Again, if you stare at that video, there's not too much you'll be able to see, but once we magnify the motions 100 times, we can see all the motions and ripples in the neck that are involved in producing the sound.
元の映像を見ても ほとんど動きは見られませんが 動きを100倍拡大してやると 発声に関わる首の部分に 波のような動きが広がっているのが 分かります