Quite simply, where does the term "word salad" come from? I've found it a very frustrating thing to try to do web searches on, as it typically gets munged into searching about the "word 'salad'".
The oldest reference I've found is in a Google Books hit from 1954 in which they refer to it being a common term of doctors (in psychiatry). My assumption is that this is the origin, but I'd be interested if there are any solid cites that can be found earlier than this one.