I think that the fundamental meaning of anicca or change is key to understanding mind, awareness, memory, and consciousness.
Awareness encompasses the range of active mental content inclusive of sense channels and memory responses to active mental content - the memory responses include all momentary aspects of thought and feelings. Whatever is in Awareness becomes interlinked into memory moment by moment.
The mind (brain) evolved through a 1/2 billion years to enable familiarity reflexes to guide movement of bodies in the world. Memory enables the familiarity reflex for what the body encounters, so that we can find our way, and in humans and other complex animals, familiarity also applies to thoughts as part of the terrain that the body encounters - memory responses (familiarity) includes body movement as well as ideas, words, names, general feelings and complex ideas and sequences of them.
When you see or smell something (i.e. become aware of it) you will reflexively think of something that you are familiar with which is attached to that appearance or smell leading to citta - citta - citta… that is the way of mind.
In Buddhism we cultivate awareness by scheduling and fulfilling meditation tasks, studies, and devotional activities. The more we practice the more familiar we become with this cultivated awareness practice (the cultivation of active mental content), and the more the cultivated mental content sustains our ability to find our way.
The mind also evolved to escape predation, or to notice sustenance (sometimes prey) in the environment. At a very basic level, below the function of awareness and memory formation and reactivation (familiarity), the mind will suppress active mental content moment to moment if that content is not changing thus enabling detection of what has moved or changed. What is left over in active mental contents after eliminating that which is static or unchanging becomes part of awareness and then memory.
We cannot control the highly evolved change detection that drives awareness and memory formation citta by citta: anicca is out of our field of influence, but by using practice we can cultivate awareness beneficially.
I believe that change or fluctuation is also a physical reality in all aspects of the world, but as regards mind and citta, change is a driving force to which we must adapt in our cultivation of awareness practice.
The relationship of annica to annata is that there is no self which adapts to change other than the practiced familiarity that was cultivated, or in the case of non-practitioners, there is no self other than individual familiarity that automatically forms with each mind moment (citta).