I want to know the answer to the following question:
What showed that memory exists even before that memory is known to the person?
All the background I'm provided with is that "Some neuroscientists and psychologists mistakenly equate the concept of engram and memory, broadly conceiving all persisting after-effects of experiences as memory; others argue against this notion that memory does not exist until it is revealed in behavior or thought (Moscovitch 2007).". Is that enough to answer the question?
Answer: yes