Watch the Hybrid Picking online guitar lesson by Dave Celentano from Classical Concepts for Rock Guitar
Concept 2 develops hybrid picking, which is the combination of pick and finger(s) to pluck the strings. The most popular approach is to use a pick and middle finger combination, but on the video I use pick and ring finger. When the notes involved are on adjacent strings the pick/middle fingers might feel more appropriate, where as notes that are separated by several strings might be better approached with the pick/ring finger. Please experiment with these two variations and find one that works best for you. Check out the sequences of fours descending through the D minor pentatonic scale in Concept 2. Also notice that the pick only plays down strokes and the finger plucks only up strokes.