Yes, neither perception nor non-perception is again a perception. (Ref: Ajahn Brahm's book: Mindfulness, Bliss and Beyond) Beyond the 8th jhana is norodha samapatti, where all perceptions and feelings end. My assumption after some study of documented information/scripture is that the mind as a sense organ is not active during this state. Basically, the mind stops. So there is no rational way for a person to perceive during this absorption. All sensory activities are shut off. Realization should happen when arising from this state; when the mind starts again. A person wakes from this state either as an anagami or an arahath according to books. Naturally, after getting direct experience as to how things build up, I don't think there can be any doubts left in the mind.