I was recently reading Reynolds Humphries book Fritz Lang, a study of the German director's American period films. While I find Humphries' approach too psychoanalytical for my liking - no surprise really, considering that it is an English translation of a thesis produced under the supervision of none other than Christian Metz in the 1970s - there are some useful summary descriptions and insights in there:
“[I]n the Langian textual system [...] all manifestations of vision and representation are bound up with questions of relativity and truth. Things may never be what they seem, but this tends to be elided in a desperate striving to pass belief off as knowledge in an attempt to maintain the ego as the center of a fixed network of concepts whose ideological nature is patent.”
“The Langian textual system is concerned first and foremost with the spec(tac)ular nature of the image and how we see it. [...] [T]his theme is often inscribed into the diegesis via the search of an investigator who believes that knowledge is a question of clear vision but who fails to understand that such vision is a matter not just of seeing things as they are but of grasping one's place in a discourse as subject of desire, of the unconscious.”
Substitute Lang for Argento and it seems to me you also have pretty good descriptions of the “textual systems” of The Bird with the Crystal Plumage, Four Flies on Grey Velvet, Deep Red and Tenebre.
Plus Ministry of Fear has both a seance sequence and a character named Neale...