Illusions and the Visual Cortex
The above image is not moving. It is an illusion created by
The illusion is created by how your eyes process and relay information to your primary visual cortex. Don't stare too awful long as it makes some folks queasy.
We, in a sense, create audio illusions with nature sounds to ease the human brain into deep relaxation and sleep. Our main concern however, is not the Primary Visual Cortex but the Secondary Visual Cortex (or cortices). This is the section of our brain that functions during visualization and dreaming. This is not theory but a scientific fact. One of the first things our brains do upon entering deep sleep is begin dreaming, so by stimulating the the Secondary Visual Cortex, using audible visualization sequences, our soundscapes act as a bridge from Alpha (relaxed) to the Theta (daydream) to Delta (deep sleep) brainwave states. By combining simple visualization with calming nature and natural sound the relaxation, meditation and sleep experience can be greatly enhanced.
So, what does an optical illusion have to do with creating virtually real audio environments? Not much, really. I just thought it was kind of cool.
Anyway, I better wrap up as I am getting seasick!