New Orleans is a music town. Pausing near a stairwell where an old man sawed feverishly on his fiddle the way Tchaikovsky taught him, I asked myself why I was so enthralled. Stepping aside for a passing parade of tubas, everyone did so with a smile because music made them happy. Peeking over shoulders, I came across reggae done well with different sized trash cans, and the giant "why?" kept up its rhythmic chant.

I wasn't concerned with the "what" of music, lord knows we have books and talking heads teaching us what music is. We have even more instructing us how to make music. What struck me was the variety and the universality. Crowds speaking every possible language tapped their toes to the same beat, and I had to know why.

As much as I sometimes dance with Puff, he does it for a biscuit, not the music appreciation. We say birds sing, yet we know for them it is just a way to say, "I'm horny". As much as many of our songs serve the same purpose, that is a recent application. Unlike animals, we enjoy the music itself, dare I say, even need it.

Yet pleasure for all creatures is tied to survival, some evolved stimulus like eating or procreating. Why did we evolve music as this pleasurable experience so unique to our species? It goes way beyond language and sending signals, which have clear purpose for us and animals down to crickets.

Wandering Bourbon Street, cogitating the recurring "why" without resolution, I was struck by the calming effect of the music I passed, how each street performer reset the pounding "why" in my head and replaced it with a refreshing pause. Continuing to shuffle along between musical interludes, I went back to thinking, sometimes exploring fresh paths due to the musical interruptions.

That's when the light started flickering, glowing brighter as the pieces started to fit together. The pieces came from a field of computers called parallel processing, and so I'd like to present a hypothesis.

A bit of geeky background. A pocket calculator can add a column of numbers far faster than we can, yet we can recognize a coffee cup faster than a roomful of supercomputers. How do we do this with wetware (neurons, axons, synapses, et al) that run individually so much slower than semiconductors? We do this by parceling out the task, by delegating parts of the job to different parts of our brain. Not just one part to recognize the shape and another the color pattern, but to thousands or even millions of little processors each trundling along on their tiny assignment while the supercomputer can do only one thing at a time.

Scientists are clear on the theory but parallel processing computers are primitive beasts compared to our wetware. The problem is that some controller or manager has to break work into tiny tasks, and then even harder, recombine the gazillion work products into a useful, cohesive solution. We know our brains are doing this because we can see the wiring between individual brain cells (neurons) being reconnected (axons, dendrites & synapses) as problems are worked. The wiring isn't physically rerouted as much as switches are thrown as to which wire to use. This spaghetti bowl of wiring connections goes far past adjacent brain cells and grows more complex the longer we work the problem.

Something has to return the system to its clean starting position after hours of pondering, much as football players must return to the scrimmage line after each play. Sleep is the obvious answer, but a coffee break or walk around the block can do the trick -- as can strapping on the mp3 earbuds.

Consider the rhythm and flow of sounds passing through your brain like a comb through tangled hair. Without all my explanation and conjectures, we know we return to our work with minds refreshed and somehow invigorated.

This is particularly true when we're stuck with a thorny problem defying solution. We realize banging our head against a wall is going nowhere because the synapses et al are as snarled as they can get. We need to unwind them, reduce pathways as short as possible, and try again. This can be done in as little as 3 minutes, coincidentally the length of most songs.

Then we have background music to help folks like me think. Without it, my brain isn't content to work its assignment. It flutters around, jumping at chances to think other thoughts. Like a bored child, it wanders off to analyze a stray sound. It has too much bandwidth and needs to be throttled down. Music reduces some of that bandwidth by taking synapses out of the jumble, smoothing them out for their next project.

We have no idea how music resets our parallel processor any more than how its controller manages its delegation, but we can assume its waves and harmonics pours through our entire brain. That is why we can enjoy the effect of only one song at a time. Two songs at once would be like two combs crossing paths.

That is also why hearing the same song over and over gets annoying, even when we liked the song the first time. Pushing the same reset button over and over is like combing in the same direction; after a while, your hair is as straight as it's going to get, and it becomes irritating. Time for another song and to comb in a different direction.

Whereas all animals can think, none of them can think as elaborately as us. None of them need a reset button. This is why I admire musicians. Without them, our unique and magnificent gift to think would be so much less useful.

If music has this calming effect to reset our parallel processor, I wonder if there is a visual equivalent. Perhaps an artist can chime in.