What would be your reaction if your doctor asked you to play guitar while they performed surgery on your brain? It doesn’t sound quite appropriate. But that’s exactly what happened to Christian Nolen, a professional musician from Florida who was diagnosed with a brain tumor and underwent a craniotomy. Nolen’s tumor appeared on his right frontal lobe, a region in the brain that controls the movement of body parts on the left side. This part is also linked to a person’s speaking ability, language, and other cognitive functions. “I had lost feeling in my whole left side. From the waist up, like, …