Initially, using the terms I was handed, I talked about the ego as the perceiver and doer/maker, and Spirit as the knower and creator. Over time I referred to the "ego" as the "small" or "child" self and the Spirit within as the "higher" or "greater" Self.
Continuing the work, it became clear that the underlying intelligence of the universe didn't have to be talked about in spiritual or religious terms any more, but that the word Mind applies. Both theory and experiment are making clear the fact that the source, or quantum field out of which all matter and energy arise, is the Akashic field, is the one Mind, underlying and manifesting all that is--all that we generally call reality. And more, that field, that Mind, is present in and through all aspects of reality, including ourselves.
Understanding that, it became clear that each of us--all our cells and all the energy fields around those cells--is part of that Mind, along with everything else that exists. So we can tap into that Mind, that underlying source of all that is. It must be the same thing as the "unconscious" mind that early researchers defined.
For most of my work in this field, I've used Jung's and Freud's framework of 3 aspects of mind: one in which we are aware, one of which we aren't usually aware that governs our body activities and reactions, and one of which we aren't usually aware that accesses the ideals and archetypal images of our culture, of humanity (and possibly even more).
Within that framework, the subconscious mind keeps the body working, the superconscious mind accesses ideals and potentials in the larger mind, and our personal awareness, ego, or conscious mind, is the realm of perceptions, thoughts that link those perceptions, and emotions arising from those perceptions.
So the separation between self and Spirt is dissolved. God, Spirit, is Mind--constantly creating all that is and everywhere present throughout all that is. That means there is one mind and my mind must be part of the whole Mind that is constantly creating all that is. (The "son of God" therefore is all aspects of reality emanating from and sustained by that Mind--which includes all beings, everywhere.)
And that means I'm simply shifting the scope of my personal awareness as I enter different states of consciousness. As I access other aspects of my mind I can access the universal Mind.
Our normal range of personal awareness is delineated by our perceptions: what is entering our sensory system, what our brain has been trained to pay attention to, and what connections our brain has made through repetitions of sensory input. Our emotions are a function of those connections: neurons send impulses to glands that release "molecules of emotion" to cells in the body and we feel happy, mad, sad, glad, hungry, or tired in response to what our brain has said is going on around and within our bodies.
Because our Western Materialist culture teaches us to focus on external sensory inputs and analyse them with the left frontal cortex, we identify with bodies and material objects--we don't know about anything else! In other cultures, children are encouraged to develop their right brain abilities, as well. They learn to sense what is happening in their bodies, and to be aware of their dreams and deeper "feeling" states, which have been called our "inner senses". Their personal awareness, therefore, includes more of the subconscious and superconscious aspects of mind than folks in our culture usually experience.
Still, many individuals in our culture have, over the centuries, been able to demonstrate the power and effectiveness of using "inner awareness" disciplines and practices.
That means that each of us can extend our personal awareness into the subconscious mind and observe and modify the body's processes, including fear responses, heart rate, temperature, and more. It means we can extend our personal awareness into the superconscious mind to observe the nonsensory aspects of our experience, as well. We can remember and interpret dreams, see the relationship between our sensory experiences and our thoughts and feelings, and we can appreciate the non-material aspects of the world around us.
In short, what used to be called "spiritual disciplines" no longer have to be limited to religious practice. They are life practices that make it possible for us to access information and make more useful choices about our whole selves--not just what our physical senses have told us and our previous experiences have led the brain to react to. And what have been called "supernatural experiences" or even miracles, are available to anyone who shifts their personal awareness into the subconscious or superconscious aspects of their own mind and acts accordingly.
So my language about all this has changed. It is no longer the "ego" or "small self" that must be brought into alignment with "Spirit." Instead, we need to retrain, even "rewire" our brains so that we can choose which "programs" it uses in response to sensory input and so we can use the right hemisphere more fully to access the nonmaterial aspects of all-that-is, both within the body and around it. (This is the primary work of Joe Dispenza.)