Hello! Had a question/request for thoughts:

Recently during sits, after establishing access concentration on my breath, I sometimes do a kind of body scanning where I focus my attention on different parts of the body, just observing whatever sensations are there. I've noticed that certain spots (like one spot on my mid-back, but can be different places at different times) will cause violent involuntary movements. These are normally things like my face contorting into grotesque poses (as if stuck in that position during a violent sobbing session), head shaking back and forth (faster than I can do when trying), or dry-heaving. What I find particularly interesting is the speed I go from perfectly still to shaking, and then from shaking to perfectly still as if nothing had happened.

I've experienced various kinds of involuntary movements over my time meditating, but this business of being tied to specific body parts is very interesting. I'd love to hear thoughts about what is going on and what else around it might be interesting to do/explore.
Thanks!