Not sure if this is off topic, but it seems to apply to the discussion. I am not a member of the eastern orthodox church but have some interest in it.
This book I have, defines the body, soul and spirit as such according to their theology. And I bet many Christians have some version of this if not the same idea.
"First, there is the body......the physical or material aspect of man's nature."
"secondly, there is the soul, the life force that vivifies and animates the body causing it to not be a lump of matter, but something that grows and moves, that feels and percieves. Animals also possess a soul, and so do plants. But in man's case the soul is endowed with consciousness; it is a rational soul, possessing the capacity for abstract thought, and the ability to advance by discursive argument from premises to conclusion. These powers are present in animals, if at all, only to a very limited degree."
"Thirdly, there is the spirit, or "breath" of God, which the animals lack. It is through the spirit that man apprehends God and enters into communion with him."
"With his soul (psyche) man engages in scientific or philosophical inquiry, analyzing the data of his sense-experience by means of discursive reason. With his spirit (pneuma), which is sometimes termed nous or spiritual intellect, he understands eternal truth about God or about the logoi or inner essences of created things, not through deductive reasoning, but by direct apprehension or spiritual perception-by a kind of intuition that St. Isaac the Syrian called "simple cognition". The spirit or spiritual intellect is thus distinct from man's reasoning powers and his aesthetic emotions, and superior to both of them."
They have a form of panentheism,
"God is in all things yet is also beyond and above all things", It says, "As Cistercian monk of New Clairvaux has put it, "God is at the core. God is other than the core. God is within the core, and all through the core, closer to the core than the core".
It says, "All things are permeated and maintained in being by the uncreated energies of God, and so all things are a theophany that mediates his presence"...."the whole universe is a cosmic Burning-Bush, filled with the divine Fire yet not consumed".
The Orthodox Way by Bishop Kallistos Ware
That's some definitions and descriptions about those things. Maybe that will help with the discussion on the interaction problem? I'm not saying I necessarily agree with all that, or not.