMG (mV) and BI (ohm) biosignal curves for a saliva swallow in a healthy subject. BI_start = start of laryngeal elevation, BI_min = maximum laryngeal elevation (BI_min−BI_start), BI_end = end of laryngeal elevation, EMG_start = start of muscle activity, EMG_max = maximum muscle activity during laryngeal elevation, and EMG_end = end of muscle activity. Other swallowing-related parameters are speed of laryngeal elevation ((BI_min−BI_start)/(𝑡(BI_min)−𝑡(BI_start))), extent of laryngeal elevation (BI_start−(𝑡(BI_min)−𝑡(BI_start))), and duration of preparation for swallowing and bolus formation (𝑡(BI_start)−𝑡(EMG_start)).