It's amazing that intelligent people often accept material answers to immaterial questions like memory, consciousness and thought. As if those questions could ever be answered by natural sciences.
Given our species long history of pushing back the boundaries of mysticism, fear and uncertainty, it would seem presumptuous to doubt that our own minds are somehow exempt from the rules of the natural world.
It's pretty clear there is a physical basis for cognition. Some extremely pedantic philosophers may not come to the same conclusion though. If you have any doubts, here's how you can find out: get a friend to beat your head in with a baseball bat (made with preferably something tough like steel or titanium).