This shallow acoustic representation of oneiric is deliberately used to show Ryans striving to connect the puzzle pieces together in his head. The case of stunning revelation in The Witness required a very deep oneiric mood, while for the scattered flashback in Patriot Games demanded the use of shallow oneiricism. Sometimes, like in The Fugitive, USA (1993) by Andrew Davis, flashback scenes are nothing but glimpses in which to accomplish any sense of aural oneiricism, distorted visual images are being accompanied by acoustically transformed and heavily manipulated meta-diegetic sound effects.
via Mladen Milicevic – Film Sound Beyond Reality.
Balasz also stressed that “asynchronous sound has no need to be natural. Its effect is symbolic and it is linked with the visuals it accompanies through its significance, in the sphere of mind, not of reality.” Balasz was convinced that “this is the richest and deepest possibility of artistic expression of sound film,” because the action can move on two parallel levels at the same time, “in the sphere of sound and in the sphere of visual image.”12 Mary Ann Doane stressed the difference between the voice-over and the interior monologue. She emphasized that interior monologue displays what is inaccessible to the image, what exceeds the visible: the “inner life” of the character.13