NEW YORK No one wants to think about retirement planning, and this MassMutual campaign from Mullen makes that notion about as literal and uncomplicated as you can get. Thought bubbles appear inside the minds of future MassMutual customers and jockey for front-of-mind position. (Woody Allen did something similar with white-capped-and-body-suited spermatozoa in one of his '70s films.) This spot is the funniest of the bunch, and the simplest. The guys in the front of the brain (all versions of actor Arnell Powell) are surprised to see "Retirement Planning" show up, and they suggest these possible responses: "I'm cold," "I'm hungry" and "What's on TV?" RP brightens when he meets "What's on TV Guy," as he's plopped in a lounge chair behind a big old-fashioned set. The spot bids consumers to, "Move MassMutual to the front of your mind." It really doesn't promise to simplify retirement planning or annuity shopping, but it makes results seem more achievable than spots showing fiftysomething people in floppy hats meeting with their architects on the beach.