Yes, it's Grateful Dead drummer Mickey Hart, in his 1961 senior yearbook picture from Lawrence High School, on Long Island in New York. As one of the band's two drummers (along with Bill Kreutzmann), Hart was one half of the Dead's original "Rhythm Devils" -- a name which he and Kreutzmann also briefly revived as a post-Dead touring band.

The one constant in Hart's post-Grateful Dead work has been his fascination with different ethnic and musical cultures from around the world -- particularly when it comes to percussion. Projects like 1991's 'Planet Drum' (which received the first-ever Grammy Award for Best World Music Album) have also earned Hart a well-earned distinction as an "ethno-musicologist." He has written four books on the subject, and is a member on the Board of Trustees of the American Folklife Center at the Library of Congress.

Nearly five decades after he first blew our minds with the Grateful Dead, Mickey Hart is also still very much in the business of consciousness expansion through music. On his most recent album with the Mickey Hart Band, ('Superorganism,' released on August 13, 2013), Hart taps into his own brainwaves (via a skull-cap he wore during the sessions), in an attempt to discover the relationship between human biology and rhythm.

Far out, man. Catch up on all of Mickey Hart's latest journeys into mind and music at his official website.

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