Your seemingly innocuous question could take over 100 pages of text to answer in detail! I am no expert but have some deep-rooted opinions and convictions. First, we are talking about “mind”, but what exactly is mind? I would consider it best described as an energy (or radiation) field, that enables interface of human will with material environment via thought and physical body which includes brain. I would imagine it has several operational modalities, e.g. body alive/brain awake, body alive/brain asleep, body alive/brain unavailable (e.g. comatose, damaged, unconscious etc), body dead/brain dead, in this last case I think the energy field that is mind would persist.

So to answer your question of what “space” mind is constrained, I would imagine it’s something of a Heisenberg uncertainty, depending on the state (modality) it could be mainly concentrated across certain regions of the brain (as waves bound by brain matter) the region being dependent on the modality mentioned above, or for the final case (body dead/brain/dead) it would be centred in (spread across) a “space” the description of which lies outside the current boundaries of classical physics (to my knowledge), but to which it is constrained by virtue of laws governing it’s interaction with other radiation energies and fields that constitute our Universe.

I wanted to be brief but have already crossed 200 words! I am seeking better understanding of these brain, thought, mind, emotion, individuality, psyche, collective mind questions, and spend free time probing quantum physics for possible correlates and solutions.

In physics there are many mathematical ways of defining spacetime, of which the 3-dimensional space of our physical world is but a a subset. I would say mind does occupy space, but not the 3-dimensional space of the physical world we are familiar with