Well, yes and no.
I believe the writer means "ritual" in a literal sense, but the writer is considering the aspect of collective ritual.
The idea is that Freud thought about how dream-work affected people as individuals, but Susan Hiller thinks about how the "ritual" of dream-work affects groups of people, rather than just individuals.
So, ritual means ritual, but your question makes sense, because the sentence talks about viewing the ritual from different aspects.
Of course, it is always possible that I am wrong, haha!
Good luck!