Event related desynchronization. Significant activation in group analysis is shown (p < 0.001). Changes in the beta-frequency-band during swallowing execution compared to the resting stage. a) Significant cortical activation after volitional swallowing without oropharyngeal stimulation. b) Cortical swallowing activation after oropharyngeal stimulation is broader in both hemispheres. The color bar represents the t-value.