Before Nirvana's NEVERMIND closed out the year with the unexpected commercial triumph of grunge rock, R.E.M.'s OUT OF TIME was the sound of alternative music circa 1991. The smash singles " Losing My Religion"--perhaps the only Top Five US single ever to feature the mandolin as its lead instrument--and " Shiny Happy People" were the commercial face of the album. Elsewhere, however, R.E.M. makes a point of moving away from expectations, resulting in intriguing experiments like the surprisingly funk