Some time in the late 1970s, I heard a lecture by a researcher at the Air Force Institute of Technology, who stated that if you took Fourier transforms of an optical illusion, and then reconstructed the image while progressively dropping the highest-frequency terms, the reconstructed image would eventually demonstrate the illusion.

This suggests that our sensory perceptions (and possibly, in the current research, our memories) lose fine detail in a way that can be analogized, if not explained directly, in terms of discarding or losing high-frequency information.