I had a sense of repulsion, which is quite uncommon if you know me. I'm repelled and admired about the direction you took. There's evidence of mastery in your detailed and clear writing style. You also have the capability of embedding the story with non-banal ethical reflections, irony, and paradoxes on mankind's nature. Also, in doing this there's never that common tradeoff between musings and plot at the disadvantage of the second. Instead, what I see is a plot enriched and reinforced by the existential questions of the third person omniscient you chose. This is a clear example of a though piece where the raw scenes are functional to convey a message and make the reader think. My same way, when I write, to intend horror and in general "strong" passages.
Here are some of the key points which I took into consideration for my analysis:

He imagined their grimy fingers tangling into the hair of his severed scalp.

But the head can feel.

Wasn’t this all just a Grand Experiment, then?

Satisfied with her good deed and even better intentions, the aide whisked out of the room. Again, 19-B lay in darkness with nothing but his manufactured thoughts for company.