In defence of noise

So the real reason I am in Switzerland, besides of course to consume copious amounts of cheese and chocolate, is to do some research. And one of the projects I’m involved with is on the use of a technique called stochastic resonance to improve signal detection in Computer Tomography (CT) images. It’s an oxymoronic term at best, because stochastic means random, and resonance implies underlying structure and pattern. So, in short, I’m looking to see if adding chaotic order or orderly chaos to a CT image improves the ability of a radiologist to detect aberrations.

It doesn’t seem right – how can adding noise to a system make it somehow clearer? Improve it? And actually, it turns out that by every quantitative parameter of image quality, there is really not an improvement. It’s all in the visual perception. So even though quantitatively we may not have improved image quality by adding noise, the human visual system is better at discerning aberrations in noisy images than in clean ones. That’s amazing! Our brains like things a little messy, at least when it comes to vision (and, as it turns out, also sound).

Of course there is a small caveat and that has to do with the amount of noise you add – too much and you’ve lost the picture, too little and you’re not going to see resonance. Wouldn’t it be lovely to extrapolate this idea to life? Add a little chaos and underlying patterns become clearer. Maybe that’s why my daughter likes her room so messy – so she can find stuff in it! Maybe that’s why my son likes to dump out his Legos in one gigantic pile on the floor before starting construction.

StochasticResonanceSo here’s to living life amidst the cacophony, because adding a little noise to the system reveals it’s beauty in ways that a perfectly noise-free life just cannot do.

Note: One of my favorite day dreams is that I’m drummer for a rock band and when I was reading papers on stochastic resonance I immediately thought it would make a GREAT name for a band – unfortunately I have been beaten! So here is one of their tracks – it’s strangely hypnotic – enjoy!


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