No bolt of lightning, no voice from the heavens, not even a lightbulb dangling overhead -- for years scientists have been searching for the source of creativity, having discarded the myths and memes of the past.

Now scientists at Northwestern have announced they've found the first physiological evidence of a connection between creative thinking and sensory distractions, or what they call "leaky attention."

In sound tests given to 97 subjects, the researchers found that poor sensory gating, the ability to filter unnecessary stimuli from the brain, correlated with a higher number of lifetime creative achievements.

Leaky attention "may help people integrate ideas that are outside the focus of attention into their current information processing, leading to creative thinking," the authors wrote in a study published in Neuropsychologia in January.

Noise, in other words, aids inspiration.

In order to test this noise factor, the subjects first filled out a lengthy questionnaire about their real-world creative achievements. Then they were hooked up to an EEG and presented with the sound of two clicks in rapid succession. Those whose response to the second click was equal or nearly equal to their response to the first, were considered to have leaky attention.

"Thus, the more creative achievements people reported, the leakier was their sensory gating," the report concluded.

One likely "leaky" genius from the past was German writer Johann Wolfgang von Goethe. Dogs barking in the street, the building of a bowling alley, even the movement of a weaver's loom -- all drove Goethe to distraction, and to complain to authorities. (One of his less famous lines from "Faust": "Be still, thou poodle; make not such racket and riot!")

Many geniuses, of course, have been known to play the role of rude narcissist when it comes to unwanted interruptions. Not so, Marcel Proust, who was profoundly polite even as he nagged, as he did in this letter, to an upstairs neighbor. “If your charming son, innocent of the noise that martyrizes me, is nearby, please give him my best wishes," Proust wrote in the letter, among dozens discovered just last year. (Proust later employed wax ear plugs and lined his bedroom with cork to counter the noisy distractions of Paris life.)

More than 180 years after Goethe and a century beyond Proust, neuroscientists seem to say these great complainers of the past didn't know how good they had it. Researchers now specialize in the science of creativity, and have found that blue computer screens improve performance on creative tasks and that moderate noise is more conducive to creativity than either a low-noise or high-noise environment. Call it the Goldilocks principle of creativity.

And for those who can't seem to find the right ambiance for inspiration? Just the right creative boost is only an app away.

Coffitivity, which can be downloaded on most smartphones, provides a "library" of sounds from various cafes, the favored hangout of many a budding young genius. So if your creative impulses are best managed via a laptop and a latte, then all that's left to do is cue the cacophony.