[Enderz]

"Is it perhaps more like a non-physical zap that's more like an interruption or glitch in consciousness than a ghost physical sensation?"

" So one person's experience with one day off meds was a feeling of floating or vague floating-like feeling of imbalance. That's probably related, perhaps an earlier stage of the phenomenon, but doesn't sound quite the same as the electric shocks people mention they get after quitting. Are the electric shock feelings anything like a rapid (instantaneous?) change in balance, like a shift to zero-g and back?"

These are both pretty good descriptions.

Pretty constant background floaty/disconnected feeling punctuated by sudden, momentary shift of balance feelings that feel like a large number of synapses have fired all at once, usually triggered by relatively minor head or eye movements. Each one leaves you with a very subtle sensation that you've just lost a split second of consciousness and are just suddenly snapping back awake.

They aren't painful at all (so the electric shock analogy breaks down), but after a while can become pretty distracting and annoying (to the point of not being able to concentrate on work, study, or even entertainment).