As units of pure consciousness we express through the brain and nervous system.
At the innermost core we are clear, immortal being without conditioning. The body and mind serve as a vehicle for the Soul and, as such, pure consciousness in the unaware state is conditioned by impressions that accumulate and are inherent in the body/mind. As a result we are forgetful of our true identity as the Self or eternal witness.
This primal awareness, the life of our life, is always subtly present in the background. In this sense awareness is always the same; you have the same awareness now that you had as a child, just different thoughts/ideas/beliefs accumulated and scattered about the different levels of mind. Nevertheless, awareness remains the same—ever pure, witnessing. The goal of spiritual practice is to return to, and consciously experience, this pure awareness.
Our birth is but a sleep and a forgetting:
The Soul that rises with us, our life’s Star,
Hath had elsewhere its setting,
And cometh from afar:
Not in entire forgetfulness,
And not in utter nakedness,
But trailing clouds of glory do we come
From God, who is our home:
Heaven lies about us in our infancy!
– William Wordsworth
Note: The words Divine Being, Supreme Being, consciousness, truth, God, absolute, Source, ultimate Reality, essence or core of our Being, all refer to the same thing and are used interchangeably throughout these sutras.