Much is made of the physical resemblance of the actresses; not extraordinarily so, but it was certainly a deliberate piece of casting by Bergman to choose both Bibi Andersson and Liv Ullman in these roles.
Much can be interpreted from Bergman’s use of interludes of clips from films, which some have cited as a Brechtian alienation technique. The film begins with several clips, which includes crucifixion, a dead sheep, a cartoon, a spider (which Bergman uses as a symbol to represent God elsewhere) and notably a boy whose mother’s face is projected, distorted, on a screen (which I’m sure is meant to be Elizabet’s son). In some school of psychological thought, these represent childhood images of trauma, but it also represents an indication of the fictional and artificial nature of the film on Bergman’s part.
Persona is certainly the kind of film you have to take at more than just face value. If you’re willing to invest time and thought, there’s so much to explore. It’s a remarkably deep and provocative account of a breakdown, filled with psychoanalytic insight. It’s clearly the work of a film maker at the peak of his powers, effortlessly outstripping his contemporaries time and again. And then there are the stunning performances of two outstanding actresses, which I’ve barely mentioned. Persona is one of the most striking and powerful films you could ever watch. Perfect.