Here you see a highspeed videoclip of a male singer Grunting. The whole of the supraglottis appeared to vibrate in a random manner. There is also a large glottal gap with apparent laxity of the vocal folds.
High-speed photography is the science of taking very fast pictures. It records fast-moving objects as a photographic images onto a storage medium, often digital. After recording, the stored images can be played back in slow-motion. Therefore all sound is removed since it would be also slow-motioned while playback.