what I find helps when I've hit a streak like that, it to repeat to myself, one frame at time, and really slow up every aspect of my pre-shot ritual. A little longer getting the ball comfortable in the hand, double checking my positioning on the approach, and double visualizing the shot.
Basically, it's totally clearing the mind, focusing on that shot only as if it's the first frame of a game. Nothing before it matters, and nothing after does either because if you screw up the first, you can still easily shoot a nice score.
Of course, I have another friend to starts to chant ten pin and it seems to allowing him to foucs better.