Watch the Rock Me: Ex. 2b online guitar lesson by Andy Aledort from Kings of Blues & Rock Vol. 4: B.B. King
Here's another solo pass over the "Rock me Baby"-type groove, and in this example I begin with a pickup into the 12-bar form, once again sounding a root note, C, on the high E string, followed by a quick slide up to the same C note fretted on the B string at the 13th fret. This positional shift affords a nice stinging vibrato on the root note that falls right on beat one of the start of the form. This maneuver also sets up the subsequent series of riffs that are played higher on the fretboard.
This solo also makes use of ascending chromaticism, found at the end of bar 4 with the use of a 4:3 ratio (four notes divided evenly over three eighth-notes in 12/8).