Another description can be found here >> cycle
The insight cycle is easy to explain under the Theory of Enlightenment framework.
I will mix metaphors here: an xmas tree made of smaller xmas trees, and an irrigation system.
The tree is the top-down structure, and the irrigation system is the bottoms-up data-flow.
What happens is you deconstruct the tree, using isolation and destabilisation techniques. Art and cycling or noting and meditation.
The star on the tree is L5: your metacognition. You steer this. You say ‘I do not want the star of greed because it causes me pain; I will make another one’.
You begin making incremental change in your scaffold.
This destabilises your L4 worldview; your ‘static self’, which was build under the old model. The bungee snaps.
The cycle after that is how the brain builds, tests, destabilises, and consolidates new structures to move toward the new star of non-greed.
1 - Clarity / arising & passing
Immediately after the destabilisation of an L4 prior you will experience an ‘arising and passing’ event, or a manic/hypomanic phase.
This results in wild creativity, expansive ideas and the dunning-kruger effect. You mind is building a new model because the old one was dissatisfactory. It can come with some very extreme and prolonged altered states depending on how much learning was pruned.
The brain elevates phasic dopamine while in a state of high tonic dopamine in order to build new neural pathways.
Warning:
My own major clarity phases were orders of magnitude more intense than any combination of psychedelics I have tried. The 'big one' after the bodhitree protocol saw the construct of time dissolve, with 7 days feeling like approximately 7 years. I went through my own version of genesis, altering the laws of spacetime, entering the multiverse, and successfully removing all sorts of deep traumatic conditioning. At the same time, I remained a completely functional father and member of society: holding conversations, cooking dinner, and generally being a friendly person. It was when I was on my own that I went to the stars.
Make sure you have a supportive and understanding environment. This will keep you grounded if the deconditioning gets too much. Being around people and activities which you already have a playbook for will result in you coming back to the real-world and walking the old neural pathways.
The other world is where you can instigate change for your perceptual model, not this one. Just don't overdo it, and remember that the change is in you and you alone. Do not try to change the world; only try to change yourself.
2 - Doubt / dissolution
The brain then validates these pathways. Impostor syndrome, doubt, questioning.
The brain takes the old L3 concepts and tests them against the new L4 prototype. Some of them fit; some of them don’t. It is confusing and you revert to old behaviour and thought patterns as they are tested.
Many of the L3 layers no longer fit and are discarded (deconditioning) but some do and remain. The brain then oscillates between 1 and 2 until it finds relative parity.
This phase sees lower levels of both tonic and phasic dopamine. The brain lowers the water level so that it can test the existing irrigation system.
3 - Crisis / dark night
The brain then collects the false hypotheses and begins to deconstruct them. This is the dark night.
The initial construct which has been invalidated was built of many smaller constructs. The ones which were found to be inadequate are now being pruned through a process of dopaminergic destabilisation. Things which previously seemed obvious now fill you with fear, misery and disgust.
This is good - it is your brain identifying more redundant learning which will be removed. Once this learning is gone, your mind will be free to live in a more reality-aligned manner.
It might sound like a breeze, and it helps to know that this is actually part of the healing process, but this phase can be terrifying at times. I recommend reading the chapters about the dark night in MCTB2.
Dopamine levels here are low but spiky. Your brain is stress-testing the irrigation system with pulses of water. It is seeing where the weakness lie and breaking down unsuitable walls.
This is the calm after the storm. Your brain has isolated the next layer of constructs which need to be removed and is starting to purge them.
Dopaminergic tone will settle and the pulses will stop. The water level will begin to rise above the irrigation channels.
This phase washes away the walls which were broken during the dark night. It carries away the emotional detritus of maladaptive learning. You are free.
This will mean that thoughts are silken and can drift between concepts which were previously distressing without getting caught in existing grooves.
1 - Clarity / arising & passing
Your brain then goes into rebuild mode.
The L5 metacognition comes back into play and the direction that you take your mind during this phase shapes the channels which are carved.
Again, this presents as creative ideas, expansiveness and inspiration.
The insight cycle is merely an exaggerated version of how our brains function all day every day.
Eventually, once your brain has built L4 priors which align with the L5 metacognition, it will settle down and become a background hum. People who have weakened their priors enough times and to a deep enough level can do so multiple times in each meditation session, on demand. It becomes something you do intentionally in order to accelerate learning and adaptation to changing situations. Or just for fun.
The brain is ever plastic. If you change your L5 metacognition to seek another thing (eg. a reforming the mental health industry) then your brain will once again enter this cycle of deconstruction and reconstruction.
This is why it is of value to cultivate a scaffold and a second worldview, be it religion or art or fiction.
Over time, you can create a situation where your consensus-reality worldview and your scaffold worldview complement each other rather than contradict each other.
This is why some people can operate at a high level in a demanding world whilst also retaining their love of God, their Dhamma, and their ability to heal from events which would be traumatising to many.
Over time you can reach a point where your L5 metacognition is supported by both the trees, and there is no internal conflict despite having two discrete models for viewing the world.