A difficult one to study but I think someone should study how dream symbols are infectious- that is, when people know one another, the dream symbol will appear in the other person's shared dream, almost as if the two psyches are having a conversation with one another.
A dreamer will unknowingly adopt the interpreter's own symbols knowing that they will be then better understood by the other person. Then they will keep repeating the symbol in various forms until the interpreter speaks the meaning of the symbol to them, bringing it to consciousness. And then the meaning becomes ridiculously obvious to both.
Sometimes the process can start even before the two people have met.
Seems apt in these times of global pandemic to study how symbols spread unconsciously in the hope of better mutual understanding.
Have you ever experienced anything like that?