Octave illusion: stimulation frequencies can modulate perception.

The octave illusion (Deutsch, 1974) is a well-known auditory illusion elicited by presenting a dichotic sequence of two tones separated by an octave during which the high and low tones alternate between both ears. This illusion engages an important mechanism of auditory perception, which is pitch perception. Previous studies used central frequencies of the useful musical spectrum to elicit the illusion.