n[I]ck[S] [P]roject: Sound and Manipulation

Even though we've only read an act of Othello so far, everyone can tell that Iago is a big jerk master of deception. Similarly, auditory illusions can fool even the greatest of us. Many of these illusions exist (enough to constitute a Wikipedia page?!) but I will only be covering the two coolest ones I found

Tritone paradox

This illusion occurs when you are presented with a series of two successive notes, and are told to decide whether the pattern is ascending or descending between each pair. Try it yourself! (and record your answers):

I hear: 1) ascending 2) ascending 3) ascending 4) descending. It's probably different for you.

This illusion works because each pair of tones actually diverges by an octave (same note, about a 12-year old's hand apart on the piano) and whichever tone you perceive is based wholly on your unique brain.

Shepard tone illusion

I've heard this illusion many times, but it never loses its wonder.

Whenever I listen, I get nervous as the pitch rises and rises, and I move to take off my earbuds before my ears explode. However, the moment never arrives and yet the pitch continues to rise. This illusion does consist of rising pitches, so we are somewhat sane. However, the trick (and what we don't perceive) is that whenever a pitch reaches a certain point, it drops backs down a couple octaves and restarts its endless cycle. This is similar to a barber pole that seems to rise up forever but never move an inch.