I wonder what the explanation is for that working.
There appears to be some sort of nerve complex where they are pressing. I severely damage my inner ear on the right side years ago scuba diving. Mostly deaf on that side.
If I press in just the right spot as these folks were doing, I get a "bubbling" sound in my "ear". Obviously no sound at all, just stimulating some nerve to send an auditory signal?
Have no idea FRiend!