But I'm a grump, I'm a weirdo

Dissatisfaction is the emotion on which Thom Yorke thrives.

This week, Thom Yorke releases his first solo album. This is a typically unpredictable move from someone forever at pains to follow no script but his own.

His band recently embarked upon a mini tour of Britain, showcasing up to six new songs and thereby suggesting their seventh album was imminent. Not so. These songs, Yorke has since explained, are merely works in progress, part of a teaser campaign, if you like, to sate impatient fans and to remind everyone else that Radiohead remain an ongoing concern.

But now Yorke is a solo artist. The album is called The Eraser and has been produced by longtime Radiohead collaborator Nigel Godrich. It features, in part, "bicycle wheels and a prosthetic arm" in lieu of regular instruments.

Yorke is adamant that this latest move not be misread. "As you know, the band are now touring and writing new stuff and getting to a good space," he posted on his website. "So I want no crap about me being a traitor and whatever, splitting up [the band], blah blah. This was all done with their blessing. And I don't wanna hear the word 'solo'. Doesn't sound right."

A peculiar thing to say given that The Eraser is clearly a solo record - but then that's Yorke for you: even his fansite missives sound grumpy. Still, what did we expect? The man is no more likely to mellow with age (he is now 37) than he is to commandeer a team of huskies and go trekking to the Arctic Circle.

Radiohead, of course, are the leading band of their generation, unwittingly responsible for many soundalikes (Coldplay, Keane, Snow Patrol, Athlete ... take your pick). The quintet formed in their native Oxford back in 1988, initially under the name of On A Friday.

By 1992, they had released The Drill EP, that established them as an uncommonly emotive guitar band that took inspiration from various quarters (The Pixies, REM, even Nirvana) while making a sound quite their own.

A year later came Creep, their signature tune, with its cranking guitar chords and plaintive refrain, "I wish I was special", which promptly elevated them into superstars for the abject and forlorn.

A hit everywhere, Radiohead suddenly became a global concern.

If Pablo Honey, their 1993 debut album, was more notable for its promise than its innovation, then 1995's The Bends made them Britain's leading guitar act.

Thom Yorke, formerly an affable, if awkward, young man had now become A Tortured Artist. His crooked teeth and lazy eye brought him condolences he didn't welcome and a cruel mockery he couldn't abide (Liam Gallagher once laughed at his "[expletive] cabbaged eye").

But rather than shy away from attention, he dyed his hair blonde, then shaved it off altogether. He took to scowling, not just with his face but every coiled inch of his five and a half foot (1.67m) frame.

The band's 1999 Meeting People Is Easy documentary suggests there are few things in life less satisfying than being in a successful group.

Creatively, though, Yorke was reaching the height of his powers. Alienation and millennial discontent had rarely sounded so thrillingly ornate as on 1997's OK Computer, and its breadth of imagination shamed the band's competitors, toiling with the old verse-chorus-verse approach. In its masterful opener, Airbag, Yorke sings: "I'm back to save the universe." Many agreed, and the album has been voted the best record of all time in innumerable magazine polls.

The four other members of Radiohead were, presumably, thrilled. This was what being in a band was all about: success, worship, the burgeoning of the bank balance. For Yorke, however, things started to go awry. It's clinical depression, said some; a midlife crisis come early, opined others. Whatever the reason, Yorke's cheerless world view seemed only to be compounded by his group's success.

Over the next five years, Radiohead would become an altogether different kind of band.

Fans - and, more pertinently, their record company - may well have wanted more of the same mesmerising and, ultimately, "commercial" music, but its frontman, naturally, had other ideas.

While it has never been officially acknowledged, so far as studio recordings went Yorke effectively rendered his band unemployed. For the next three albums, Kid A (2000), Amnesiac (2001) and Hail To The Thief (2003), the singer belligerently ploughed ever deeper into electronic music.

These were deliberately bewildering records, from which one could infer Yorke's bleakening mood. In spite of their anti-easy listening content, each reached number one in the British charts. Yorke was duly mortified but he had, perhaps mercifully, finally found a worthy vent for his ire.

He became a face for Oxfam's Make Trade Fair campaign, and took an active part in Friends of the Earth's The Big Ask, a crusade for a new law to force the government to cut carbon dioxide emissions. "We have to do something dramatic," he said recently. "There is no way climate change will be dealt with unless it's structural - as a law. We can't address the issue on a voluntary basis."

Why did he feel moved to lend his name to such a worthy cause? "You have a certain amount of credit you can cash in with your celebrity, and I'm cashing my chips in with this."

Recently, Friends of the Earth asked whether he would meet the British Prime Minister at Downing St. He declined, saying that Blair was a man with "no environmental credentials. I have no intention of being used by spin doctors to make it look like we make progress when it is just words.

"I don't want to get involved directly. It's poison. [So] I'll just shout my mouth off from the sidelines."

He also looks set to reignite controversy over the death of David Kelly after recording a track for The Eraser implying the scientist may have been murdered. An outspoken critic of the Iraq war, Yorke described the song as "the most angry I have ever written".

Harrowdown Hill is named after the place where Dr Kelly was found dead after being named as the source of a report that the Government had exaggerated the threat posed by the Iraq regime in the run-up to the war.

Last year, Radiohead severed ties with their record company after 13 years. Just as he takes issue with so much in life, Yorke also takes issue with conglomerate-owned labels who work their artists like Trojans to then reap the vast majority of the financial rewards.

Noel Gallagher once said that the path of the solo artist is "a very long road to loneliness". But life can't all be bad for Yorke. He is happily married, after all, to his university sweetheart Rachel, and is father to young Noah, 5, and Agnes, 2.

Those who have heard his imminent solo album have described it as "customarily brilliant", and reports from the Radiohead tour suggest the band still have creativity to burn. But then his curmudgeonly nature is surely the key to what makes Thom Yorke such a fascinating artist. If he were happier, it might be harder to tell the difference between him and James Blunt.

Dissatisfaction is the emotion on which he thrives, and thank goodness. The snarl suits him.

LOWDOWN

Who: Thom Yorke, Radiohead frontman, now flying solo.

Born: October 7 1968 in Oxford, England.

Releases: Pablo Honey (1993), The Bends (1995), OK Computer (1997), Kid A (2000), Amnesiac (2001), Hail to the Thief (2003), The Eraser (solo album, 2006). He has also collaborated with Bjork, P.J. Harvey, James Lavelle, Unkle and DJ Shadow.

Trivia: As a child, Yorke wrote his first song Mushroom Cloud about nuclear weapons.

- INDEPENDENT