Watch the Inversions & Areas of Activity online guitar lesson by Henry Johnson from Jazz Expressions

Here's an application of playing in the "areas of activity" for the major 7th, minor 7th, and dominant 7th inversions for G. These areas are great places to improvise, especially a great place to play the pentatonic scale. Give it a try.

You might be wondering, "Why do I need to play in any given shape? Why am I playing in a high shape or a low shape? What determines that?" For me, I've been playing with piano players and keyboard players all my life, and when playing in the band, you have to interact with them. So, if I'm playing with a keyboard player who's playing high, I want to be playing low. You want to play the shape that makes the most sense so that you're not in the same register that they are. And if you do this for a long time, it will start to happen automatically.