When first generation rapper Doug E. Fresh, former Roots beatmaker Rahzel or "Yo Gabba Gabba" rapper Biz Markie learned to mimic a hip-hop rhythm using only their voices, chances were they had little idea what they were actually doing with their mouths.
"Beatboxing,” as it came to be known, includes laryngeal lowering and lingual retraction, labial approximation, velic raising (to seal the nasopharynx off from the oral vocal tract, of course) and rapid raising of the tongue dorsal.
All this time, these artists thought they were just making beats. A team of linguistics and engineering students at USC, however, wanted to learn more about the mechanics behind the rhythms. So by using MRI technology, they recorded an unnamed local beatboxer working his magic, broke down the most commonly employed sounds by examining the movements of his mouth and then analyzed the data.
The results were published in the fascinating if dauntingly titled paper “Paralinguistic Mechanisms of Production in Human ‘Beatboxing’: A Real-Time Magnetic Resonance Imaging Study,” which reveals the miraculous ways in which the human voice can be adapted to replicate synthetic sound. It's available for reading through the Acoustical Society of America's website.