Nur Alam Graphics/shutterstock.com Freestyle rapper, producer, and drummer Harry Mack is  still going strong , and millions of viewers continue to be utterly amazed at his mind-blowing talent. If you don't already know him, he's the guy who solicits random words from audience members and creates some of the best spontaneous rap lyrics of all time. His genius-level skill has not only attracted billions of views across social media, but has also attracted the interest of neuroscientists who have created reaction videos to help us all understand how Harry Mack accomplishes his seemingly impossible, brilliant performances. Dr. Anna Nordvig, a board-certified neurologist who runs the YouTube channel " Neurogal MD ," which focuses on neuroscience, brain health, and the connections between music and the brain, discusses Mack's work in  this reaction video . In it, she addresses how freestylers like Harry Mack and other improvisational artists can spontaneously generate artistic content.…