Well, add me to the list. It's like I move my throat down toward my chest, and moving my shoulders helps. It elicits a warm tingly calming sensation, starting from my chest, throughout my body (mainly the torso). A friend suggested I may have the ability to manually stimulate my vagus nerve, which is part of the parasympathetic nervous system. This seems likely, at least certainly close to the truth, and after all this time I've finally found an answer that satisfies me. Instead of just sometimes remembering that not everyone can do this, and wondering what the ability to release this powerful sensation on command could be. Finding this thread of so many others with similar abilities was a relief, and reading about the variations of it is fascinating. Thanks, y'all!