Sunday, November 11, 2007

Optical and audio illusions

The diagram on the right is a pretty common optical illusion (LINK TO IMAGE OWNER"S SITE) that very convincingly demonstrates that we perceive things in a way that is not strictly objective, or sometimes even remotely correct. So much parallel processing goes on to produce our visual perception that there has to be some shorthand somewhere. Most of the time the brain does OK but when faced with more difficult information, it sometimes fails terribly.

Such is the case with the image above: ALL of the lines are perfectly straight and rectilinear. There are no angles that are not right angles, and all the rows are columns are perfectly straight left to right, and up to down.

Music is not so "parallel", is it? We have two ears and the information is presented to us serially, for the most part. Right? Wrong. Music, unless presented as a single varying tone, is indeed a complex illusion. Chords and tones blend and are perceived in rather complex ways, which is why it is easier to listen to and understand when presented with a beat and some repetition. The beat gives the mind a chance to do its shorthand and the organization it provides permits attention to details without having to re-perceive that part of the music. The rhythm section is so important, moving the mind along through the course of the song. We are fortunate that our brains follow it well, as without it, much music would appear far too complicated to listen to without learning it after multiple listening. In jazz and classical music, there are plenty of examples of much more "challenging" music that does not depend on the well worn path of beat-driven simple structure, so multiple listening sessions and some active mental processing are needed to get comfortable enough to appreciate certain arrangements, such as Pharaoh's Dance by Miles Davis. If you know the Davis vernacular, you might get it on the first listen. Many readers here are jazz sophisticates. But for the average listener, it takes some practice to hear it. There are even fewer familiar elements in the work of Sun Ra, Ornette Coleman, or Edgar Vares. Twelve bar blues, disco beat, Sousa marches, and now even the math of Mozart, once learned over years of listening, still have illusion and the natural working of the human brain, to thank for their relatively easy continuity. Now that TV and all other media sources have so much musical content, everyone grows up with a rich musical vocabulary, and amazingly, they hardly know it. Great musicians and composers tap into this pre-knowledge and when they are successful, they hit that sweet spot of perception, and may even have a hit. At the very least, they have crafted the tones and rhythms already in our heads for the most part, creating the illusion of recognition. Many successful artists do it, and we like it!

Years ago I read Copeland's book "What to listen for in Music" or maybe it was "How to listen to music". He stole the magic from music and revealed how totally manipulative he and other composers are, and he wrote in such a condescending tone that I could not enjoy Copeland for years after. Once I was watching the Carson show and Miles was on, and he was such an ass, and it changed the way I heard Miles for a long time. Look at the image and enjoy it, it's fun to see the patterns and excites the eye and does a little visual dance for you. Its magic is still there, and it is nice to look at.

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