The uptempo record "MDNA" sees Madonna continue her love affair with dance music in an album dedicated to club-friendly tracks.

And Madonna has lost none of her ability to push boundaries, just as she did 25 years ago with themes of sexuality and youth rebellion.

The title, "MDNA" -- an allusion to the drug MDMA or ecstasy -- has caused a stir, while the music video for the second single, "Girl Gone Wild", has been slapped with an age restriction after YouTube deemed it too raunchy for under 18 year-olds.

The video, shot in black and white, sees the singer writhing and grinding with scantily dressed men, in a style similar to her "Erotica" days, when the video for her song "Justify My Love," was banned by MTV in 1990.

Madonna has said that the title meaning of her 12th studio album is threefold -- a reduction of her name, an abbreviation for "Madonna DNA," and a reference to ecstasy and the euphoria often experienced by its users.

But some music critics haven't exactly been blown away despite Madonna recruiting a bevy of top dance music producers, including house music DJ Benny Benassi, electro-pop duo LMFAO and her Grammy-winning "Ray of Light" album producer William Orbit.

Randall Roberts of the Los Angeles Times gave the album two out of four stars, saying it doesn't "offer much in the way of innovation," and that the iconic singer had "fallen behind...she is no longer setting the conversation in a genre she essentially invented."

The songs are tied together with hard bass beats and electro-synth tunes in uptempo dance songs like "Gang Bang" and "Girl Gone Wild," where the matriarch of modern pop music sings lyrics like "I know good girls don't misbehave, misbehave, but I'm a bad girl anyway."

"Falling Free" is one of the few tracks that change pace from the album's dance-core theme, described by Billboard's Keith Caulfield as a "gorgeous ballad." The Golden Globe-winning song "Masterpiece," from the soundtrack of Madonna's film "W.E." also stood out with its delicate acoustic guitar melody.

The singer doesn't shy away from her personal life, with lyrics such as "I tried to be your wife, diminish myself, and swallowed my life," in "I Don't Give A," featuring rapper Nicki Minaj, seen as an allusion to her former marriage with British director Guy Ritchie.

Billboard's Keith Caulfield called the album "a collection of thoroughly pumping pop tunes, some of which are slices of sheer brilliance," praising tracks such as "Gang Bang."

Alexis Petridis of British newspaper The Guardian, gave the album three out of five stars, calling it "business as usual" for the pop star.

Petridis added; "What's striking isn't that Madonna is still with us...so much as where she still is: a commanding presence at the absolute center of pop, as capricious and changeable a genre as music has to offer."

But Nitsuh Abebe of New York Magazine said "a lot of the music here feels hollow and strained...There is much expensive workmanship and machine-tooling around here, but not much...Madonna."

(Reporting By Piya Sinha-Roy; Editing by Jill Serjeant)

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