For years, there have been the Beach Boys, and there has been Brian Wilson, and the two rarely intersected. The pioneering Southern California group was so influential to pop that it was, and still is, widely regarded as America’s answer to the Beatles. But Wilson’s involvement with the band waxed and waned over the decades, and more recently his role has been nonexistent while he resurrected such long-delayed projects as “Smile” and a solo album, “That Lucky Old Sun.” Until now. The band, which continued to tour and record as the Beach Boys for decades, confirmed speculation that all surviving members of the mid-’60s lineup — Mike Love, Al Jardine, Bruce Johnston and David Marks — will reunite with Wilson for the band’s 50th anniversary with a world tour and a new album on Capitol Records in 2012. The band, which formed in Hawthorne, Calif., in 1961, rose to national prominence as the embodiment of an optimistic, youth-centric surf culture with singles including “Surfin’ Safari” and “I Get Around.” But by the middle of the decade, Brian Wilson had ceased touring, preferring to produce, write and arrange for the group (which famously arrived home from tour to find the group’s experimental 1966 masterpiece, “Pet Sounds,” essentially completed save for their vocals). This, coupled with Wilson’s use of psychedelic drugs and well-documented struggles with mental illness, led to a schism in the band that crested during the “Smile” sessions. A truncated version of the sessions, “Smiley Smile,” was released in 1967 to poor reception. Carl Wilson died of cancer in 1998, and Dennis Wilson died in a drowning accident in 1983. The surviving members of the group appeared together to celebrate the 40th anniversary of “Pet Sounds” in 2006.