America is a lot closer to getting its own Radiohead, and it isn’t Wilco. My Morning Jacket, from Louisville, Kentucky, have been on the road to their OK Computer for a while; imagine “My Iron Lung” soaked in sour mash and you’re pretty close to the massed-guitar seizures on 2003’s It Still Moves. The band still has too much bluegrass in its blood and Lynyrd Skynyrd in the riffing here — the jamming elbowroom of “Lay Low” and the plunging power chords of “Gideon” — to pass for paranoid androids. But a major lineup change on the way to Z apparently inspired My Morning Jacket’s prime mover, singer-guitarist-songwriter Jim James, to mess with his template, to impressive effect. He is now writing actual pop songs, like the two and a half minutes of “What a Wonderful Man,” which jumps and crackles like a Seventies Dixie-rock take on the Who’s “Happy Jack.” And there is an emphasis on keyboards, in pulse and architecture, that adds buoyancy and color to James’ writing and flatters his keening, stratospheric tenor. The Eno-esque flutter and gentle bump of the electronics in “Wordless Chorus” bloom, with the addition of some tick-tock guitar, into something like Mercury Rev on Soul Train. In “Off the Record,” the band’s loose, rough strut dissolves into reggae-dub shadows, while the closing “Dondante” builds, explodes and expires like Pink Floyd’s “Careful With That Axe, Eugene”: It’s a long, riveting psychedelic death scene. Except James, as a lyricist, for all of his free-associative spray, is plainly focused on life and how to hold on to it. “Tell me, spirit — what has not been done?/I’ll rush out and do it,” he declares in “Wordless Chorus” — a lot like Radiohead’s Thom Yorke, but with more light in that near-falsetto.