I've taken high doses of LSD and definitely experienced very similar entities ... Normally there are many types of forces and drives that are each "speaking to us" constantly... we just never perceive them as personifiable or distinct -- it's just "our inner voice".

My thought is that the brain stores something analagous to a kind of a big fuzzy hierarchical hash table between sensory inputs and nervous system response (pleasure/pain). LSD/DMT allow us to traverse these hashtables in ways that are not usually possible. (DMT especially...)