Speech Impediment to Great Singing on American Idol

During January 2013 auditions of Season 12 of American Idol, there was Lazaro Arbos who has a terrible stutter when he talks, but sings beautifully. A week later, we encountered Micah Johnson who also suffers from a speech impediment, but rather than a stutter, it was due to "nerve damage" sustained during a tonsillectomy. (Watch videos below)

With stuttering, the problem mainly lies at the brain level. The brain coordinates how a person uses all of their throat muscles to create speech. Talking and language is mainly a LEFT-brain activity (or more precisely, the dominant hemisphere). Singing is mainly a RIGHT-brain activity and as such, uses different pathways than talking. It's also the same reason why patients who have suffered from a stroke may not be able to talk at all, but can sing their words out.

Now, in the case for Micah Johnson, it is reported that his speech impediment was due to "nerve damage" from tonsil removal surgery. As such, his speech impediment is NOT at the brain level (also known as central), but peripheral. Peripheral nerve injury is much more difficult to correct and requires extensive practice (speech therapy) in order to create brand new pathways at the brain level to help it "adapt" and compensate for the loss of function from the nerve injury. The analogy would be walking with a limp to compensate for a leg injury.

However, in Micah's case, it is a bit difficult to explain why he talks with an impediment, but sings wonderfully. It is not a matter of activating previously established brain pathways as what happens with stuttering.

With a tonsillectomy, there is a mouth gag placed to move the tongue out of the way. Typically, this surgery takes about 15 minutes to perform on average. Per Micah, his tonsillectomy took 90 minutes or almost 6 times longer than normal.

I hypothesize that the mouth gag over that time duration slowly crushed the nerve innervating the tongue (cranial nerve 12) causing it to not move as well leading to his speech difficulties. This complication is EXTREMELY rare and if it occurs, almost always temporary. This situation is analogous to a "dead" arm when sleeping on it for too long... but recovering normal function after a few minutes.

Unfortunately in Micah's case, it seems to never have recovered fully.

The puzzling issue for me is how is it that he is able to sing, but not talk well? Peripheral nerve injuries would affect ANY activity involving the affected muscle. For example, if the nerve to a leg muscle is cut, that muscle will not work well whether running or walking. The ability to sing, but not talk well due to a peripheral nerve injury is akin to stating that one can only limp when walking, but can run fantastic.

Anyone have any ideas what may be going on with Micah's amazing singing?

Just as an FYI, another rare complication of tonsillectomy that may lead to speech problems is velopharyngeal insufficiency leading to a hyper-nasal sounding speech. In this situation, there is no nerve damage present. Rather, it is an anatomic problem whereby the soft palate does not 'lift" completely to close off the nasal passage from the mouth. This problem can be surgically fixed.

In any case, best of luck to both men!