First off, despite religious assertions to the contrary, we don't know if trees or animals have souls or not. If we posit that the soul is some kind of coherent energy field, one we have yet to learn to detect, it would be logical to guess that it would be affected by the neuro-electrical properties of the brain. Or conversely, if the soul is in reality a energy based life-form, then its field may be affecting the brain's neuro-electrical properties. This energy field may also be a basis behind psionics, assuming one believes in them.
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As to the issues you bright up, the interface between the body and soul could be as if the soul were a recording device or it could the equivalent of camera/microphone/sensors/whatever. In other words, damage to the brain results in improper input/output, but doesn't result in the soul itself becoming damaged.
The varity of potentials is vast especially when we review how much we have discovered that exists, that we were never aware of before. So then how much more is out there, affecting the universe around us, that we haven't even discovered, yet alone learn how to measure and/or manipulate.
By the OP, you wouldn't know that. For all you know there is no life after the next one, and/or the next one has a limited span like the current one does. You don't even know that you get to carry memories over from one life to the next, or maybe you do but you can't access them consciously. There is a wide range of potentials available by the way the OP is written.