On a side note: I find a significant reduction in verbal skills after an extended period of coding. I don't think there are long term effects but it can be disconcerting when you basically forget how to speak. (Or is this just me?)

It may just be an effect of your coding techniques using the language centers of your brain. I have the same experience when playing a musical instrument or rhythm game, or when reading a book for an extended period of time. It's as if the language centers can focus on one sort of activity at a time. I find that after a few minutes I can switch back to verbal mode. Additionally, when I am focusing on a rhythm I am completely unable to speak. I can internally hear what I want to say, but I can't actually form the words. Friends of mine have great fun asking me questions while I'm playing rhythm-based video games. Usually the most I can respond with is a labored "yes!" or "no!", to humorous effect. Fortunately the behavior dissipates when I'm done playing :)

Interestingly, different people can use different portions of the brain for the same activity. A study was performed which measured the performance of participants as they spoke while marking time (holding a steady rhythmic beat). Some of the subjects had irregular beats while speaking, but others kept steady time. When asked how they were performing both activities at once, the unsteady ones said that they were marking time by internally verbally counting. The steady ones were internally visually watching numbers roll by. Both groups had the same performance when marking time while not required to speak.

The brain is a funny thing. They can vary greatly in the mechanics of how they accomplish a given task.