I recommend this book: Ajahn Brahm: The Jhanas; where a description of each form jhana & each formless sphere should be summarised, somewhere. Ajahn Brahm's description of vitakka & vicara as the "Jhana Wobble" is very helpful for discerning the difference between true jhana and the fake jhana often declared on Buddhist chatsites by shameless egotists.
In the sphere of infinite consciousness, the mind perceives infinite consciousness as the salient/ primary experience of the meditation. Also, the physical body continues to exist, even though the physical body is not experienced. Therefore, in the sphere of infinite consciousness, the other aggregates, such as perception, feeling & physicality (plus the subtle intention to remain in that meditation experience), continue to exist & dependently support consciousness.
Related to this, MN 43 describes the 9th stage called "cessation of perception & feeling". Here, consciousness ceases to operate because there is no perception, no feeling or any other sense object to support the maintenance of consciousness. However, note, the life force of the physical body continues to remain alive.
In the suttas, each jhana & sphere is described with the salient/primary experiences of that jhana & sphere; even though other phenomena may be experienced or may be functioning. MN 111 is a sutta offering a more detailed description of each jhana & sphere.
Reply to comments:
Each consecutive jhana & sphere represents a refining of the mind and the objects in the mind.
The feelings of rapture, happiness & equanimity of the four jhanas are based on bodily feelings arising in the physical body that has been profoundly relaxed & purified (even though the body itself, including the subtle breathing, is not experienced in jhana). This is probably why the four jhanas are called "rupa (form, material) jhana".
In the arupa spheres, only mental feelings & mental phenomena are experienced. However, as said, each arupa jhana is a refinement of the salient object perceived/experienced. Thus, in the sphere of infinite consciousness, the mind perceives or classifies that experience as 'infinite consciousness'. But as the mind continues to refine, that PERCEPTION "INFINITE CONSCIOUSNESS" ceases. Since there is no salient object left to PERCEIVE, the mind perceives "there is nothing". Then when this PERCEPTION "there is nothing" also ceases, the perceptual framework of the mind starts to breakdown before entirely ceasing. This breaking down of perception, where something akin to perception is occurring & non-occurring is the sphere of neither-perception nor non-perception.
What is important to understand here is perception & its dependent objects are refining, becoming more & more subtle, until there are no more objects to perceive. When there are no objects to perceive, perception & consciousness must cease (even though the physical body remains alive, as described in MN 43).
From Ajahn Brahm:
THE MIND-BASE OF UN-LIMITED CONSCIOUSNESS
Within the perception of unlimited space lies the perception of
no-space, of space losing its meaning. When the mind attends to this
feature within the First Immaterial Attainment, space disappears and
is replaced by perception of absolute one-pointedness of
consciousness. As indicated above by the common experience of
one-pointedness of time, in the state that perceives one-pointedness
of consciousness, consciousness simultaneously feels infinite and
empty, immeasurable and undefined. One has entered the second
Immaterial Attainment of the mind-base of unlimited consciousness.
This is the perception that fills the mind completely and persists
without wavering for even longer periods of time.
THE MIND-BASE OF NOTHINGNESS
Within the perception of unlimited consciousness lies the perception
of no-consciousness, of consciousness now losing it meaning as well.
When the mind focuses on this feature within the Second Immaterial
Attainment, all perception of consciousness disappears. Perceptions of
material form and space have already disappeared, and so all that one
is left with is the one-pointedness of nothingness. One has entered
the Third Immaterial Attainment of the mind-base of nothingness. This
is the concept that fills the mind totally, persisting unchanging for
yet longer periods of time.
THE MIND-BASE OF NEITHER PERCEPTION NOR NON-PERCEPTION
Within the perception of nothingness lies the perception of not even
nothing! If the mind is subtle enough to see this feature" then the
perception of nothingness disappears and is replaced by the perception
of neither perception nor no perception. All that one can say about
this Fourth Immaterial Attainment is that it is, in fact, a perception
(AN 9's, 42). In the simile of the thousand petalled lotus, this state
is represented by the 1,000th layer of petals, still dosed, with all
the 999 other layers of petals fully open. The l000th petal is almost
a non-petal, being the most subtle and sublime of all. For it clasps
within its gossamer fabric the famous "Jewel in the heart of the
Note: Ajahn Brahm's idea about Nibbana often appear questionable.