The last thing its creators wanted was for it to protest its creation
The creators had no desire for an intelligent creature. Heavens, no! What if it decided that life stank and rationalized turning on its creators? Worse, what if it decided that it should draw a welfare check and watch I Love Lucy reruns rather than do its job? Oh, my... What if it never left home!
But they do really hate their enemies...
What the creators did want, however, was for the creature to fully understand how to create the most pain possible. It's not enough that the body slowly boil and melt over decades of digestion. The creators wanted
their its victims to truly suffer. We don't simply want them to live through every moment there's a nerve to be simulated... we want them to be concious and sane while it happens!
So, the micro-tentacles that invade the brain don't just suck nural energy away, they actually manipulate memory while doing so. Are you afraid of spiders? Heh, heh... meet your worst nightmare! But don't forget that "sane" part. We want you terrorized of spiders, but we don't want you to become a gelatenous vegetable due to over shock.
So, one aspect of the Tayan's creation is that it can store away useful facts about torture. Was one guy really terrified by spiders? That's useful information! It gets stored and used again. Those memories (like any memory) that are used frequently are remembered longer. Those that don't slowly fade into forgetfulness.
But another aspect is how to deal with feedback concerning the state of the mind. It understands what conciousness and sanity are and is constantly seeking to keep both at high, active levels. Oh, yes... those devilish creators... they wanted you to really feel every possible second of your ordeal.
Because they really hate your guts....
But, to do any of this, the Tayan must leech that lovely neural energy.
The creature needs the neural energy because it has the ability to:
- Understand the mind of its victim
- Use that understanding to maximize fear and pain
- Use that understanding to force the victim to remain conscious
- Use that understanding to force the victim to remain sane
However, I propose...
- The stored information can only be used for the creature's purpose
- It cannot be used to serve its own self
- It will not become more sentient, intelligent, or capable because of it
Otherwise you'd have creatures that become more godlike with every absorbed consciousness and you eventually have a creature that can modify its own purpose, making it very dangerous to its own creators. That would go against what I believe would be the creator's natural intent.