Erykah Badu, ''New Amerykah: Part One (4th World War)'' (Universal/Motown) On her fourth studio album, ''New Amerykah: Part One (4th World War),'' Erykah Badu moves even further away from the neo-soul conventions she helped usher in more than a decade ago.

Instead of re-treading the simple melodies and succinct, pop song structures from her 1997 debut, ''Baduizm,'' she has mined an increasingly looser approach with each subsequent release. ''Mama's Gun'' (2000) ends with a 10-minute suite, and ''Worldwide Underground'' (2003) is a moody, 50-minute EP full of rambling grooves and hazy lyrics. More than ever though, Badu challenges fans to keep up with her creative impulses. Those who do will be richly rewarded for their effort. The CD is more daring than the album's current single, ''Honey.'' Hidden as the disc's closing bonus track, it's almost an anomaly given the preceding material.

Dark, mesmerizing head-nodders largely produced by hip-hop eccentrics Madlib and Shafiq Husayn and Taz Arnold of Sa-Ra Creative Partners dominate ''New Amerykah.'' Incantatory chants, esoteric spoken-word rants and Badu's quirky vocals - whether achy blues or mumbled coos - add to the funky jumble.

Indeed, it's a brilliant mess where songs often switch tempo midstream then settle back on-track. Yet the disc is also where Badu's lefty socio-politics (''The Cell''), messages of self-acceptance (''Me'') and the power of perseverance (''Soldier'') reveal an artist willing to share herself as the unfinished article. On the hypnotic ''Master Teacher,'' she confesses: ''See, I've been in search of myself/ for it's just too hard for me to find ... cause I'm in the search of something new.'' This effort is certainly a huge step in the right direction.

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By BRETT JOHNSON For The Associated Press

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