So nirodha is the cessation of perception and feeling. One doesn’t feel anything, nor do they perceive anything. Isn’t this just like deep sleep?
The difference, IMO is the sense of continuity.
Even with the deepest sleep, one wakes knowing ‘time has passed’ because the Citta is always aware of its own existence.
Cessation experience however is all about turning the Citta ‘off’ and then having it turn ‘on’ again. There is a ‘break’ in the timeline of existence.
Wise reflection on this experience sheds light on the nature of conditioned experience vs Nibbana.
AN10.7
“One perception arose and another perception ceased in me: ‘The cessation of existence is nibbāna; the cessation of existence is nibbāna.’ Just as, when a fire of twigs is burning, one flame arises and another flame ceases, so one perception arose and another perception ceased in me: ‘The cessation of existence is nibbāna; the cessation of existence is nibbāna.’ On that occasion, friend, I was percipient: ‘The cessation of existence is nibbāna.’”
I have seen explained that in cessation of perception and feeling also bhavanga is absent. In deep sleep one is said to be in a state of bhavanga. In a state in which cognition is not absent but is brought back to a very basic level.