Hmmm, I believe I have first-hand experience with this. Often as I go about my day, I get sudden flashes of a scene recalled. It feels visceral and real - how I imagine electrodes stimulating the brain might bring forth feelings and memories. They're usually just scenes, with a strong feeling attached.

These "memories" aren't recalled from my life, often it would be impossible for them to be, and yet they feel like mine.

I imagine there's some medical explanation for this, but I've no desire to approach a doctor with such symptoms!