The Physical Basis of This and That

The research result that "space is coded in two major maps, one for peripersonal space (the space that surrounds the body, where we can reach for objects and grab them), and the other one for extrapersonal space (the space we can't reach). New data...show that some mirror neurons change their responses to observed action on the basis of where the action is located." (Marco Iacooni, "Mirroring People", 2008, Picador, New York, p.277) may imply the physical basis for the fact that we have more than 2 types of demonstrative pronouns.