avijja is a mental element, has to do with that which is called mind, consciousness or intellect.
that which is called mind, consciousness or intellect arises as one thing and ceases as another and is implicated in contact.
when on has contact come into play, it isn't something that is thought to persist as the consciousness that is in the meeting of the three changes as it arises.
When we talk about a certain-consciousness being implicated in an instance of contact, that is consciousness 1 doing the meeting, as this changes as it arises it is associated with consequent consciousness 2 for a future and the preceding consciousness 0 for a past state.
Therefore Nama doesn't include vinnana but only that which is contact and born of contact on one end and the form implicated in contact on the other end, consciousness is in the middle and is associated with both as to that meeting of the three which is included in name as 'contact'.
It is said that the past is one end, future the other end and present in the middle.
It is also said that form is one end, name the other end and consciousness is in the middle.
If the two statements are superimposed then one would say that the past has form on one end, name on the other end and consciousness in the middle. That the present has form on one end... consciousness in the middle. That the future has form on one end... consciousness in the middle.
That is because contact has no temporal persistence as elements change as they arise.
It is also said “Contact, reverends, is one end. The origin of contact is the second end. The cessation of contact is the middle.
If one was to superimpose this on the first statement it would be: The past has contact on one end, the origin of contact on the other end and cessation of contact in the middle. The present... The future... cessation of contact in the middle.
“Monks, there are these three topics for discussion. Which three?
“One may talk about the past, saying, ‘Thus it was in the past.’ One may talk about the future, saying, ‘Thus it will be in the future.’ Or one may talk about now in the present, saying, ‘Thus it is now in the present.’ https://www.dhammatalks.org/suttas/AN/AN3_68.html
“Bhikkhus, there are these three pathways of language, pathways of
designation, pathways of description, that are unmixed, that were
never mixed, that are not being mixed, that will not be mixed, that
are not rejected by wise ascetics and brahmins. What three?
“Whatever form, bhikkhus, has passed, ceased, changed: the term,
label, and description ‘was’ applies to it, not the term ‘is’ or the
term ‘will be.’
“Whatever feeling … Whatever perception … Whatever volitional
formations … Whatever consciousness has passed, ceased, changed: the
term, label, and description ‘was’ applies to it, not the term ‘is’ or
the term ‘will be.’
“Whatever form, bhikkhus, has not been born, has not become manifest:
the term, label, and description ‘will be’ applies to it, not the term
‘is’ or the term ‘was.’
“Whatever feeling … Whatever perception … Whatever volitional
formations … Whatever consciousness has not been born, has not become
manifest: the term, label, and description ‘will be’ applies to it,
not the term ‘is’ or the term ‘was.’
“Whatever form, bhikkhus, has been born, has become manifest: the
term, label, and description ‘is’ applies to it, not the term ‘was’ or
the term ‘will be.’
“Whatever feeling … Whatever perception … Whatever volitional
formations … Whatever consciousness has been born, has become
manifest: the term, label, and description ‘is’ applies to it, not the
term ‘was’ or the term ‘will be.’
“These, bhikkhus, are the three pathways of language, pathways of
designation, pathways of description, that are unmixed, that were
never mixed, that are not being mixed, that will not be mixed, that
are not rejected by wise ascetics and brahmins. http://buddhadust.net/dhamma-vinaya/wp/sn/03_kv/sn03.22.062.bodh.wp.htm
“The past, reverends, is one end. The future is the second end. The
present is the middle. And craving is the seamstress …
“Contact, reverends, is one end. The origin of contact is the second
end. The cessation of contact is the middle. And craving is the
seamstress... https://suttacentral.net/an6.61/en/sujato
what's called 'mind,' 'intellect,' or 'consciousness' by day and by
night arises as one thing and ceases as another. Just as a monkey,
swinging through a forest wilderness, grabs a branch. Letting go of
it, it grabs another branch. Letting go of that, it grabs another one.
Letting go of that, it grabs another one. In the same way, what's
called 'mind,' 'intellect,' or 'consciousness' by day and by night
arises as one thing and ceases as another. https://www.accesstoinsight.org/tipitaka/sn/sn12/sn12.061.than.html
Consciousness is conjoined with perception & conception [genesis] because what one cognizes that one perceives and what one perceives that one conceives of.
Therefore Consciousness is conjoined with Sankhara.
Three aggregates are conjoined with consciousness. The aggregate of form is not conjoined with consciousness. The aggregate of consciousness should not be said to be, conjoined with consciousness or not conjoined with consciousness. Three aggregates are generated by consciousness. The aggregate of consciousness is not generated by consciousness. The aggregate of form sometimes is generated by consciousness; sometimes is not generated by consciousness. Three aggregates are co-existent with consciousness. The aggregate of consciousness is not co-existent with consciousness. The aggregate of form sometimes is co-existent with consciousness; sometimes is not co-existent with consciousness. https://suttacentral.net/vb1/en/thittila
One can say that the terms sankhara and consciousness are describing the same reality in different ways and can therefore not be separated beyond a delineation of difference.
The difference between Consciousness and Consciousness Aggregate is that Aggregated consciousness refers to classes of past, present & future consciousness and not one among them taken as a cause for another. In this sense the Aggregate Consciousness means plural consciousnesses whereas a particular consciousness is something one would think about as changing as it arises and thus associated with three ends.