Dorsal vagal state is a shut-down or numb state at the withdrawal end of the nervous system's range, in the polyvagal model.
It is a model, not settled physiology and not a psychiatric diagnosis. In session it names collapse, fog, or gone-ness. Pushing through shutdown is the miss. Smaller, slower, or stop. Persistent unexplained shutdown belongs with licensed care; this is not psychotherapy.
Clients feel numb or far away.