A great way to understand consciousness is to study those that increase consciousness in others.
A mother who cajoles and exchanges smiles with her baby. A teacher who transmits knowledge. A neurologist who awakens a comatose by electrostimulations. A mystic who shares holist ideas.
There are many ways to define an increase in consciousness. Is there anything in common in all these ways that helps us to understand what consciousness is fundamentally?
Each way is anchored in a different level of information. This is why the consciences they describe appear so dissimilar. The only thing in common is the actual increase in consciousness, regardless of the medium of information.
This common feature is the addition of additional levels of information. We readily call this phenomenon an 'enlargement' of consciousness. But it's more of a stack. Higher-level information synthesizes previous ones.
The baby includes more elaborate signals from the mother. The teacher allows his students to access a higher class. The neurologist restores greater integration of neural networks. The mystic creates a higher observation of the self within a whole.
Consciousness is a stack of layers, from those laid by the mother to the delicate veils laid by the mystics on the nudity of our soul.