Superposition of waves

In order to erase a standing wave you need to use another wave of the same amplitude and wavelength, but with a phase shift of π. Pictures and words in our brain are standing superposition of waves. Just like a Fourier transform of an image. Some of these images reside in our visual cortex connected to the environment by the visual nerves that transmit the images away and from our brain captured in our eyes. In order to decouple an image from the visual cortex one has to treat it with waves of opposing phase.