I wish I could blame my bad dancing on a condition called beat deafness which was first documented only five years ago. Dave, I know you can relate. Oh it's bad... my poor wife (chuckle). Sadly, we can't blame our clumsiness on beat deafness because it's a type of musical brain disorder that's extremely rare. We can follow a beat; our limbs just don't cooperate.
Researchers identified a 26-year-old man who when listening to music, could not follow the beat at all. He loves music, sings on pitch, but has no rhythm. So, then what is rhythm? It consists of several temporal elements such as pattern, meter, and tempo. These different elements of rhythm have been mapped to shared as well as uniquely distributed neural systems by brain scans. So what seems like a simple task such as tapping your foot to a tune, is actually quite a complex and little understood process. It appears only humans can process meter, while other species may be able to process pattern, and perhaps tempo.
Studies have also determined that distinct and distributed neural systems are involved in sensing and processing other elements of music such as the melody, harmonies and timbre. But our neural processing of rhythm is only the beginning of a person's ability to dance to it. That involves orchestrated movements that start in the motor cortex, then travel down twenty million nerve fibers in the spinal cord to an arm, finger, or any precise body part telling it how to move. Is it any wonder then that some people are better dancers than others? Researchers plan to do further studies on the young man to find the genetic basis for his beat deafness.