Kristin Hersh first began to hear her own songs when she was 16, concussed in hospital after a "witch" in a car knocked her off her bicycle. But they didn't come to her, as they did in Paul McCartney's dreams, as gloriously melodic epics. In her memoir, Paradoxical Undressing, she calls the sound in her head a "metallic whining, like industrial noise… layered with humming tones and wind chimes".
And yet Hersh was able to tame these strange sounds into some of the most influential American rock music of the late 1980s. Her band, Throwing Muses, laid the groundwork for much of Nirvana's success in the way her stark, anguished material contained just enough of a pop sensibility to make sense.
Since then, Hersh has recorded 20 albums of material that she now gives away free, and is firmly fixed as something of an indie icon. But Paradoxical Undressing isn't some hoary old memoir full of tall tales of life on the road and rock excess. Instead, it's an intimate snapshot of one year of Hersh's life as an 18-year-old, based on the diary she kept at the time.
She says in the foreword that "this wasn't a year when a lot happened, in my opinion". Well, not much apart from living in a squat, having a breakdown, being wrongly diagnosed with schizophrenia, then correctly with bipolar disorder, moving to Boston, landing a record contract and making her band's first album... and having her first baby.
"I had thought this was a dark year which I never wanted to return to, a year to be ashamed of," she admits, munching on a digestive biscuit in a London hotel. "But to write this I had to return to that period in my mind, and I realised that it was actually quite a lovely, sweet time. I wanted to capture the light as well as the dark. As a band and friends we were goofballs, puppy dogs. Being diagnosed bipolar, I was worried that we wouldn't have shared perceptions, but in fact all the people in the book who have read it have said: 'Yes, that was what it was like'."
It takes hearing Hersh reading excerpts from the book - which she does later that night at the Bloomsbury Theatre, as well as play songs from the time - to understand fully the inherent humour in what's often a difficult book. Tellingly, she explains to the audience that she's going to leave out the bits where her delirium and hallucinations put her in hospital because she doesn't like reading them "and you probably won't want to hear them".
Still, such difficult chapters do give us an incredible insight into her remarkably conflicted mind, and how that expressed itself in song. The unique way in which she writes frightens her but is also the source of her creativity: Hersh still believes, to this day, that she doesn't invent her songs, but they come to her.
"It's a curse, but I worship what comes out of it," she says. "I think writing the book has helped me understand that I hear ambient noise, and the noises build up. So if there's a whirring fan in a room then the noise of that fan continues in my perception even when I've left the room. Then a car can drive by and the sound of it will keep driving by in my mind. This is the vocabulary that the song needs, and then it forms itself into something cohesive. I'm just listening the whole time."
And yet Hersh insists that her songs - which she admits are "pictures of what I've heard, snatches of conversation... an incorporation of all my senses" - are not autobiographical.
"I know this sounds odd, but the songs are an interpretation which is not fully mine. Sometimes I will come back to a song 10 years later and finally realise what it was talking about. I appreciate that this isn't far off schizophrenia and I understand why I was diagnosed as such - because you're talking about voices in your head that are describing what's going on in your life."
In fact, Hersh has spent her entire career downplaying the autobiographical element to her songs. I ask her whether that made it all the harder to write a memoir.
"I get lots of people saying 'of course, you were 18 then', but I don't think I've changed at all," she smiles. "I make it sound in the book like maybe I've worked things out but I still run away, I'm still bipolar, I still struggle with the music industry, I still get haunted by songs.
"The difference between a book and a song is that when you write a really good song, it's beneath your personality in a way. That's why songs resonate with other people, because you're not presenting yourself, you're presenting us as a people. But yes, this book is me, which makes it harder for me to believe that it was a good idea to publish it."
Not for the first time, her blue eyes sparkle and she laughs. On the very first page she admits that she's not the kind of person who writes books and she doesn't read them either, because she "can't sit still in the same place for long enough".
So why did she write Paradoxical Undressing? The answer is typical, contrary Hersh - she was approached to have a memoir ghostwritten, agreed, and then hated "months of sitting around talking about my feelings". But unfortunately management noticed that there wasn't a book and told her that she had to write it. It took her four years. But the results are startlingly original and truly moving.
"Basically, once I started it, it had to be good," she says. "I didn't want to sound 40 when I was supposed to be 18, and I wanted to try and work towards having a kind of melody and rhythm in the prose, too. I had to learn how to write without being clever or stupid, and once it found its own voice, I realised that the book had something that everybody wants: a little bit of peace. You can't control the maelstrom but you can control the peace you inject into it. And that's the only reason I published it really, for people like me who might also want a little bit of peace."
Paradoxical Undressing (Atlantic) is out now. Download songs in the book from www.kristinhersh.com.