The Shepard–Risset tone: tone that seems to continually ascend or descend in pitch, yet which ultimately gets no higher or lower
McGurk effect: the visual information a person gets from seeing a person speak changes the way they hear the sound
Deutsch’s scale illusion: two series of unconnected notes appear to combine into a single recognisable melody, when played simultaneously into the left and right ears of a listener.
Tritone Paradox: a sequentially played pair of Shepard tones separated by an interval of a tritone, or half octave, is heard as ascending by some people and as descending by others.