The New York Review of Books has a reflective piece by Oliver Sacks on the swirling mists of memory and how false recall has affected authors and artists throughout history.
[Science] is startling to realize that some of our most cherished memories may never have happened—or may have happened to someone else. I suspect that many of my enthusiasms and impulses, which seem entirely my own, have arisen from others’ suggestions, which have powerfully influenced me, consciously or unconsciously, and then been forgotten.
Similarly, while I often give lectures on similar topics, I can never remember, for better or worse, exactly what I said on previous occasions; nor can I bear to look through my earlier notes. Losing conscious memory of what I have said before, and having no text, I discover my themes afresh each time, and they often seem to me brand-new. This type of forgetting may be necessary for a creative or healthy cryptomnesia, one that allows old thoughts to be reassembled, retranscribed, recategorized, given new and fresh implications.
Sacks reflects on some of his own shift sans of memory and the thin line between ‘literary borrowing’ and unrecognised remembering.
Mind Hacks 
Ah, neat. I’ve been very intrigued by false memories since realizing a particular memory of mine could not have happened. That was an eerie feeling, to say the least.
It was an undramatic memory of reading an article by a specific writer, in a specific magazine while on a bus trip. I never questioned the memory until I tried to track down a copy of the article, which tuned out not to exist. The author’s photo I’d recalled seeing with the article turned out to be someone else entirely. The author I believed to have written the piece had written no such thing, and what’s more, a little digging showed that the information recalled from the article was only partly correct.
This could be attributed to dozing off and having a realistic dream, except that I was sure I’d bought the magazine at a certain shop…which turned out not to have been built until a year after this memory supposedly took place. I must have added things to this memory as time went on, never realizing it. The only thing that can be pinned down is the date of the bus trip, and that’s only because I rarely take a bus anywhere.
I would never have questioned the reality of this had I not gone looking for that article. How memories are created is a fascinating subject.