Watch the Improvising Tools pt. 1 online guitar lesson by Brad Carlton from Guitar Lab: Latin Rock Lead
The two scales that you are using over the E minor and the B7 chords are E Aeolian and B Phrygian dominant. There are six common tones between these two scales because the only change is the D natural moving to a D# to accommodate the B7. This lesson explores these six common tones as melodic tools. One of the important principles that will be presented in this lesson is the concept of tension moving to resolution.