The original recording of the song, over ten minutes long, features little more than a spoken introduction and a much-praised extended guitar solo by Eddie Hazel. Music critic Greg Tate described the song as Funkadelic's A Love Supreme; the song is #60 on the Rolling Stone list of 100 Greatest Guitar Songs. Reportedly, "Maggot Brain" was Hazel's nickname. Other sources say the title is a reference to band leader George Clinton finding his brother's "decomposed dead body, skull cracked, in a Chicago apartment."Michael Hampton (Hazel's replacement as lead guitarist) recorded his own interpretation of the song live in 1978, which was included in a bonus vinyl EP that was distributed with the album One Nation Under a Groove; the cut is also included in most CD editions of that album.

According to legend, George Clinton, under the influence of LSD, told Eddie Hazel during the recording session to imagine he had been told his mother was dead, but then learned that it was not true. The result was the 10-minute guitar solo for which Hazel is most fondly remembered by many music critics and fans. Though several other musicians began the track playing, Clinton soon realized how powerful Hazel's solo was and faded them out so that the focus would be on Hazel's guitar. Critics have described the solo as "lengthy, mind-melting" and "an emotional apocalypse of sound."

The entire track was recorded in one take. The solo is mostly played in a pentatonic minor scale in the key of E minor over another guitar track of a simple arpeggio. Hazel's solo was played through a fuzzbox and a Crybaby Wah wah pedal; some sections of the song utilize a delay effect. This style would be revisited later in Standing on the Verge of Getting It On on the track "Good Thoughts, Bad Thoughts". A live version with full band accompaniment was released in 1997 on the album "Funkadelic Finest".

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Wikipedia